ALBERT

Beschreibung: Esterification of fatty acids with glycerol is characterized by negligible solubility of the two liquid phases. The reactions to mono-, di- and triglycerides taking place in the fatty acid phase, are limited by chemical equilibrium. The scope of this study is to investigate in a tubular reactor the conversion of a homogeneous mixture of oleic acid and glycerol in tert -butanol. The liquid composition in this study was 1 mol of oleic acid, 6 mol of glycerol and 14 mol of tert -butanol. Experiments were conducted in a tubular reactor at 35 atm over a temperature range of 200–240 °C and residence times of 0.7–17.6 h to determine the kinetics and the chemical equilibrium. The selectivity to monoolein was 〉95 mol %. A reversible second order reaction fits the data well.

Beschreibung: Commercially available refined vegetable oils were investigated as calibration standards for the filtration device and protocol specified by ASTM D7501 for conducting the biodiesel cold soak filtration test. Filtration time was determined to be a function of the amount of vacuum applied during filtration, with an 8 % change in the filtration time of soybean oil occurring across the vacuum range specified by ASTM D7501. At a constant vacuum of 57 cm Hg the mean filtration time of 150 mL of soybean oil was independent of operator, device, and oil lot number. Mean filtration time was also largely independent of brand: the average of the mean filtration times of replicate samples of seven brands of soybean oil was 396 s with a minimum significant difference (MSD) of 28 s, and the filtration times of seven of eight brands of soybean oil tested fell within this MSD. Refined edible-grade corn, canola, peanut, safflower and sunflower oils gave reliable filtration times and would be suitable standards. Each oil exhibited a characteristic filtration time, all greater than that for soy oil. Filtration times were an approximately linear function of kinematic viscosities, as predicted by Darcy’s Law. Edible vegetable oils can serve as reliable, affordable, consistent and generally available materials for confirming the operability of the filtration device used in the biodiesel cold soak filtration test.

Beschreibung: Uniform suspension of particulates (salt or spices) in oil-based marinades requires a gel behavior of the matrix. This can be achieved by adding a solid fat to the liquid oil. Besides rheology, appearance and thermal stability are important for the utilization as marinades. The influence of solid fat concentration ( c fat  = 2.5–5.5 wt%) and average cooling speed (1.4, 2.6, and 4.7 °C/min) on the functional properties of oil-fat gels from palm fat and canola oil was investigated. Oil-fat mixtures showed complex physiochemical behavior depending on the solid fat concentration and cooling rate. All samples had a shear-thinning behavior. Yield stresses and apparent viscosities increased at a constant cooling rate with increasing solid fat concentration. Frequency dependence of storage and loss modulus showed a transition from a viscous solution to a weak gel at c fat 〉 3.5 wt%. Samples at increasing cooling rates transitioned to weak gels at lower fat concentration (2.5 wt%). Mixtures became turbid and increasingly whiter as both solid fat concentration and cooling rates increased, which was explained by increased light-scattering by fat crystal aggregates. Results show the critical importance of proper formulation and preparation conditions on the functionality of oil-based marinades.

Beschreibung: Natural antioxidants to inhibit oxidation in edible oils are in high demand. Grape pomace is an abundant, inexpensive source of polyphenolic antioxidants, which are responsible for numerous health benefits. We examined pomace from eight varieties of Midwestern hybrid grapes for phenolic content and antioxidant activity. Ethanolic extracts produced from the pomace of each grape variety were added to two model systems, bulk soybean oil and oil-in-water emulsions, to determine antioxidant activity. Oxidation was monitored in each model system at a temperature appropriate to that particular system. While the extracts had relatively little effect in bulk oil, we observed dose-dependent antioxidant effects of some extracts in oil-in-water emulsions. Oxidation in bulk oils was assessed via total polar compounds and polymerized triacylglycerols. Oxidation in emulsions was assessed by peroxide value, headspace oxygen measurements, gas chromatography of headspace volatiles, and fatty acid analysis. Pomace extracts derived from red grapes generally outperformed those from white grapes, with the Marechal Foch variety showing high antioxidant activity at intermediate concentrations. At higher concentrations, Marechal Foch, Corot Noir, Frontenac, and Norton extracts showed promising antioxidant activity. This is the first report on antioxidant activity in an oil and emulsion setting for many of these grape varieties.

Beschreibung: There is a need to verify the quality of organically produced olive oils and to compare them to conventional ones. The objective of this study was to assess possible differences in nutritional quality between agronomic practices in Picual and Hojiblanca olive oil varieties at different stages of olive ripeness. The results showed that organic versus conventional cultivation did not consistently affect acidity, peroxide index or spectrophotometric constants of the virgin olive oils considered in this study. On the contrary, phenol content, oxidative stability, tocopherol content and fatty acid composition were affected by the agronomical practices. Principal component analysis indicated that linolenic acid and β-tocopherol were mainly responsible for discriminating Hojiblanca organic oils, whereas total phenols, palmitoleic acid and α-tocopherol were the major contributors to differentiating Picual conventional oils. Lignoceric and stearic acids were related to oils from unripe and ripe olive fruits, respectively. Long-term experiments are required to confirm these results.

Beschreibung: The aim of this study was to classify Turkish commercial extra virgin olive oil (EVOO) samples according to geographical origins by using surface acoustic wave sensing electronic nose (zNose™) and machine vision system (MVS) analyses in combination with chemometric approaches. EVOO samples obtained from north and south Aegean region were used in the study. The data analyses were performed with principal component analysis class models, partial least squares-discriminant analysis (PLS-DA) and hierarchical cluster analysis (HCA). Based on the zNose™ analysis, it was found that EVOO aroma profiles could be discriminated successfully according to geographical origin of the samples with the aid of the PLS-DA method. Color analysis was conducted as an additional sensory quality parameter that is preferred by the consumers. The results of HCA and PLS-DA methods demonstrated that color measurement alone was not an effective discriminative factor for classification of EVOO. However, PLS-DA and HCA methods provided clear differentiation among the EVOO samples in terms of electronic nose and color measurements. This study is significant from the point of evaluating the potential of zNose™ in combination with MVS as a rapid method for the classification of geographically different EVOO produced in industry.

Beschreibung: Linoleate 13-lipoxygenase from Burkholderia thailandensis was expressed in Escherichia coli for the production of 13-hydroxyoctadecadienoic acid (13-HODE), an antiseptic emulsifier. Linoleate 13-lipoxygenase in cells had higher thermal stability than the purified enzyme. To increase 13-HODE production, recombinant cells were permeabilized by solvents, detergents, salts, and other chemicals. The enzymatic activity in cells was the highest for permeabilized cells treated with 0.5 M NaCl among the permeabilizers tested. The optimal reaction conditions for the production of 13-HODE from linoleic acid by permeabilized cells treated with 0.5 M NaCl were at pH 7.5, 25 °C, 20 g/l linoleic acid, 15 g/l cells, 0.15 mM Cu 2+ , and 6 % (v/v) methanol in a 100-ml baffled flask containing a 5-ml working volume with agitation at 200 rpm. Under these conditions, permeabilized cells produced 15.8 g/l 13-HODE after 30 min with a conversion yield of 79 % (w/w) and a productivity of 31.6 g/l/h. The conversion yield and productivity of permeabilized cells for 13-HODE production were higher than those of purified and crude enzymes as well as nonpermeabilized cells. Therefore, permeabilized cells were efficient biocatalysts for 13-HODE production. To the best of our knowledge, this is the first report of the production of 13-HODE using cells.

Beschreibung: Gamma (γ-T3) and delta (δ-T3) tocotrienols are the most potent natural protective agents against harmful effects of radiation exposure and there is substantial interest in advancing these tocols toward Food and Drug Administration approval. However, co-administration with alpha tocopherol is reported to interfere with the radioprotective properties of the tocotrienols. The objective of this study was to test various flash chromatography conditions for the purification of fractions with a high proportion of γ-T3 or δ-T3 and a minimal amount of alpha isomers from tocol extract obtained from rice bran oil deodorizer distillate (RBODD). Load size (0.125, 0.250, 0.500 and 1.000 g), sample cartridge type (pre-packed silica cartridge, empty cartridge+Celite 545) and mobile phase gradient [varying proportions of hexane–acetic acid (99.1:0.9 v/v) and ethyl acetate–acetic acid (99.1:0.9 v/v)] were evaluated. Peak resolution was best with a load size of ~1 % column capacity and a 5-g silica sample cartridge coupled with a 12-g silica column. A linear gradient of 0.8 % ethyl acetate–acetic acid (99.1:0.9 v/v) to hexane–acetic acid (99.1:0.9 v/v) (50 min )  → 100 % ethyl acetate–acetic acid (99.1:0.9 v/v) (5 min) resulted in the best separation of tocols. The method developed was used to isolate tocols from samples of crude RBODD, tocol concentrate and tocol-rich extract. The use of these conditions with a tocol-rich extract resulted in several fractions containing 100 % purities of both γ-T3 and δ-T3.

Beschreibung: Oil and phenolics were extracted from Descurainia sophia (Sophia) seeds by a supercritical CO 2 system. Extractions were conducted in two sequential steps, first using 100 % CO 2 and then adding 10 % ethanol as co-solvent. The extracts were collected in each step using two separate collectors operating at different pressures. The extraction run was 3 and 4 h for the first period, and 2 h for the second period. The majority of the oil was collected in the first extraction period while phenolic compounds were obtained in the second extraction period. A combined mode of static/dynamic extraction (3 h running and 1 h soaking in CO 2 ) was also used in the first extraction period, which enhanced the total extraction yield (29.3 ± 0.5 %) and was comparable to the 4 h extraction yield (31.4 ± 0.1 %). The total fatty acid (FA) content of oil in collector 1 (0.94 g) was nearly twice that in collector 2 (0.60 g). The oil contained 14 FAs with α-linolenic being predominant (48.5 %), with a total 91.1 % unsaturated FAs, a ω3/ω6 ratio of 2.7, and an erucic acid content of 6.2 %. More than 10 phenolic compounds were detected by HPLC in the Sophia seed extracts of which sinapic acid was the dominant compound. Sophia seed extracts showed high levels of antioxidant activity. These results suggest that Sophia seed oil and phenolics have the potential for functional food and pharmaceutical applications.

Beschreibung: In this study, the Ayvalik olive variety, an important and widely grown olive variety in Turkey, was chosen. A month prior to blooming and 2 months prior to harvesting in 2011 and 2012, three different concentrations of boron (100, 150 and 250 ppm) were applied to the olive leaves with or without boron deficiencies. After the application, quality criteria, fatty acid composition, total phenol contents and major volatile compounds of olive oil that was obtained from the harvested olives were investigated. Boron application to the olive trees with boron deficiencies has improved both the amount and the olive oil quality. Experimental results show the significance of boron for olive farming. Application of boron in 150 ppm led to a better olive oil quality by improving fatty acid composition [oleic acid (76.03 %), linoleic acid (9.68 %), linolenic acid (0.56 %), monounsaturated fatty acid (77.24 %)], total phenol content (422.94 ppm) and major volatile compounds [ E -2-hexenal (43.12 ppm), hexanal (3.02 ppm), Z -3-hexenol (1.13 ppm)] in both harvest seasons (2011–2012) and in both olive orchards with or without boron deficiencies.

Beschreibung: A simple setup using a 365-nm light-emitting diode coupled to a USB spectrometer through an optical fiber, in a front-face fluorescence configuration, was used to investigate the heat-induced deterioration of virgin olive oil at different heating temperatures and times. The samples were heated for 30, 60, 120 and 180 min for every temperature setting of 140, 160 and 180 °C, respectively. Two important results are reported in this article. First, a neo-formed compound around 665 nm due to the degradation of chlorophyll was observed. This new peak was attributed to pyropheophytins. The second result showed an important rise of the peak around 489 nm, which corresponded to the oxidation products. The correlation obtained between the peroxide value and the 489 nm peak using principal component analysis revealed the mechanism of the oxidation process. It further showed that the peak around 489 nm is a direct consequence of the degradation of hydroperoxide.

Beschreibung: Brønsted–Lewis acidic ionic liquids (IL) were used in the esterification of glycerol and acetic acid to produce glycerol triacetate. The results show that the IL (3–sulfonic acid)–propyltriethylammonium chloroironinate [HO 3 S–(CH 2 ) 3 –NEt 3 ]Cl–[FeCl 3 ] x (molar fraction of FeCl 3 , x  = 0.67) was an efficient catalyst for the esterification reaction. The yield of glycerol triacetate and its content were greater than 98 % when reacted under reflux for 4 h. It was observed that a synergistic effect of Brønsted and Lewis acid sites enhanced the catalytic performance of IL. The reusability of IL was good. After six reaction cycles, the glycerol triacetate yield and concentration were still greater than 98 %. Likewise, the Brønsted–Lewis acidic IL was an efficient catalyst for esterification reactions of high boiling points alcohols with acetic acid.

Beschreibung: The epoxy ring opening and vicinal diacylation of fatty acids in vegetable oils was found to be promising reaction to synthesize stable biolubricants and bioplasticizers. The current research investigation is emphasized on the synthesis of a value added product vicinally diacylated canola oil by sulfated-ZrO 2 . The two-step research approach employed includes: (i) epoxidation, and (ii) epoxy ring opening and vicinal diacylation of epoxidized triglycerides in the canola oil. Sulfated-ZrO 2 was prepared and characterized to measure the physico-chemical properties required for the effective catalysis. The Taguchi (L16 orthogonal array) statistical design method was employed to optimize the process conditions for the maximum formation of diacylated canola oil. Sulfated-ZrO 2 demonstrated promising activity for the epoxy ring opening and vicinal diacylation of canola oil, and 99 % conversion was achieved at the optimum process conditions of temperature 130 °C, epoxy to acetic anhydride molar ratio (1:1.25), 16 wt% of catalyst loading and reaction time of 1 h which were inferred from the Taguchi analyses. The products were characterized and confirmed with FT-IR, 1 H NMR and sodium spray mass spectroscopy. Spectroscopic analysis also confirmed the absence of intermediate products. The statistical analyses was undertaken to determine the order, rank and interactions among the process variables. The reaction followed Langmuir–Hinshelwood–Hougen–Watson type mechanism and the kinetic data was fitted in overall second order equation. Calculated apparent activation energy was 23.1 kcal/mol.

Beschreibung: The aim of the study was to determine the effect of oil degradation on the content of glycidyl esters (GEs) in oils used for the frying of French fries. As frying media, refined oils such as rapeseed, palm, palm olein and blend were used. French fries were fried for 40 h in oils heated to 180 °C in 30-min cycles. After every 8 h of frying, fresh oil and samples were analyzed for acid and anisidine values, color, refractive index, fatty acid composition, and content and composition of the polar fraction. GEs were determined by LC–MS. Hydrolysis and polymerization occurred most intensively in palm olein, while oxidation was reported for rapeseed oil. The degradation of oil caused increased changes in the RI of frying oils. Losses of mono- and polyunsaturated fatty acids were observed in all samples, with the largest share in blend. The highest content of GE found in fresh oil was in palm olein (25 mg kg −1 ) and the lowest content of GE was found in rapeseed oil (0.8 mg kg −1 ). The palm oil, palm olein and blend were dominated by GEs of palmitic and oleic acids, while rapeseed oil was dominated by GE of oleic acid. With increasing frying time, the content of GEs decreased with losses from 47 % in rapeseed oil to 78 % in palm oil after finishing frying.

Beschreibung: Molecular compound formation between multicomponent triacylglyceride (TAG) mixtures was characterized using palm oil mid fraction enriched in sn -1,3-dipalmitoyl-2-oleoylglycerol (cPOP) and a commercial fraction enriched in sn -1,3-dioleyl-2-palmitoylglycerol containing a wide range of TAGs (cOPO). Compound formation occurred at a 1:1 (w/w) ratio of cPOP to cOPO corresponding to an equal parts ratio of two different families of TAGs. One family of TAGs consisted of a grouping of all TAGs composed of a saturated–oleic–saturated (StUSt) positioning of fatty acids. The second family consisted of a grouping of all TAGs composed of all oleic–saturated–oleic and saturated–saturated–oleic fatty acids (UStU, StStU). An increase in solid fat content, peak melting temperature, and crystalline domain size and a change in crystalline microstructure were observed at this ratio corresponding to an overall equality in the amount of cPOP to cOPO. This indicates that it is possible to achieve that same level of solid fat content and hardness as a mixture containing more saturates, simply by slightly decreasing the saturates and substituting an oleic monounsaturated fatty acid containing TAG mixture such that a molecular compound is formed. The increase in full-width at half-maximum indicated a decrease in crystalline order and/or decrease in crystal domain size. The characteristic spherulitic crystalline microstructure of OPO changed to small granular crystals upon addition of cPOP. This discovery may allow for the incorporation of a larger proportion of healthy monounsaturated fats into foods while decreasing the use of saturated and trans fats.

Beschreibung: The international standard method for the determination of trypsin inhibitor activity (TIA) in soya products, ISO 14902, was compared with the American Association of Cereal Chemists’ standard AACC 22-40.01 as modified by Hamerstrand in 1981 (AACC-based method), using soybean meals as matrices. TIA, expressed as milligram of inhibited trypsin per gram of sample, was determined by both methods in each of 30 samples of soybean meal. TIA values according to ISO 14902 were significantly lower ( P  〈 0.001) than those afforded by the AACC-based method. This difference, which means that AACC-based method and ISO 14902 TIA values are not directly comparable, is attributable to between methods differences, in decreasing order of influence: particle size ( P  〈 0.01), trypsin inhibitor extraction method ( P  〈 0.05), and trypsin substrate ( P  〈 0.01). N -benzoyl- l -arginine-4-nitroanilide hydrochloride, the ISO 14902 trypsin substrate, affords TIA values 6.4 % higher than the racemic mixture used by the AACC method, but it seems unlikely that in most contexts this advantage would outweigh the disadvantage of its greater cost.

Beschreibung: Changes in the composition of soybean oil during deep-fat frying with wheat dough (WD) and chicken breast meat (CBM) were comparatively investigated using gas chromatography–mass spectrometry and Fourier transform infrared spectroscopy (FTIR). The amounts of saturated fatty acids (FAs) and short-chain FAs were increased. The amount of unsaturated FAs was decreased as the processing time increased. An increase in the amount of tetradecanoic acid and 9- cis -hexadecanoic acid was observed during the CBM frying only. The FTIR spectrum of frying oil was analyzed by extracting the entire information as the area ratios based on vibration absorptions of the specific functional groups. Changes in content of functional groups, namely cis C=C, trans C=C, C=O, C–O, O–H, and C–H, were studied by the FTIR-based method. Based on the changes in the content of FAs and functional groups, soybean oil fried with CBM degraded more quickly than that fried with WD. Moreover, good linear correlations between the change in contents of functional groups and the mass percentages of FAs were also observed. The FTIR-based method could be used in real time to monitor the quality of frying oil during the deep-fat frying.

Beschreibung: NMR spectroscopy was used to distinguish pure sunflower lecithin from that blended with soy species, and to quantify the degree of such adulteration. Sample preparation included liquid extraction of lecithin blends and measurement of polar and non-polar fractions using 31 P and 1 H NMR spectrometry. Several phospholipid species, linolenic acid and stachyose were found to be characteristic for sunflower lecithin authentication. For quantitative analysis, partial least squares regression (PLS) was utilized for modeling NMR data of authentic lecithin samples and in-house prepared blends ( n  = 80). The models based on phospholipid, fatty acid and saccharide distributions were validated using independent test sets. PLS based on saccharide composition is able to estimate lecithin falsification regarding its vegetable origin with the sensitivity and root mean square error of validation below 1 % w/w and 3.5 % w/w, respectively. Prediction error was improved by modeling the whole lecithin profile (phospholipids, fatty acids, and saccharides). Repeatability and precision expressed in coefficients of variations was estimated to be below 8 %. The developed approach allowed the evaluation of the composition of lecithin blends of unknown soy and sunflower content on the basis of multiple chemical components.

Beschreibung: This work was to correlate physical properties with adhesion properties of soy protein-based adhesives. By building such a correlation, the adhesion properties can be predicted by measuring physical properties of soy protein-based adhesives. In this context, three important physical properties, viscosity, tacky force, and water resistance, were selected to correlate with adhesion strength of enzymatically modified soy protein-based adhesives (ESP). Response surface methodology, specifically central composite design, was used with three independent variables to prepare ESP: trypsin concentration ( X 1 ), incubation time ( X 2 ), and glutaraldehyde (GA) concentration ( X 3 ). The three physical properties measured were all greatly affected by our three independent variables with significance at the 95 % confidence level. The responses were then correlated with the adhesion properties of ESP. In conclusion, viscosity can be used to predict the dry adhesion strength of ESP based on the coefficient of determination ( R 2 ) of 0.8558. In addition, tacky force and water resistance can be used to represent wet adhesion strength of ESP based on R 2 of 0.7082 and 0.6930, respectively ( P  〈 0.05). This work preliminarily identified the significant physical properties that can predict the adhesion strength of the ESP system crosslinked with GA, but the results need to be further confirmed by another protein modification system to give a generic conclusion.

Beschreibung: This study investigated the influence of water content in combination with selected minor components including oleic acid, stigmasterol, α-tocopherol, and Trolox on their association colloid formation as well as their impact on lipid oxidation in bulk corn oil. First, surface activity of each minor component was evaluated by determining the ability of these components to lower the interfacial tension between bulk oil and water. All components but α-tocopherol were able to decrease interfacial tension of stripped oil. Second, the critical micelle concentration (CMC) of each minor component was determined in bulk oil with no water added and in the presence of 1000 ppm of water. In the bulk oil without extraneous water, we could not determine the CMC of minor components in the range of concentrations studied. However, in the presence of 1000 ppm of water, only stigmasterol could form association colloids at the CMC of 20 mmol/kg oil. Last, the effect of water content (400 and 1000 ppm) and minor components on lipid oxidation in bulk oil was studied by following the lipid hydroperoxides and hexanal formation during storage at 55 °C. Different water content did not significantly impact the lag time of lipid oxidation compared with the control. Interestingly, water caused prooxidant by decreasing the lag time of lipid hydroperoxides and hexanal formation in bulk oil containing oleic acid, stigmasterol, and Trolox compared with the control of each system. On the other hand, there was not significant impact of water on the antioxidant activity of α-tocopherol, a lipid soluble antioxidant in bulk oil. This study highlights the impact of water content on the surface activity of minor components as well as on the oxidative stability in bulk oil.

Beschreibung: Emulsifiers and stabilizers play an important role in emulsion stability. Optical characterization and droplet size distribution of oil-in-water emulsions formulated with different types and concentrations of modified sunflower lecithin [phosphatidylcholine (PC) enriched lecithin and deoiled sunflower lecithin], with or without chia mucilage (0.75 % wt/wt), have been evaluated as a function of storage time at 4 ± 1 °C. Emulsions with PC-enriched lecithin (without chia mucilage) exhibited the highest stability at the different concentrations because of the high PC/phosphatidylethanolamine ratio in comparison to Control lecithin. The addition of 0.75 % wt/wt mucilage contributed to obtain stable emulsions for all type and concentrations of emulsifiers studied, mainly with PC-enriched lecithin due to the reduction of the mobility of oil particles by the formation of a tridimensional network.

Beschreibung: The flow behavior and viscosity of TAGs containing oleic and stearic acids were examined in the liquid phase as well as at temperatures close to the onset of crystallization by means of a temperature-controlled rheometer. Gelling and crystallization transitions were unambiguously identified by singularities in the viscosity versus temperature curves of the TAGs. An additional transition between the gelling and onset of crystallization temperatures, attributed to the reorganization of the gel, was observed in the symmetrical TAGs only. The effect of the cooling rate, ranging between 0.1 and 5 °C/min, was investigated. The flow behavior of the studied TAGs was shown to be strongly determined by structural parameters (symmetry, degree of unsaturation). The flow behavior was also affected significantly by the cooling rate, suggesting that to certain extents the flow behavior determined by structural parameters could be changed by manipulating the cooling rate. The study confirmed that TAG crystallization is initiated by and depends, at least in part, on complex molecular short range order transformations occurring in the melt. The findings of the study may be valuable for evaluating systems and equipment that are involved in the storage, handling and processing of materials incorporating these TAGs.

Beschreibung: The autoxidation of purified triacylglycerols obtained from fish, canola, and olive oils in the presence of different concentrations of hydroxytyrosol at 60–100 °C was evaluated by different kinetic parameters including the stabilizing factor ( F ) as a measure of effectiveness, the oxidation rate ratio (ORR) as a measure strength, and the antioxidant activity ( A ) which combines the F and ORR parameters. The overall performance of hydroxytyrosol was attributed to the main reaction of chain termination ( \( {\text{ROO}}{\cdot} + {\text{ InH }} \to {\text{ROOH }} + {\text{ In}}{\cdot} \) ) as competed with the main oxidation reaction of chain propagation ( \( {\text{ROO}}{\cdot} + {\text{ RH}} \to {\text{ROOH }} + \, R{\cdot} \) ) and, additionally, the antioxidative side reactions of chain propagation ( \( {\text{In}}{\cdot} + {\text{ ROO}}{\cdot} \to {\text{In}} - {\text{OOR}} \) and \( {\text{In}}{\cdot} + {\text{ In}}{\cdot} \to {\text{products}} \) ), and the pro-oxidative side reaction of chain initiation ( \( {\text{InH }} + {\text{ ROOH}} \to {\text{In}}{\cdot} + {\text{ RO}}{\cdot} + {\text{ H}}_{ 2} {\text{O}} \) ) in some cases.

Beschreibung: Since the nutritional value of farm-raised fish fillets is directly related to the diet provided, we supplemented the diet of Tilapia ( Oreochromis niloticus ) with a blend of chia ( Salvia hispanica L.) oil, tung ( Aleurites fordii ) oil, and conjugated linoleic acid (CLA) to evaluate the effects on the fatty acid composition. Vitamin E was also added to the diet to improve the antioxidant capacity of tilapia fillets. We observed an increase in α-linolenic acid content (from 6.56 to 19.03 mg g −1 of total lipids), as well as the incorporation of CLA and conjugated linolenic acid (CLnA) isomers in the fillets. The addition of vitamin E resulted in the antioxidant capacity improvement of the fillets and higher values were found after 15 feeding days (39.25 µmol TE g −1 in the Ferric Reducing Ability Power assay). Supplementation proved to be an excellent tool to improve the nutritional value of fish fillets.

Beschreibung: The supercritical CO 2 fluid extraction process was used to obtain seed oils. The compositional analyses of the seed oils of Amorpha fruticosa L., Caragana microphylla Lam and Elaeagnus angustifolia L. were performed by GC–MS, from which 18–22 fatty acid compositions were identified, and their main components were linoleic acid (49.10–66.39 %) and oleic acid (11.95–41.10 %). The seed oils were rich in unsaturated fatty acids, which accounted for 79.75–91.19 %. The in vitro anti-oxidant activities of the seed oils were measured by the DPPH, ABTS and phosphomolybdenum complex assays. The IC 50 s of the seed oils were 6.5110–12.6599 mg/mL tested by DPPH assay, and the IC 50 s were in the range of 0.6872–1.9310 mg/mL tested by ABTS assay. The anti-oxidant activities of seed oils decreased in the order of A. fruticosa  〉  C. microphylla  〉  E. angustifolia (A) 〉  E. angustifolia (D). In vitro antimicrobial activities of seed oils against five bacteria were tested by microdilution method. The MIC values of the oils against Bacillus subtilis , E. coli , S. aureus , P. solanacearum and B. thuringiensis were in the range of 26–36, 30–38, 58, 56–58 and 56–58 mg/mL, respectively, while the MBC values were in the range of 30–40, 34–42, 58, 56–58 and 58 mg/mL, respectively. In vitro antifungal properties of the seed oils against four plant pathogenic fungi were tested by the mycelial growth rate method. The EC 50 s of seed oils against V. mali , C. gloeosporioides , F. graminearum and B. cinerea were in the range of 17.51–19.25, 15.58–19.12, 8.00–17.12 and 18.76–19.14 mg/mL, respectively. The seed oils showed moderate anti-oxidant and antimicrobial activities.

Beschreibung: Lipases from Geotrichum candidum were produced in two different medium: A = 12 % (w/v) clarified corn steep liquor (CCSL) + 0.6 % (w/v) soybean oil (SO) and B = 3.5 % (w/v) yeast hydrolysate (YH) + 0.7 % (w/v) SO. Lipases were partially purified from both media by hydrophobic interaction chromatography using 3.0 mol L −1 of NaCl as mobile phase, and they were characterized in the crude and partially purified forms. The recovery of lipase activity from CCSL and YH via HIC were 96 and 94.3 %, and the purification factors were 44.3 and 86.7-fold, respectively. All evaluated lipases had similar optimum pH (7.0–7.7), but, for the CCSL crude lipase, optimum temperature (47 °C) was 10 °C higher than others lipases evaluated. CCSL crude lipase possessed a higher thermo stability than YH crude lipase, e.g., at 37 °C (pH 7.0) the half-life of CCSL crude lipase was 19.25 h and at pH 8.0 (30 °C) the half-life was 48 h, which are five and ten times higher than with YH crude lipase, respectively. On the other hand, the YH crude lipase possessed a higher catalytic constant ( k cat  = 2.3 min −1 ) but with almost the same catalytic efficiency ( K m / k cat  = 32.12 mg mL min −1 ) in relation to CCSL crude lipase. The lipases differ in biocatalytic properties between substrates, suggesting that the two lipases can be employed for different applications.

Beschreibung: In this study, we investigated the effect of monoacylglycerol (MAG) as a structuring agent on the physicochemical, microstructure and rheological properties of chicken fat. The fatty acid composition, oxidative stability, free fatty acids (FFA), slip melting point (SMP), solid fat content (SFC), kinetics of crystallization, microstructure and rheological properties of the samples were evaluated. The addition of MAG at a 0.5 % level did not affect the fatty acid composition, induction period of oxidation at 110 °C (IP ox110 ), SFC curve or rheological properties of chicken fat ( p  〉 0.05). However, structured samples containing 3.0 and 5.0 % MAG had higher saturated fatty acid (SFA) content, SFC, SMP, FFA content and IP ox110 ( p  〈 0.05). The addition of MAG led to a reduction in the IP of oxidation at 60 °C (IP ox60 ) and increased the oxidation rate of fats, as measured by the Schaal oven test. Samples containing 3–5 % MAG had higher SFC content, higher loss, storage and complex moduli, higher complex viscosity, and a lower induction period of crystallization (IP cryst ) and tan δ than chicken fat. Investigations by polarized light microscopy confirmed the presence of increased crystal content in samples containing higher MAG levels. These results show that structured chicken fats have the potential for application in the production of soft tub margarine and Iranian vanaspati.

Beschreibung: The phasing out of the use of urea–formaldehyde adhesive in the fabrication of interior-used hardwood plywood requires development of environmentally friendly bio-based wood adhesives. We recently reported that phosphorylation of soy flour (SF) using phosphoryl chloride (POCl 3 ) greatly improved the moisture resistance of soy flour adhesive. In the present study, we investigated the effects of inorganic oxidizing agents, such as NaClO 2 and Ca(NO 2 ) 2 , to further improve the wet bonding strength of phosphorylated SF (PSF) wood adhesive. We report that addition of 1.8 % (wet weight basis) Ca(NO 2 ) 2 to phosphorylated SF (PSF) adhesive formulation containing 25 % soy flour solids increased the wet bonding strength to greater than 3 MPa at 140 °C hot-press temperature. The water resistance testing of the glued three-ply hardwood plywood panels passed the three-cycle soak/dry test recommended by the American National Standard for Hardwood and Decorative Plywood/Hardwood Plywood and Veneer Association protocol (ANSI/HPVA HP-1-2004). Since the process involves only inorganic chemistry and no petroleum-based chemicals such as formaldehyde or polyamidoamine–epichlorohydrin are used, the PSF + Ca(NO 2 ) 2 adhesive is non-toxic and environmentally safe.

Beschreibung: Extruded cereal snacks are usually deficient in protein, mineral ingredients, valuable fatty acids. With the rise of health awareness among consumers, food manufacturers and scientists are pressed to take measures in order to develop new functional/health-beneficial foods. The aim of this work was to manufacture extruded crisps enriched with α-linolenic acid (obtained from linseed oil) and to observe whether storage of the product for the period of 6 months would cause its disqualification, primarily due to its sensory properties and secondarily due to its chemical properties. The research demonstrated that the addition of linseed oil to corn crisps at the amount of 5 % enables to obtain functional corn crisps containing over 2 g of ALA in a portion of 100 g even after 6 months of storage at room temperature. ALA-enriched crisps maintain the original sensory profile after 6 months of storage and their sensory profile is similar to the profile of crisps without the addition of linseed oil if they are packed in barrier packaging filled 100 % with argon. Therefore, they may be a healthier alternative to typical corn crisps.

Beschreibung: Fat plays an important role in caramel quality attributes, yet there is very little published work on how fat type and level influence caramel characteristics. Fat content was increased from 0 to 20 % to determine the effects of total fat content on caramel texture attributes such as cold flow, hardness, stickiness and tensile strength. Solid fat content (SFC) was also varied, from 3 to 90 %, by using commercially-available fats with varied SFC at 22 °C. Cold flow decreased significantly with increased fat content, with greater effect for fats with higher SFC. Changes in caramel hardness with fat content were dependent on SFC. Hardness generally decreased with increasing fat content for the fats with low SFC, with the 3 % SFC fat softening the most. Hardness increased slightly with fat content for the hardest fat (90 % SFC). Stickiness generally decreased with increasing fat content although the effect was significantly higher with higher SFC fats. These results document that both fat content and SFC significantly influence caramel texture attributes.

Beschreibung: Roasting enhances sensory quality of wild almonds ( Amygdalus scoparia ). The aim of the study was to evaluate the use of microwaves (480 W for 3 or 4 min) in roasting of wild almonds in comparison with traditional Spanish (165 °C for 20 min) and Iranian (soaking in 20 % NaCl in water for 30 min, drying at 60 °C for 2 h and roasting at 135 °C for 20 min) hot-air processes. The influence of roasting wild almonds on moisture and oil contents, crispness, fatty acid profile, volatile compounds, and odour intensity was investigated. Roasting causes changes in appearance, texture and flavour, due to dehydration, browning, lipid oxidation, and diverse structural changes. The moisture content and hardness of the samples significantly decreased with all roasting methods. Roasting resulted in higher amounts of characteristics aroma compounds and only microwave roasting increased the oil content. The final recommendation is that microwave roasting at 480 W for 4 min led to roasted almonds of high physicochemical [dark and intense colour ( L *44.9, a *8.4, and b *19.6), the highest content of total volatile compounds (132 mg kg −1 ), 85.2 % of unsaturated fatty acids], and sensory (high intensity of “roasted almond” aroma) quality. Microwaves can be used for roasting wild almond as a quick, safe, and economical method.

Beschreibung: Viscosity is an important physical property of fatty acid methyl esters (FAME) and biodiesel (mixture of FAMEs). In this work, quantitative structure–property relationship (QSPR) for estimation of dynamic viscosity of FAMEs and biodiesel is approached via the Gibbs energy additivity method. The Gibbs energy of dynamic viscous flow is simply derived from the sum of the Gibbs energy of kinematic viscous flow and Gibbs energy of volumetric expansion. The derived model can be used for estimation of dynamic viscosity of saturated and unsaturated FAMEs commonly found in nature. Also, the proposed model can be extended to a mixture of FAMEs or biodiesel as well as biodiesel blends. Thus, the dynamic viscosity of FAMEs as well as neat and blended biodiesels can be estimated by the same equation from the carbon number ( z ) and number of double bonds ( n d ) at different temperature ( T ). The average absolute deviation (AAD) values for saturated, unsaturated FAMEs, biodiesels, and biodiesel blends (at 20–100 °C) are approximately the same as the original model for estimation of kinematic viscosity.

Beschreibung: The aim of the present work was to investigate the influence of fruit ripening on oil quality and volatile compounds in an attempt to establish an optimum harvesting time for Oueslati olives, the minor olive variety cultivated in Tunisia. Our results showed that many analytical parameters, i.e., peroxide value, UV absorbance at 232–270 nm, chlorophyll pigments, carotenoids and oleic acid contents decreased during ripening, whilst linolenic acid increased. Free acidity remained practically stable with a very slight rise at the highest maturity index. The volatile compounds emitted by the Oueslati olive oil were characterized and quantified by HS-SPME-GC-EIMS. Twenty-three volatile compounds were identified, mainly aldehydes, sesquiterpenes and esters. The results show variations in the volatile fractions and quality parameters of Oueslati extra virgin olive oil obtained at different olive-ripening stages. Fifteen sesquiterpenes were identified for the first time in this cultivar, mainly hydrocarbon derivatives, but also oxygenated ones. On the basis of the quality parameters and volatile fractions studied, the best stage of Oueslati olive fruits for oil processing seems to be at ripeness index about 3.0. Indeed, these results suggested the possibility of using sesquiterpenes for olive authenticity and traceability and demonstrated that the volatile fractions can be used as indicators of the degree of ripening of the olives used to obtain the corresponding virgin olive oils.

Beschreibung: The unsaturated sites in oleic 2-ethylhexyl estolide esters (containing 35 % monoenic fatty acids) were converted into epoxide and five-membered cyclic carbonate groups and the products characterized by Fourier transform infrared spectra (FTIR), 1 H, and 13 C nuclear magnetic resonance (NMR) spectroscopies. Epoxidation of the alkene bonds was accomplished using performic acid generated in situ from formic acid and hydrogen peroxide. Greater than 90 % alkenes were converted into their corresponding epoxide groups as determined by oxirane values and the epoxide ring structure was confirmed by 1 H and 13 C NMR. The estolide ester epoxide material was subsequently reacted with supercritical carbon dioxide in the presence of tetrabutylammonium bromide catalyst to produce the corresponding estolide ester containing the cyclic carbonate group. The signals at 1,807 cm −1 and δ 82 ppm in the FTIR and 13 C-NMR spectra, respectively, confirmed the desired cyclic carbonate was produced. The carbonated estolide ester exhibited a dynamic viscosity, at 25 °C, of 172 mPa·s as compared to 155 mPa·s for the estolide ester starting material. The estolide ester structure of these new derivatives was shown to be consistent throughout their synthesis.

Beschreibung: The lipid content and fatty acid (FA) composition of seeds from the Asian ginseng Panax ginseng growing naturally in taiga forests of the Russian Far East and seeds from cultivated ginseng were studied in this work. The total lipid content of seeds from both wild and cultivated plants was 9–12 % of fresh weight. FA were analyzed as isopropyl esters on a polar capillary column BD-225, which allows good separation of petroselinic and oleic acids. The structure of FAs was confirmed using GC–MS of fatty acid methyl ester (FAME) and 4,4-dimethyloxazoline derivatives. In all the seed samples, the major FA was petroselinic acid 18:1(n-12) which comprised more than 60 %; the contents of oleic and linoleic acids were lower (15–17 and 15–16 %, respectively). Earlier, a higher level (〉80 %) of oleic acid had been reported for ginseng seeds. This discrepancy can be explained by an insufficient separation of these acids on standard columns used for GC of FAME. In general, seeds of wild and cultivated ginseng are very similar in lipid content and FA composition.

Beschreibung: The effects of addition of soy-derived phosphatidylcholine (PC), phosphatidylethanolamine (PE), or phosphatidylinositol (PI) and the contribution of their structural segment during iron-catalyzed autoxidation of canola oil in a water/oil (W/O) (1:1, w/w) emulsion were studied by headspace oxygen consumption using gas chromatography and hydroperoxide production by the ferric thiocyanate method. The phospholipid content was monitored by high performance liquid chromatography. Addition of PC and PE significantly ( p  〈 0.05) improved the oxidative stability of the oil in the emulsion by decelerating headspace oxygen consumption and hydroperoxide production, with the PC having higher antioxidant effect. All phospholipids were degraded during autoxidation of the emulsion, with higher sensitivities of the PE and PC than the PI. Among the structural segments, ethanolamine and phosphoric acid significantly contributed to the antioxidant activity, while inositol showed little effect. Linoleic acid and choline showed the highest antioxidant activity at 350 mg/kg. The results suggest that hydrogen donation and a physical barrier to oxygen contribute to the antioxidant activity of PE and PC in the W/O emulsion, respectively.

Beschreibung: Lauric fat blends (appreciable amount of lauric fat with liquid oil and hard fat) initially formulated for shortening production by grouping triacylglycerol (TAG) melting points were further modified by enzymatic interesterification (EIE) to improve their key functionalities as plastic fats. At a similar fat blend formulation, only the high melting fat and medium melting fat were interesterified in binary-EIE. Meanwhile, both fats and the liquid oil were interesterified in ternary-EIE. The solid fat content (SFC) of all binary-EIE blends was generally retained as similar in the temperature range between 0 and 20 °C when the amount of unsaturated TAGs was limited by excluding the liquid oil during EIE. However, the SFC was significantly reduced at temperatures above 20 °C compared to that of the initial blends. Furthermore, the melting point of binary-EIE blends at BH50H15 formulation prepared with palm stearin and fully hydrogenated rapeseed oil as the hard fat was found to be drastically reduced from 54.6 to 35.3 °C and from 62.8 to 39.2 °C, respectively. In contrast, the SFC of ternary-EIE blends was generally reduced when more unsaturated TAGs were available for EIE by including the liquid oil. However, higher SFC was noticed at temperatures around 10 °C in ternary-EIE blends, as the amount of high-melting fractions in their initial blends was increased from BH50H5 to BH50H15. Eventually, both binary and ternary-EIE were also found to significantly alter the crystal microstructure of lauric fat blends, in terms of crystal morphology, size and network density.

Beschreibung: The composition and physical properties of roll-in shortenings, commonly rich in trans and saturated fatty acids, were investigated and compared to other specialty fats, to provide insights into the physico-chemical origins of their functionality. Triacylglycerols and fatty acid composition, polymorphic and melting behavior, solid fat content and large deformation rheological properties were determined. Roll-in shortenings contained higher amounts of trisaturated and unsaturated triacylglycerols (12–27 %; 47–62 %) than other shortenings (9–11 %; 6–44 %). However, all exhibited high levels of saturates and trans fatty acids and similar crystal characteristics: β′ or mixed β′ and β, irrespective of their end use. Roll-in shortenings had comparable melting peaks (42–52 °C) but sharper melting endotherms with higher enthalpies (38.6–43.3 J/g) than other bakery fats (18.7–25.4 J/g). This was in accordance with their well-defined short spacings, indicative of smaller crystallites with more-ordered packing. Solid fat profiles of roll-in shortenings were akin to all purpose and cake interesterified shortenings, but not to all-purpose and icing shortenings which displayed substantial melting as temperature rises. Differences in large deformation rheology (yield stress: σ * , apparent Young modulus: E app , yield value: C ) were marginal and inconsistent with their solid fat content. Roll-in shortenings exhibited E app , σ and C in the order of 1–2 × 10 6 , 4–7 × 10 4 , and 7–29 × 10 4 Pa, respectively. Particularly, the σ* and C , previously established as major parameters to specify the functionality of roll-in shortenings, were not significantly different ( p  〉 0.05). Overall, roll-in shortening differed from other samples in regard to molecular makeup but not greatly in their physical parameters, suggesting that triacylglycerol composition has important implications on their functionality.

Beschreibung: Frying oils are prone to quality deterioration; because of the high surface area, lipid molecules can interact with air, moisture, and oxidative reagents that promote various reactions. However, the search for effective ingredients for stabilizing frying oil has been slow, given the complexity of the frying processes and lack of effective tools to accurately predict the performance of emerging ingredients. On the other hand, demand for label-friendly food ingredients has increased. This study aimed to develop a rapid method mimicking real frying conditions to allow the screening of a large number of treatments with improved throughput, while evaluating their effectiveness in stabilizing frying oils. The design utilizes multi-well heating blocks of conventional OSI. Repeated frying was conducted using miniature baskets, and validations were conducted to examine the accuracy of the relative efficacy of individual treatments. Utilizing this method as a tool, natural plant extracts, standard antioxidants, and their combinations were evaluated and compared in frying palm oil, which demonstrated that the combination of tocopherols, rosemary extract, and oil-soluble green tea extract was effective for the stabilization of frying oil.

Beschreibung: The oxidation of vegetable oils is generally treated as an apparent first order kinetic reaction. This study investigated the deterioration of crude palm oil (CPO), refined canola oil (RCO) and their blend (CPO:RCO 1:1 w/w) during 20 h of successive deep-fat frying at 170, 180 and 190 °C. Kinetics of changes in oil quality indices, namely, free fatty acid (FFA), peroxide value (PV), anisidine value ( p -AV), total polar compounds (TPC) and color index (CI) were monitored. The results showed that FFA and PV accumulation followed the kinetic first order model, while p -AV, TPC and CI followed the kinetic zero order model. The concentration and deterioration rate constants k , increased with increasing temperatures. This effect of temperature was modeled by the Arrhenius equation. The results showed that PV had the least activation energies E a (kJ/mol) values of 5.4 ± 1 (RCO), 6.6 ± 0.7 (CPO) and 11.4 ± 1 (blend). The highest E a requirement was exhibited by FFA with a range of 31.7 ± 3–76.5 ± 7 kJ/mol for the three oils. The overall E a values showed that the stability of the blend was superior and not just intermediate of CPO and RCO. The correlation of the other oil quality indices with TPC indicated a positive linear correlation. The p -AV displayed the strongest correlation, with mean correlation coefficient r s of 0.998 ± 0.00, 0.994 ± 0.00 and 0.999 ± 0.00 for CPO, RCO and blend, respectively.

Beschreibung: Quercetin shows interesting pharmacological effects, but its use in topical applications is limited by its low skin permeability and solubility. In this work, the synthesis of highly lipophilic quercetin esters with oleic, linoleic and linolenic acid useful as topical quercetin prodrugs is reported. Partial OH esterification is advisable to maintain the antioxidant activity of these compounds; tetraesters and triesters can be achieved by modulating the reaction conditions utilized for the total esterification of quercetin. The chemical structures of the esters were proven by spectroscopic techniques; quantum chemical NMR calculation were mandatory to unequivocally assign the free position in triesters. Finally, the antioxidant activity of all the synthesized compounds was determined by the 2,2-diphenyl-1-picryl-hydrazyl method and by 2,2-azinobis(3-ethyl-benzothiazoline-6-sulfonic acid) assay.

Beschreibung: Acetic- and butyric-capped oleic estolide 2-ethylhexyl (2-EH) esters were synthesized in a perchloric acid catalyzed (0.05 equiv) one-pot process from industrial 90 % oleic acid and either acetic or butyric fatty acids at two different ratios. This was directly followed by the esterification process incorporated into an in-situ second step to provide a low viscosity estolide ester functional fluid. The monoestolide and polyestolides were separated via vacuum distillation (6–13 Pa) at 240–250 °C. The physical properties of these materials were followed throughout the synthetic process and are reported. The final low viscosity acetic- and butyric-capped monoestolide 2-EH esters had viscosities of 19.9 and 24.2 cSt at 40 °C and 4.8 and 5.5 cSt at 100 °C with viscosity indexes (VI) of 161 and 163, respectively. Both monoestolide esters displayed excellent pour points (PPs). The PPs of the two were as follows: acetic-capped estolide 2-EH ester PP = −45 °C and butyric-capped estolide 2-EH ester PP = −27 °C. The biodegradable short-capped oleic estolide 2-EH esters had excellent low temperature properties and should perform well in low viscosity applications.

Beschreibung: Thirty-four strains of docosahexaenoic acid (DHA)-producing microorganisms were newly isolated from brackish areas in Japan. These strains showing various compositions of fatty acids. Especially, the fatty acids produced by one of the strains, named D31, had a high DHA content (over 60 % of the total fatty acids) and the simple fatty acid composition (16:0, 18:0, 18:1 and DHA without any other polyunsaturated acids). Although most oleaginous microorganisms accumulate DHA as triacylglycerol, the strain D31 accumulated DHA mainly as a polar lipid (79.4 % of total DHA), especially as phosphatidylcholine (71.4 % of polar DHA). This strain D31 was identified as a related species of Crypthecodinium cohnii on the basis of phylogenetic analysis. Crypthecodinium sp. D31 showed high DHA productivity when cultivated in a medium containing glycerol as the carbon source and a mixture of yeast extract and polypeptone as the nitrogen sources, with a salinity that was equivalent to 50 % of that of seawater and a pH in the acidic range (〈pH 6.0). Crypthecodinium sp. D31 is considered as a promising producer of high-purity DHA-containing phospholipids.

Beschreibung: CLA-rich soy oil (CLARSO) has been produced by linoleic acid isomerization in soy oil TAG. The objective was to determine the physicochemical properties of the novel CLARSO relative to conventional refined bleached deodorized soy oil (RBDSO). Iodine value decreased in CLARSO samples despite unsaturation being unchanged, probably because conjugated double bonds in triacylglycerol (TAG) of CLARSO impede the complete addition of iodine. Thermal analysis by differential scanning calorimetry showed the melting point temperature increased with the increase in the CLARSO CLA concentration, and melting point broadening occurred in CLA contained samples. Dynamic viscosity of CLARSO conducted from 4 to 44 °C increased with the increase in CLA concentration, relative to RBDSO. Greatest viscosity differences occurred at the lower temperatures. Refractive indices and density were not greatly affected. The change in physical properties was attributed to the increased intermolecular hydrophobic interaction force due to conjugated double bonds and trans , trans isomers, relative to RBDSO. This may provide hard fat characteristics that may be useful for use in producing margarine or shortenings. Furthermore, the higher viscosity at refrigerator temperatures may be useful in salad oil and refrigerated sauces to enable suspension of particles and maintain a rich, thicker texture.

Beschreibung: For better understanding of the adhesive properties of different fractions of cottonseed protein, cottonseed meals from both glanded and glandless cotton varieties were separated into several fractions. Each meal was sequentially extracted with water and 1 M NaCl solution, or with phosphate buffer and NaCl solution. Adhesives were prepared from the recovered fractions and hot-pressed onto maple veneer strips and tested for their properties. The adhesive strength of the water- and buffer-washed solid fractions (i.e., the un-extractable residues of the meals) from the glanded seed ranged from 1.32 to 1.62 MPa and were unchanged or increased compared with the adhesive strength of the original meal that varied from 0.98 and 1.49 MPa. Soaking the wood specimens bonded at 80 °C revealed that the water resistance of these water- and buffer-washed adhesives was significantly improved in that they exhibited no delamination during soaking compared with the meal adhesive that showed some delamination (20–30 % of the samples). Furthermore, the water resistance of these fractions with wet shear strength around 1.5 MPa was comparable to that of cottonseed protein isolate (〉90 % protein) when the joints were bonded at 100 °C. The preparations from glandless cottonseed meals showed similar adhesive performances. Additional extraction of the meals with NaCl solution reduced adhesive performance. The results suggest that water- or buffer-washed cottonseed meal fractions can be used as wood adhesives and would be less costly to prepare than cottonseed protein isolates.

Beschreibung: In this study, seeds from the safflower variety called “Dinçer” were roasted and microwaved before oil extraction by cold pressing. Some physico-chemical analyses (moisture, ash, oil content and color) were performed in safflower meals. Physico-chemical properties (refractive index, viscosity, turbidity, specific gravity, color, free acidity, peroxide value, iodine number), nutritional components (total phenolics, antioxidant capacity, tocopherol content), sterol composition and fatty acid composition of produced oils were also determined. Volatile components of the oils were detected by solid-phase microextraction/gas chromatography–mass spectrometry technique. Quantitative descriptive analysis was accomplished with trained panelists by 11 definition terms. Cold pressing yielded less oil than solvent extraction, but oil quality was superior and a refining process was not required. There was no significant difference between samples for fatty acid composition and some physico-chemical parameters. Whereas, microwave treatment caused a decrease in oil turbidity, free acidity, α-tocopherol and some sterol contents and an enhancement in total phenolic content, antioxidant capacity and peroxide value. Moreover, microwave treatment led to an increased nutty aroma in the oil. In contrast, isot pepper aroma was decreased by microwave treatment. This study provides very important information about the safflower oils for the first time in the literature.

Beschreibung: We performed differential scanning calorimetry (DSC) and synchrotron radiation X-ray diffraction (SR-XRD) experiments of polymorphic structures and binary mixing characteristics of the enantiomers of 1-oleoyl-2,3-dipalmitoyl- sn -glycerol (S-OPP) and 1,2-dipalmitoyl-3-oleoyl- sn -glycerol (R-PPO). In the two enantiomers, oleic and palmitic acid moieties are asymmetrically connected at the sn -1 and sn -3 positions of the glycerol groups, with palmitic acid moiety at the sn -2 position. Pure enantiomer samples (〉99 %) were synthesized and employed throughout this study. The following results were obtained. (1) A basic feature of the mixture systems of S-OPP and R-PPO is of a eutectic nature due to different polymorphic structures of two enantiomers and the racemic compound of PPO ( rac -PPO). (2) Polymorphic behavior of S-OPP and R-PPO was quite similar, both having α-2 and β′-3, whereas rac -PPO contained α rac -3, β′ rac -2, and β′ rac -3. The DSC measurements showed that the melting points of β′-3 (S-OPP = 35.3 °C and R-PPO = 34.9 °C) were higher than that of β′ rac -3 (31.0 °C). β was not crystallized in the pure enantiomers, and rac -PPO. (3) α rac -3 was crystallized at low cooling rates (~2 °C/min), whereas α-2 of the two enantiomers was crystallized only with very rapid cooling (~10 °C/min). (4) Triple-chain-length structures were formed in α rac -3, β′ S -3 (=β′ R -3), and β′ rac -3; α-2 with a double-chain-length structure was formed in both enantiomers. These results indicate the importance of the relationship between subcell packing and glycerol conformation in the polymorphism and mixing characteristics of asymmetric unsaturated–saturated-saturated mixed-acid triacylglycerols.

Beschreibung: Among oil compounds, fatty acids, tocopherols and xanthophylls (lutein and zeaxanthin) are of special interest due to their nutritional properties. The identification and quantification of these compounds in pecan nuts ( Carya illinoinensis ) could therefore be very useful to produce functional foods rich in compounds of this type. This paper reports studies on their accumulation and the effect of ripening on the content of these high value-added compounds. The total lipid content increased during the ripening. Saturated and polyunsaturated fatty acids decreased significantly, whereas, monounsaturated fatty acids increased during the ripening of pecan nut fruit. Maximum levels of total tocopherol (279.53 mg/kg oil) and xanthophyll (6.18 mg/kg oil) were detected at 20th weeks after the flowering date. These amounts decreased gradually as ripening advances. The early stages of pecan ripening seem to have nutritional and pharmaceutical interests. These results may be useful for evaluating the pecan nut quality and determining the optimal period when the pecans accumulated the maximum of these nutritional and healthy compounds.

Beschreibung: Glycerides obtained from the glycerolysis of soybean oil with crude glycerol were acylated with maleic anhydride at 80–100 °C. Both uncatalyzed and catalyzed reactions with 2-methylimidazole (2-MI) were evaluated. Formation of maleated glycerides was confirmed by 1 H-NMR and FTIR analyses. Consumption of maleic anhydride as a function of time was followed by acid value titration. High conversion (ca. 95 %) of hydroxyl groups was obtained at 90 °C in 60 min without catalyst. Under these conditions, a product with 1.9 maleate moieties per glyceride molecule was obtained. Catalyzed reactions afforded lower conversions of hydroxyl groups and lower maleate yields compared to uncatalyzed reactions.

Beschreibung: Sunflower oil was used for deep frying of potatoes at 170 ± 5 °C and for 8 h per day for 5 days in a fryer with an automatic oil filtration system. Three different frying operations were performed: operation (OP)-1, OP-2 and OP-3; that correspond to the oil unfiltered at the end of each frying day, the oil filtered through the fryer's own filter (passive filtration) and the oil firstly subjected to passive filtration and then filtered through a polyethersulfone membrane modified with hexamethyldisiloxane via radio frequency plasma (75 W-5 min, discharge power–time), respectively. The performance of each operation was investigated in terms of free fatty acids (FFA), conjugated dienoic acids (CD), TOTOX value, total polar content (TPC), Hunter color, viscosity, fatty acid composition, and tocopherol content. The results showed that OP-3 could decrease FFA, CD, TOTOX, TPC, L*a*b* value, viscosity and linoleic acid (18:2)/palmitic acid (16:0) ratio in 29.6, 11.7, 25, 30.8, 6.1*11.3*20.8*, 7.8, 12.2 %, respectively, compared to the unfiltered oil (OP-1). Regenerated oil from OP-3 had a frying life approximately 17 h more than oils from both OP-1 and OP-2.

Beschreibung: A potent antioxidant, anti-inflammatory and anti-mutagenic agent; 4-vinyl-2,6-dimethoxyphenol (canolol) was obtained from canola meal in a significant yield via alkaline (NaOH)/enzymatic (ferulic acid esterase) hydrolysis followed by microwave-assisted decarboxylation. The hydrolysis was carried out either through using canola meal directly as a substrate or by using the 70 % aqueous methanolic extract filtrates. The hydrolyzed extracts underwent RP-HPLC analysis which showed that 81.0 and 94.8 % of the total phenolics were hydrolyzed to sinapic acid after the alkaline hydrolysis of the meal and the methanolic extracts, respectively. The enzymatic hydrolysis showed lower conversion rates (49.5 and 58.3 %). The hydrolyzed extracts were consequently decarboxylated using 8-diazabicyclo[5.4.0]undec-7-ene under microwave irradiation at different conditions. The HPLC profiling of decarboxylated extracts showed that using microwave at 300 W of microwave power for 12 min brought the highest sinapic acid conversion to canolol (58.3 %) yielding 4.2 mg canolol from each gram of canola meal suggesting that the process could be commercially economical.

Beschreibung: In the margarine and butter industry, sustainable and more efficient refrigerants, such as CO 2 , are introduced to industrial scraped surface heat exchangers, allowing an increased capacity compared to conventional use of NH 3 . The effect of such changes in capacity and a varied rotational speed was studied in relation to the structural behavior of puff pastry butter during 4 weeks of isothermal storage at 20 °C. The physical properties of the fat crystal network were studied in detail at several length scales by combining X-ray diffraction with differential scanning calorimetry, confocal laser scanning microscopy, LR-NMR and rheology. Our data shows that a high capacity combined with high rotational speed decreases the brittleness of puff pastry butter after 7 days of storage. This effect is, however, diminished after 28 days of storage. Likewise, changes in capacity and rotational speed are shown to induce no microstructural and polymorphic differences after 28 days of storage. However, the degree of work softening is related to the manufacturing conditions: a high capacity and a high rotational speed increase the ability of the puff pastry butter to resist structural breakdown during working. With this being the only observed difference; a wide operational window exists on an industrial level to produce puff pastry butter with similar structural behavior.

Beschreibung: Soy protein adhesives with a high solid content (28–39 %) were extracted from soy flour slurry modified with sodium bisulfite (NaHSO 3 ) at different concentrations. 11S-dominated soy protein fractions (SP 5.4) and 7S-dominated soy protein fractions (SP 4.5) were precipitated at pH 5.4 and pH 4.5, respectively. The objective of this work was to study the effects of NaHSO 3 on adhesion and physicochemical properties of soy protein. The adhesion performance of NaHSO 3 -modified SP 4.5 was better than SP 5.4; the wet strength of these two fractions was from 2.5 to 3.2 MPa compared with 1.6 MPa of control soy protein isolate. SDS-PAGE results revealed the reducing effects of NaHSO 3 on soy protein. The isoelectric pH of soy protein decreased as NaHSO 3 increased due to the induced extra negative charges (RS-SO 3 − ) on the protein surface. The rheological properties of soy protein adhesives were improved significantly. Unmodified samples SP 5.4 and SP 4.5 had clay-like properties and extremely high viscosity, respectively; with 2–8 g/L NaHSO 3 modification, both SP 5.4 and SP 4.5 had a viscous cohesive phase with good flowability. Overall, NaHSO 3 -modified soy protein adhesives in our study have many advantages over the traditional soy protein isolate adhesive such as better adhesion performance, higher solid content but with good flowability and longer shelf life.

Beschreibung: Steryl ferulates (SFs) are ferulic acid esters of phytosterols and/or triterpene alcohols which have potential as frying oil antioxidants. The objective of this study was to evaluate the anti-polymerization and antioxidant activity at frying temperatures of corn steryl ferulates (CSFs), rice steryl ferulates (oryzanol), and a mixture of CSFs with oryzanol, alone and with tocopherols. Antioxidant activity was measured by the reduction of polymerized triacylglycerol formation, and loss of olefinic and bisallylic protons from fatty acid double bonds by 1 H NMR. CSFs and oryzanol slowed the oxidation and polymerization of soybean oil triacylglycerols heated to 180 °C more effectively than a mixture of alpha and gamma tocopherols. CSFs were more effective at preventing polymerization than oryzanol, but when oryzanol was combined with tocopherols, they all had similar antioxidant activity. In addition, tocopherols had a protective effect on SFs. Corn SFs were degraded more quickly during heating than oryzanol, however, the phytosterol constituents of corn SFs, sitostanol and campestanol, were actually more resistant to degradation compared to the phytosterol constituents of rice SFs. Results demonstrate that corn and rice SFs may be effective antioxidants for use in frying oils, and that their activity is enhanced in the presence of tocopherols.

Beschreibung: Dietary phosphatidylinositol (PI) can be synthesized via phospholipase D (PLD)-catalyzed transphosphatidylation of phosphatidylcholine (PC), abundant in soy lecithin, with myo-inositol. However, a generated mixture of phospholipid (PL) classes poses a challenge for analysis. Our current work on Streptomyces PLD engineering requires a robust analytical method for profiling of PI and related PLs derived from the transphosphatidylation reactions. Therefore, we optimized an HPLC-based method with charged aerosol detector (CAD) for PL quantification. PLs were separated on a normal phase silica column by a gradient elution system using two solvents containing chloroform/methanol/1 M formic acid–triethylamine buffer in different ratios. Retention times of the PL standards and LC–MS under identical conditions were used to identity PL classes. PL standards gave linear response in 100- and 10-fold (lyso-PI) concentration range. The method provided a simple, sensitive, repeatable, and precise analysis of PI, PC, phosphatidylethanolamine, phosphatidic acid, and lyso forms of PC and PI. Compared to the similar existing method, introduction of CAD provided a three- to fivefold decrease at the lower end and a two- to fivefold increase at the upper end of the dynamic range. High precision, high sensitivity, and low limits of detection and quantification further underline the benefits of CAD in PL analysis.

Beschreibung: Frying is a popular practice because of its unique sensory characteristics and low cost. The high temperature reached with this cooking method alters molecules present in the oil. The deterioration of the oil depends primarily on its chemical composition. The aim of this study was to evaluate the thermal stability of high oleic sunflower oil (HOSO), sunflower oil (SO) and mixed oil (MIX) during deep frying of French fries. Octanoic acid and unsaturated fatty acid (UFA)/saturated fatty acid (SFA) ratio showed a good correlation with total polar compounds (TPC) for all frying samples analyzed. HOSO and MIX were characterized by reduced levels of thermal degradation, while SO resulted in the highest values of oxidation products (highest TPC values). SO was also the oil more retained by the food matrix, whereas MIX was the least absorbed. HOSO and MIX, having a high oleic acid content (77.58 and 59.92 %, respectively) and a low linoleic acid content (13.42 and 25.70 %, respectively), showed the best characteristics for the frying process.

Beschreibung: Acrolein, which is an irritating and off-flavor compound formed during heating of vegetable oils, was estimated by the gas–liquid chromatography (GLC). Several vegetable oils such as high-oleic sunflower, perilla, rapeseed, rice bran, and soybean oils were heated at 180 °C for 480 min and then the concentration of acrolein in the head space gas was determined by GLC. The formation of acrolein was greatest in perilla oil among the tested oils, while it was much lower in rice bran oil and high-oleic sunflower oil. There was a good correlation between the level of acrolein and linolenate (18:3n-3) in the vegetable oils. To investigate the formation of acrolein from linolenate, methyl oleate, methyl linoleate, and methyl linolenate were also heated at 180 °C, and the amounts of acrolein formed from them were determined by GLC. The level of acrolein was the greatest in methyl linolenate. Acrolein was also formed from methyl linoleate, but not from methyl oleate. Acrolein in vegetable oils may be formed from polyunsaturated fatty acids, especially linolenic acid but not from glycerol backbone in triacylglycerols.

Beschreibung: γ-Decalactone is an industrially interesting peach-like aroma compound that can be produced biotechnologically through the biotransformation of ricinoleic acid. Castor oil (CO) is the raw material most used as the ricinoleic acid source. The effect of different CO concentrations on the γ-decalactone production by Yarrowia lipolytica was investigated in batch processing, and 30 g L −1 was found to be the optimal oil concentration. Under these conditions, cells were able to produce lipase but at low activity levels, which might limit ricinoleic acid release and consequently, the γ-decalactone production rate. Thus, the enzymatic hydrolysis of CO by commercial lipases was studied under different operating conditions. Lipozyme TL IM was found to be the most efficient and the optimal hydrolysis conditions were pH 8 and 27 °C. The use of hydrolyzed CO in the aroma production allowed a decrease in the lag phase for γ-decalactone secretion.

Beschreibung: Three phosphonate derivatives of methyl oleate (MeO) were chemically synthesized in a radical chain reaction and their physical and tribological properties investigated. The phosphonates differed from each other in the structure of the alkoxy groups attached to the phosphorous, which were as follows: methoxy, ethoxy, and n -butoxy. Phosphonylation eliminated the unsaturation in MeO and also introduced branching. The phosphonate oils had higher density and viscosity than MeO, which was attributed to the contribution of the heavier phosphorus atom in their structures, and to their higher molecular weights, respectively. The phosphonates also displayed improved oxidation stability and cold flow properties, which were attributed to the elimination of the double bond and the introduction of branching in their molecular structures, respectively. Tribological investigations were conducted using 4-Ball anti-wear (AW) and extreme pressure (EP) methods. Neat phosphonates displayed lower AW coefficients of friction and wear scar diameters than MeO. The improved AW results were attributed to the higher viscosity of the phosphonates, since the AW test is conducted in the mixed film regime. The phosphonates had no effect on EP weld point (WP) as neat oils or as 5 % additives in petroleum-based oils. In soy base oil, 5 % phosphonate additives displayed smaller improvement in WP than zinc dialkyl dithiophosphate (ZDDP). It is proposed that this lack of EP characteristics could be due to the high dissociation energy of C–P bonds in the phosphonates, compared to, for example, S–P bonds in ZDDP.

Beschreibung: The present study presents the antioxidant activity of sesamin in canola oil compared with that of butylated hydroxytoluene (BHT) by monitoring the oxygen consumption and the decrease in linoleic acid and α-linolenic acid. The oxidation of canola oil was conducted at 35, 60, 90, 120 and 180 °C with addition of 50–400 ppm sesamin. Results from the oxygen consumption test showed that sesamin dose-dependently inhibited the oxidation of canola oil at concentrations of 50–200 ppm at temperatures of 60–180 °C, however, sesamin lost its antioxidant activity at a low temperature of 35 °C. The fatty acid analysis also demonstrated that sesamin at 50, 100 and 200 ppm dose-dependently prevented the oxidation of linoleic acid and α-linolenic acid in canola oil. Both the oxygen consumption and the fatty acid analysis demonstrated sesamin was less effective than BHT as an antioxidant at temperatures of 60–180 °C. It was therefore concluded that sesamin could prevent the lipid oxidation of frying fats and oil, however, its antioxidant activity was not as potent as that of BHT.

Beschreibung: Biodiesel is a biofuel obtained from vegetable oils. The oils used as raw materials are usually refined edible vegetable oils. Nonedible acidic oils are unsuitable for biodiesel production unless reduction of the high content in free fatty acids (FFA) of these materials had been achieved. Obtaining a good raw material from unprofitable oils becomes an important research field. Additionally clays have a long history in industrial sorption and catalysis, some being commercially available and with properties that can be modified. In this work we present the results of the use of the montmorillonite clay K10 and two acid modified clays K10(I) and K10(II), in the esterification of stearic acid with methanol and 95 % of methyl stearate was obtained with K10(II). These clays were then used for the first time to reduce the acidity of enhanced FFA sunflower oil and they show to be very effective. Reduction of FFA from 11 to 4 % was obtained with K10(II) mainly due to 94 % conversion of FFA into fatty acid methyl esters (FAME). These clays were also tested with two waste oils, one from domestic use and the other gathered from different restaurants, and showed their ability to lower the acidity of these oils. Reactions were followed by 1 H NMR as well as quantitative determination of FFA and FAME. Clays were characterized by FTIR and XRD.

Beschreibung: The objective of this work was to develop a corrected method for solid fat content estimation by differential scanning calorimetry (DSC), as important differences are usually observed between the results given by DSC and pulsed nuclear magnetic resonance (NMR). Cold storage after full melting of fats was necessary to avoid the appearance of exothermic peaks in the modulated temperature DSC thermograms, in order to make an appropriate estimation of melting energy. Different fats were analyzed by NMR and DSC, obtaining considerably higher solid fat content values with the latter, uncorrected method. These differences were attributed to the fact that consumed energy per unit of melted mass tends to increase with the increase of the melting temperature of each fraction of the fats. A linear correlation between melting enthalpy and melting point of different triglycerides was used to estimate the energy per unit of mass consumed at each temperature. From these data, an estimated transformation of melting energy into melted mass was performed and new solid fat content values were calculated. The results obtained from this correction were much closer to the measurements made by NMR, in comparison to the uncorrected DSC method.

Beschreibung: Diphenylamine sulfate (DPAS) and diphenylamine hydrochloride (DPACl) salts were found to be highly active catalysts for esterification and substantial transesterification of inexpensive greases to fatty acid methyl esters (FAME). In the presence of catalytic amounts of DPAS or DPACl and excess methanol, the free fatty acids as well as the acylglycerols in waste greases were converted to FAME at 125 °C within 1 h. Although the DPAS and DPACl catalysts were found to have similar catalytic activities to their parent liquid acids (i.e., sulfuric and hydrochloric acids) the diphenylammonium salts are much easier to work with than concentrated liquid acids.

Beschreibung: The aim of this study was to examine the oxidation of selected plant oils in concentrated beverage emulsions colored with natural β-carotene. Carotenoid preparations obtained from carrots were dissolved in cold-pressed linseed oil, refined canola oil, and refined palm olein. Oxidative stability of the lipids was examined with and without addition of the pigment to the oil/water (O/W) emulsion. Carotenoid/lipid hydro peroxide (LOOH) concentration was evaluated using two different methods: LOOH + Fe 2+ reaction connected with a colored complex of ammonium thiocyanate determined with the help of a spectrophotometer, and LOOH determined with the help of a chemiluminometer. It was shown that oxidation rate of lipids in the O/W emulsions strongly depended on chemical composition of the lipid fraction (type of oil used). Presence of the carotenoid pigment increased the rate. Therefore, if a carotenoid-containing emulsion is to be stable, it should be based on oils of a high oxidative stability.

Beschreibung: This work investigated whether ultrasound treatment could improve the oil recovery from the extract obtained from pressed oil palm mesocarp. Oil recoverable after subjecting two process streams from palm oil milling operations to ultrasound were compared to that obtained from corresponding samples without ultrasound treatment. The process streams examined were (i) the ex-screw press feed into the vertical clarification tank and (ii) the underflow sludge from the clarification tank. Oil recoverable was taken as the sum of decantable oil obtained after a gravity settling process at 85 °C for 1 h (skimmed oil) and oil released from the remaining colloidal dispersion after centrifugation at 1,000 g (centrifuged oil). Oil recoverable was dependent on the ultrasound treatment applied, type of transducer used and the feed stream. Increased recoverable oil was obtained by applying low frequency ultrasound (20 kHz) to the ex-screw press feed using a long rod radial sonotrode system but recoverable oil was decreased when a short single step cascade focused sonotrode system was used. High frequency ultrasound (400 + 1,600 kHz) increased recoverable oil from both process streams. Applying sequential low and high frequency ultrasound increased recoverable oil from the ex-screw press feed but decreased that from the underflow sludge. The use of high frequency ultrasound for improving oil recovery is a significant advance for palm oil milling operations.

Beschreibung: Conditioning rapeseed can significantly increase the amount of bioactive compounds in the crude oil, but if the conditioning temperatures are too high, they can cause unwanted side effects such as darker color and sensory defects. Modest conditioning temperatures may be more suitable, but little is known about the effects on the quality and bioactive composition of the resulting oil. Oil was recovered from five rapeseed cultivars by cold pressing (CP) or by pressing seeds conditioned at 80 °C for 30 min (HP). Conditioning rapeseed increased oil yield without changing fatty acid composition and increased the amount of total sterols by 16 %, total tocopherols by 20 %, and the levels of polyphenols. Levels of the polyphenol canolol were up to 55-fold higher in HP oil than in CP oil. These higher levels of bioactive compounds gave HP oil higher radical scavenging activity. Although HP oil also had higher free fatty acid contents, peroxide levels, and specific UV extinctions ( K values). The quality parameters of HP and CP oils were within codex limits indicating high quality. Modest conditioning temperatures can be used to produce rapeseed oil with high quality and radical scavenging activity.

Beschreibung: Ten 1,3-dialkylimidazolium-based ionic liquids (ILs) have been investigated as media for the enzymatic synthesis of tricaprylin, in comparison with the conventional organic solvent hexane. The results suggested that the esterification activity of Novozym 435 was higher than Lypozyme RM IM in all the ILs assayed. Novozym 435 showed higher catalytic activity in ILs with anions Tf 2 N − and PF 6 − than in BF 4 − and hexane. FTIR analysis of the secondary structure of the lipase indicated that a smaller decrease of the α-helix was observed in [C 4 MIM] Tf 2 N and [C 4 MIM] PF 6 than [C 4 MIM] BF 4 and hexane, indicating that the anions of ILs might be a key factor for the activity of lipase in ILs. Process parameters (amount of lipase, caprylic acid/glycerol molar ratio, temperature and their interactive effects) were optimized in 1-butyl-3-methylimidazolium hexafluorophosphate ([C 4 MIM]PF 6 ) using Novozym 435 by response surface methodology. When the reactions were performed with the lipase amount of 6.1 % substrate mass at a caprylic acid/glycerol molar ratio of 4.5:1 and 66.7 °C, a higher yield was reached up to 92.4 %.

Beschreibung: The development of sensitive and robust screening tool(s) for assuring the quality of incoming raw materials would supplement the assurances provided by food manufacturer vendor auditing programs. Our aim was to evaluate the ability of attenuated total reflectance mid-infrared (ATR-MIR) spectroscopy in combination with multivariate analysis as a screening tool for the diverse cocoa butter supply. Forty different cocoa butter samples encompassing an acceptable range of compositional variability for the chocolate industry were included. Cocoa butters were characterized for their melt characteristics (melting heat), triacylglycerol content and fatty acid composition (GC-FAME). Soft independent modeling of class analogy (SIMCA) and partial least squares regression (PLSR) were used for classification and quantification analysis. SIMCA classified all cocoa butters in distinct clusters in a 3-dimensional space but no sample clustering patterns were associated with melt characteristics. Spectral differences responsible for the separation of classes were attributed to stretching vibrations of the ester (–C=O) linkage (1,660–1,720 cm −1 ). PLSR models showed correlation coefficients 〉0.93 and prediction errors (SECV) of 1.5 units for melt characteristics, 0.2–0.3 and 0.4–0.8 % for major fatty acids and triacylglycerols, respectively. ATR-MIR spectroscopy combined with pattern recognition analysis provides robust models for characterization and determination of cocoa butter composition.

Beschreibung: The influence of temperature on the fatty acid composition of the oils from conventional and high oleic sunflower genotypes grown in tropical regions was evaluated under various environmental conditions in Brazil (from 0° S to 23° S). The amounts of the oleic, linoleic, palmitic and stearic fatty acids from the sunflower oil were determined using gas chromatography (GC). The environment exhibited little influence on the amounts of oleic and linoleic fatty acids in high oleic genotypes of sunflower. In conventional genotypes, there was broad variation in the average amounts of these two fatty acids, mainly as a function of the minimum temperature. Depending on the temperature, especially during the maturation of the seeds, the amount of oleic acid in the oil of conventional sunflower genotypes could exceed 70 %. Higher temperatures led to average increases of up to 35 % for this fatty acid. Although the minimum temperature had the strongest effect on the fatty acid composition, locations at the same latitude with different minimum temperatures displayed similar values for both oleic acid and linoleic acid. Furthermore, minimum temperature had little influence on the amounts of palmitic and stearic fatty acids in the oil.

Beschreibung: To better understand the effects of water properties on the reaction characteristics of acrolein production from glycerol, dehydration of refined glycerol and crude glycerol was comparatively conducted in both sub- and super-critical water states, and the effect of changing water properties was studied to optimize the reaction conditions. The effects of reaction temperature, pressure, residence time, water/glycerol ratio, and catalyst concentration on the yields and distribution of chemical products were also examined. Acrolein yield 〉80 mol% from both refined glycerol and crude glycerol can be achieved by controlling water properties in the sub-critical water state with the addition of sulfuric acid as a homogeneous catalyst and the formation of undesired acetaldehyde and propionaldehyde can be greatly restrained. These results provide valuable information for the production of value-added chemicals from crude glycerol.

Beschreibung: The extraction efficiency of microalgae lipids with aqueous isopropanol (IPA) was investigated and compared with the extraction of oil from full-fat soy flour. The effects of the type of microalgae ( Scenedesmus sp. and Schizochytrium limacinum ), cell rupture, and IPA concentration on the yield of oil and non-lipid biomass were determined. The oil yield from intact cells of Scenedesmus was 86–93 % with 70, 88, or 95 % (by wt) IPA. Ultrasonic cell rupture prior to oil extraction decreased the oil yield of Scenedesmus to 74 % when extracting with 70 % IPA. The oil yield from intact cells of S. limacinum was 〈23 % regardless of the IPA concentration, but ruptured cells gave a 94–96 % oil yield with 88 or 95 % IPA. The different response of the two microalgae to extraction with IPA is possibly caused by differences in the cell wall structure and type and amount of polar lipids. The oil yield from soy flour with 88 and 95 % IPA was 93–95 %, which was significantly greater than yields with 50 and 70 % IPA. Cell rupture had no effect on soy flour extraction. In general, the oil yield from the ruptured cells of both microalgae and soy flour increased with increasing IPA concentration.

Beschreibung: An interlaboratory study was conducted to evaluate a method for determining glycidyl fatty acid esters (GE) in edible oils. Samples were dissolved in tert -butyl methyl ether/ethyl acetate and subjected to two solid-phase extraction (SPE) steps. The first SPE step utilized methanol elution from a C18 cartridge, and the second SPE step utilized n -hexane/ethyl acetate elution from a silica cartridge. The final extract was analyzed using liquid chromatography with a single quadrupole mass spectrometer in selected ion monitoring (SIM) mode. Quantification was performed using external standardization. Eighteen samples (9 oils × 2 blind duplicates) were assayed for glycidyl palmitate, glycidyl stearate, glycidyl oleate, glycidyl linoleate and glycidyl linolenate by 17 collaborating laboratories from seven countries. Sample matrices included palm, olive, corn, soybean and rapeseed oils. Repeatability (RSDr) ranged from 6.85 to 19.88 % and reproducibility (RSDR) ranged from 16.58 to 35.52 % for samples containing greater than 0.5 mg/kg of individual GE. HORRAT R values ranged from 0.62 to 14.70 for determination of total GE. The method provides acceptable results for quantification of GE in edible oils.

Beschreibung: Milk fat is known to contain one of the highest number of fatty acids of all edible oils. Some of these fatty acids are known to be valuable (e.g. conjugated linoleic acids, furan fatty acid) and other as undesirable (e.g. saturated and some trans -fatty acids) food ingredients. However, a comprehensive picture on the presence of many trace fatty acids has not been achieved. For this reason we have developed an analysis scheme based on the conversion of the fatty acids into methyl esters. The fatty acid methyl esters were then fractionated by urea complexation. Both the filtrate of the urea complexation (~4 % of the sample weight) and the original sample were fractionated by high-speed counter-current chromatography (HSCCC). The resulting fractions were analyzed by GC/MS analysis. With this method 430 fatty acids were detected in one single butter sample. More than 230 fatty acids had two or more double bonds. In addition to the widely known spectrum of fatty acids we also detected a range of cyclohexyl fatty acids (five homologues) and methyl-branched fatty acids (including short chain and even-numbered anteiso -fatty acids), conjugated tetradecadienoic acids along with the novel ω-oxo-fatty acids (seven homologues). The reported relative retention time on the polar column may serve as a data base for the screening of other samples for this profusion of fatty acids.

Beschreibung: Fatty acid methyl ester sulfonate (MES), an anionic surfactant suitable as a laundry detergent, is produced commercially by the direct sulfonation of fatty acid methyl ester (ME) with SO 3 . However, intense coloration occurs during the sulfonation process. The sulfonation of ME was performed through the addition of SO 3 (SO 3 /ME molar ratio = 0.8–1.2) for 1–4 h and subsequent aging for 1 h at 80 °C. Even when the amount of unsaturated bonds in ME was reduced to give an iodine value (IV) of less than 0.01, coloration occurred during the sulfonation, making the unbleached product unsuitable for commercial use. The formation of olefinic units and SO 2 was observed during the reaction, and the color of the reaction mixture was strongly correlated with their amounts. Further analysis confirmed that equimolar amounts of the olefinic unit and SO 2 were formed, and the rate profiles of the formation of MES and SO 2 agreed well with each other. From these observations, we concluded that the coloration of the reaction mixture was caused by oxidation of the alkyl chain with SO 3 during the liberation of SO 3 from the 1:2 adduct of ME and SO 3 , a key intermediate in the sulfonation process.

Beschreibung: Lipid compositions of two non-conventional oilseeds ( Irvingia gabonensis and Treculia africana ) were studied. Total lipids were extracted by the Folch method and phospholipids were isolated by solid phase extraction. Fatty acid compositions of total lipids and phospholipids were determined by gas chromatography. Phospholipid classes and tocopherols were quantified by HPLC. The major fatty acids in I. gabonensis seed total lipids were myristic (41.4–48.9 %) and lauric (39.8–46.8 %) while those in T. africana seed were linoleic (29.1–31.4 %) and oleic (22.9–25.9 %). The principal fatty acid at the sn -2 position of I. gabonensis seed triacylglycerols was myristic (49.5 %) while that of T. africana was linoleic (50.6 %). Phospholipid content of crude T. africana seed oil was 3.3 % and that of I. gabonensis was 0.1–0.3 %. The composition and distribution of saturated fatty acids in I. gabonensis seed lipids suggest that it may contribute to cardiovascular disease risk factors among the Igbo people in Nigeria that use the seed as food ingredient.

Beschreibung: External laminar oscillatory shear applied during crystallization in combination with different temperature fields was used to modify the microstructure and physical properties of edible oil organogels. Crystallization at a high cooling rate (30 °C/min) resulted in a spherulitic microstructure with a higher oil-binding capacity, lower storage modulus and lower yield stress compared with a material (with a fibrillar microstructure) crystallized at a slow cooling rate (1 °C/min). The application of an oscillatory shear resulted in the formation of novel microstructures depending on the cooling regime used. The application of an oscillatory shear (strain 〉 500 % and frequency = 1 Hz) resulted in the thickening of fibers observed in the slow-cooled material and an increased incidence of spherulite nucleation in the rapidly cooled material. Increasing the frequency of the oscillatory shear applied did not change the microstructure for the slow-cooled gel but further increased the incidence of nucleation for the rapidly cooled gel. The application of controlled-strain oscillatory shear to the crystallizing gel at either cooling rates resulted in an oily and very soft, paste-like material. This material had a lower storage modulus and poorer oil-binding capacity compared with the same gel crystallized statically. Reduction of the oscillatory strain from a maximum of 1500 to 500 % moderately mitigated the loss of mechanical properties and oil-binding capacity although these properties were in no way comparable to those obtained from static crystallization. The study shows that the application of oscillatory shear and different cooling regimes can be used to tailor a crystalline organogel. However, the application of continuous shear must be done with care as application of excessive shear can result in a complete breakdown in gel structure and large amounts of oil loss.

Beschreibung: The fatty acid profile of kenaf ( Hibiscus cannabinus L.) seed oil has been the subject of several previous reports in the literature. These reports vary considerably regarding the presence and amounts of specific fatty acids, notably (12,13-epoxy-9( Z )-octadecenoic (epoxyoleic) acid, but also cyclic (cyclopropene and cyclopropane) fatty acids. To clarify this matter, two kenaf seed oils (from the Cubano and Dowling varieties of kenaf) were investigated regarding their fatty acid profiles. Both contain epoxyoleic acid, the Cubano sample around 2 % and the Dowling sample 5-6 % depending on processing. The cyclic fatty acids malvalic and dihydrosterculic were identified in amounts around 1 %. Trace amounts of sterculic acid were observed as were minor amounts of C17:1 fatty acids. The results are discussed in the context of the fatty acid profiles of other hibiscus seed oils.

Beschreibung: Biodiesel is an alternative fuel composed of mono-alkyl fatty acid esters made from the transesterification of plant oils or animal fats with methanol or ethanol. After conversion, biodiesel may contain trace concentrations of unconverted monoacylglycerols (MAG). These MAG have low solubility in biodiesel and may form solid residues when stored at cold temperatures. The present study evaluates the measurement of kinematic viscosity ( ν ) and cold filter plugging point (CFPP)-time to filter (Δ t ) as parameters that predict the temperature where small concentrations of MAG may lead to formation of solids or other phase transitions that restrict the flow of soybean oil fatty acid methyl esters (SME) through filters and fuel lines. Mixtures of SME doped with MAG were prepared and ν and Δ t were measured as the temperature decreased from 20 to below 0 °C. Results showed a correlation between ν and Δ t that held for neat SME (SME without added MAG) and SME-MAG mixtures as the temperature decreased to the threshold temperature ( T th ). Sharp increases in ∆ t disrupted the correlation as temperature decreased below T th . Furthermore, T th generally increased as added MAG concentration increased in the mixtures.

Beschreibung: Typoselectivity of crude CBD-T1 lipase ( Geobacillus sp. T1 lipase fused with a cellulose binding domain) was investigated. Multi-competitive reaction mixtures including a set of n -chain fatty acids (C8:0, C10:0, C12:0, C14:0, C18:1 n-9, C18:2 n-6 and C18:3 n-3) and tripalmitin-enriched triacylglycerols were studied in hexane. The crude CBD-T1 lipase discriminated strongly against C18:1 n-9 [competitive factor ( α ) = 0.23] and showed the highest preference for C8:0 ( α  = 1). Utilizing the catalytic properties of crude CBD-T1 lipase, acidolysis of soybean oil with C8:0 was selected as a model reaction to investigate the ability of the lipase to produce MLM-type (medium-long-medium) structured lipids. Several reaction parameters (added water amount, reaction temperature, substrate molar ratio and reaction time) examined for incorporating C8:0 into soybean oil, the optimum conditions were: 1:3 (soybean oil/C8:0) of molar ratio, 3 mL of hexane, 50 °C of temperature, 48 h of reaction time, 20 % of crude CBD-T1 lipase (w/w total substrates), and 7.5 % of water (w/w enzyme). Under these conditions, the incorporation of C8:0 was 29.6 mol%. The results suggest that crude CBD-T1 lipase, which showed different fatty acid specificity profiles, is a potential biocatalyst for the modification of fats and oils.

Beschreibung: Food habits worldwide have increased the demand for oxidative-resistant oils that can be used for deep-frying. Oxidative stability in oils can be improved by changing the fatty acid composition of the oil or by adding natural antioxidants to the oil. In this study, the effect of essential oils of seven plants; cinnamon, rosemary, sage, turmeric, clove, thyme and oregano enriched with carvacrol on the oxidative stability of corn oil at frying temperatures were studied. Experiments were conducted by using a PetroOxy device, a rapid small scale oxidation stability test. A central composite design was used to evaluate the effects of concentration of essential oil (X1: 1,500–5,000 ppm) and temperature (X2: 150–180 °C), on the induction time of corn oil. In order to compare the results with the synthetic antioxidant, butylated hydroxy toluene (BHT), another design was made with a concentration range (60–350 ppm) containing the legal upper limit of BHT, 200 ppm. Induction periods obtained from the accelerated oxidation test revealed that increasing temperature decreased the induction time of all the samples. However, the essential oils except for oregano oil had no significant antioxidative effect on corn oil, probably due to a lower content of their active components. The antioxidative effect of oregano oil was also found to be higher compared to BHT. At very high temperatures (e.g., 180 °C), the concentration of antioxidants had no effect on the induction periods.

Beschreibung: Triglyceride-based monomers represent a competitive alternative to petrochemical resources in the macromolecular compounds area. In the current study, several types of hydrophilic camelina oil (CO)-based monomers were synthesized using tunable experimental protocols that involve three different steps: first—conversion of the double bonds into epoxy rings, second—partial opening of the epoxy rings and methacrylic groups grafting and last—opening of the unreacted epoxy rings and hydrophilic units attaching. 1H-NMR, 13C-NMR and FTIR spectroscopy demonstrate the success of the CO functionalization with polymerizable and hydrophilic moieties—polyethylene glycol units—with different molecular weights, exhibiting self-emulsifiable properties. Several bulk and emulsion polymerization tests were performed for the synthesized monomers and their ability to build polymer networks using different photo-chemical procedures (using visible and UV radiations respectively) was demonstrated, without additional surfactants. FTIR spectroscopy indicates the polymerization success by the disappearance of the specific bands assigned to the double bonds from methacrylic groups and thermogravimetric analysis demonstrates that the emulsion polymerization leads to materials with an improved thermostability.

Beschreibung: This study compared two methods for extracting the protein in pennycress ( Thlaspi arvense L.) press cake and determined the composition and functional properties of the protein products. Proteins in pennycress press cake were extracted by using the conventional alkali-solubilization–acid-precipitation (AP) method or saline-based (SE) procedure (0.1 M NaCl at 50 °C). The extraction method has a major influence on the purity and functional properties of press cake protein products. AP had a lower protein yield (23 %) but much higher purity (90 % crude protein) compared with SE (45 % yield, 67 % crude protein). AP protein isolate had high foam capacity (120 ml), high foam stability (96 % foam volume retention) and high emulsion stability (24–35 min), and it was resistant to heat denaturation (3 % loss of solubility at pH 2 and pH 10). On the other hand, SE protein concentrate showed remarkably high solubility (〉76 %) between pH 2 and 10 and exceptional emulsifying activity (226–412 m 2 /g protein), but was more susceptible to heat denaturation at pH 7 and pH 10 (65–78 % loss of solubility). These results strongly demonstrate that higher purity pennycress press cake protein can be produced by either saline extraction or acid precipitation and have functional properties that are desirable for non-food uses.

Beschreibung: Soybean protein powders obtained by aqueous buffer and reverse micelle extractions were examined and characterized using X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and scanning electron microscopy (SEM). These analysis methods provided detailed information about elemental distributions, surface structure, and secondary and microstructures of the protein, respectively. XPS data revealed that the O and N atomic percentages of soybean protein surfaces obtained with bis(2-ethylhexyl) sodium sulfosuccinate (AOT)/hexane reverse micelles were higher than those obtained with aqueous buffer, whereas the percentage of atomic C was lower. The ratios of nitrogen to carbon (N/C) on the surface of soybean protein obtained through the two extraction methods were similar. The O/C ratio for soybean protein obtained from AOT reverse micelles was large. The obtained results indicated that the reverse micelles could affect the C, O, and N components on the surface of soybean proteins. Moreover, XRD and SEM results also showed the influence of AOT reverse micelles, which lead to more β -sheet and pore structures.

Beschreibung: In this work, modified fats were produced by enzymatic interesterification of mutton tallow with walnut oil. As a result of forcing the fat hydrolysis process by addition of water to the enzymatic preparation (11.5, 13.0, 14.5, 16.0 wt %), additional levels of polar fractions (MAGs, DAGs, and FFAs) were observed. The aim of this work was to evaluate the stability of emulsions of modified fats containing natural emulsifiers resulting from enzymatic interesterification of mutton tallow with walnut oil. The physical-chemical parameters of obtained fats were determined in this study. Using several methods, the stability of the formed emulsions was also evaluated. The results showed that the fats resulting from interesterification in the presence of Lipozyme RM IM (immobilized lipase from Rhizomucor miehei , Novozymes Bagsvaerd, Denmark) with 13.0, 14.5, and 16.0 wt % of water in the enzymatic preparation could form stable emulsion systems. On the other hand, the emulsion of the interesterification system where the amount of water in the enzymatic preparation was 11.5 % showed very low stability. The number of natural emulsifiers (MAGs and DAGs) that arose after interesterification was insufficient to stabilize the emulsion system. The work has shown the possibility of using interesterified fats as the fat phase. Emulsions formed on the basis of interesterified fats without any additional emulsifiers such as sunflower lecithin had properties comparable to emulsions containing mixed non-interesterified fat containing additional emulsifier. The natural emulsifiers formed as part of enzymatic interesterification allow formation of stable emulsion systems.

Beschreibung: Soybeans are cultivated in the United States chiefly for cooking oil, while the residue after oil extraction (soybean meal) is mostly used in animal feed formulations. High protein content in the defatted soybean meals led to the extraction of pure protein and its application in food products. We selected 44 soybean lines to determine their moisture and protein contents, and their amino acid composition was investigated. Soybean lines with high protein content, one high yielding (R95-1705), and two high oleic acid (N98-4445A, S03-543CR), were selected for protein isolate preparation, hydrolysis using alcalase and gastro-intestinal (GI) resistance. Furthermore, the GI resistant hydrolysates were fractionated and tested for angiotensin-I-converting enzyme (ACE-I) inhibition activity. The amino acid analysis showed high methionine in the high protein and fatty acid lines (R05-4494 and R05-5491), and high cysteine content in one of the high oleic acid soybean line CRR05-188 in comparison to the check lines (UA-4805 and 5601-T). The protein isolate with the highest purity (90–93 %) was derived from the selected lines N98-4445A and S03-543CR, and hydrolyzed using alcalase enzyme. The protein hydrolysates (500 µg/mL) showed inhibition of the ACE-I by 49 %. The results from this study will promote the use of high oleic acid soybeans as a source of protein and peptides with functional activities.

Beschreibung: Characteristics of crude palm oil are high FFA and DAG contents. High DAG content may affect throughput and yield during fractionation: high-grade specialty fats such as hard palm mid fraction require premium crude palm oil to secure adequate crystallization properties. Moreover, DAGs are generally considered the main precursors for the formation of glycidyl esters during high-temperature deodorization. The purpose of this study was to investigate the effect of enzymatic remediation on the reduction of FFA and DAG in crude palm oil. In practice, series of process parameters (vacuum and reaction time) were investigated, and the quality of enzymatically remediated crude palm oils was examined in terms of FFA and DAG reduction, TAG composition, and SFC and DSC melting profiles. Fully refined enzymatically remediated palm oils were then dry fractionated. The quality of the oleins derived from the enzymatically remediated palm oil was compared to that of regular RBD palm oleins.

Beschreibung: The performance of a portable infrared system combined with pattern recognition to discriminate between organically and conventionally produced bovine butter samples as well as to predict the levels of conjugated linoleic acid (CLA) were evaluated. Sixty butter (27 organic and 33 conventional) samples were used in this study. Bovine butter–fat were applied onto an attenuated total reflectance infrared (ATR-IR) accessory equipped with a five-bounce ZnSe crystal set at 65 °C for spectral collection. In addition, ATR-IR spectra of bovine butter were directly collected at room temperature to avoid phase separation. The fatty acid profile and the levels of CLA were determined using reference FAME-GC-FID analysis. SIMCA models showed well separated clusters that discriminated between organic and conventional bovine butters due to C=C trans bending out of the plane vibration modes band at 967 cm −1 . Additionally, strong PLSR models were developed to predict CLA levels using butter–fat and bovine butter spectra with SEP of 0.05 % and RPD of 4.7, indicating that the models are suitable for quality control applications. Portable IR technology offers the ability for “ in situ ” analysis of butters that is much less time consuming than current analytical practices for authentication and quality control efforts by the industry.

Beschreibung: γ-Stearidonic acid, 18:4n-6, a potential product of β-oxidation of arachidonic acid (20:4n-6), was only recently positively identified in a living organism—a thermophilic cyanobacterium Tolypothrix sp., albeit at low levels, whilst some indirect evidence suggests its wider presence, e.g. in a unicellular marine alga. We have prepared 18:4n-6 using an iodolactonisation chain-shortening approach from 22:5n-6 and obtained its 1 H-, 13 C-, COSY- and HSQC NMR spectra, with 18:5n-3 spectra also recorded for a comparison. The GC and GC-MS behaviour of its methyl ester was also studied. Like another Δ3 polyunsaturated acid, octadecapentaenoic (18:5n-3), 18:4n-6 rapidly yields 2- trans isomer upon formation of dimethyloxazoline derivative. On a polar ionic liquid phase (SLB-IL100, 200 °C) the methyl ester could be mistaken for 18:3n-3, while on methylsilicone phase (BP1, 210 °C) it eluted ahead of 18:3n-6 and 18:4n-3, suggesting that when present it may be easily misidentified during GC analysis of fatty acids.

Beschreibung: Oilseed plants produce huge amounts of fatty acids (FA) stored as triacylglycerols (TAG) in seeds that give a great variation in their composition. The variety and content of TAG directly affect the nutrition and function of lipids. TAG composition of 12 high-oleic and normal peanut oil samples were profiled by two-dimensional liquid chromatography (2D LC) coupled with atmospheric pressure chemical ionization mass spectrometry (APCI-MS). The statistical evaluation of the TAG profiles determined was conducted on the basis of multidimensional data matrix using Principal Component Analysis (PCA). The technique enabled the differentiation of high-oleic oils from normal peanut oils—as results illustrated TAG of high-oleic peanut oil were clearly different from those of normal peanut oils. High-oleic and normal peanut oils had different profiles mainly in the contents of OOO, OPO and POL. This finding provided theoretical foundation for detecting the adulteration of edible oils and analyzing the nutrition and function of high-oleic peanut oils.

Beschreibung: Earlier findings on the nutritional benefits of diacylglycerols (DAGs) have attracted much attention on the synthesis of DAGs. In this study, we reported an improved method for the lipase-catalyzed synthesis of 1,3-diolein by the irreversible glycerolysis of vinyl oleate with glycerol. The effects of reaction system, lipase loading, molar ratio of vinyl oleate to glycerol, reaction temperature and time on 1,3-diolein content in crude reaction mixture were investigated. When the reaction was conducted in a solvent-free system at 30 °C for 8 h by reacting 2 mmol vinyl oleate with 1 mmol glycerol with 8 % (w/w, relative to total reactants) Lipozyme RM IM (Novozymes, Beijing, China) as catalyst, there were 90.5 ± 2.9 % (area/area) 1,3-diolein and (3.3 ± 0.3) % 1,2-diolein produced. After purification, 1,3-diolein was obtained at 81.4 % yield with 98.2 % purity. The lipase-catalyzed synthesis of 1,3-diolein using vinyl oleate as acyl donor by glycerolysis was also conducted using a medium with 50 mmol of glycerol and 100 mmol vinyl oleate. Compared to enzymatic esterification in a solvent, enzymatic glycerolysis for the synthesis 1,3-diolein is more effective due to the irreversible reaction, mild due to the low reaction temperature, and environmentally benign due to the use of solvent-free reaction system.

Beschreibung: This work quantifies the adulteration of ethyl and methyl soybean biodiesels/diesel (B5) blended with soybean oil using mid-infrared spectroscopy associated with multivariate calibration. The models constructed by the method of partial least squares (PLS) presented low values of root-mean-square error of prediction 0.22 % (w/w) and 0.26 % (w/w), respectively, for models containing ethyl and methyl soybean biodiesel. Along with the parameters of error, accuracy was evaluated by the use of an elliptical joint confidence region (EJCR). The EJCR for the both PLS models showed there was no significant difference between the prepared concentration values and PLS predicted concentration values, and that there was no evidence of bias within the 95 % confidence level. The PLS models showed excellent correlation in the prediction set ( R  = 0.999) and did not present systematic errors according to the ASTM E1655 standard. Therefore, the models presented excellent performance in quantifying soybean oil as an adulterant in B5 blends, in concentrations within the range 1.00–30.00 % (w/w). The proposed methodology showed itself to be efficient for quality control of B5 contaminated with vegetable oil.

Beschreibung: Triglyceride composition and fatty acid profiles of pomegranate seed oil were evaluated by newly developed methods in reverse-phase-high performance liquid chromatography (RP-HPLC) and gas chromatography (GC), respectively. Different compositions of the mobile phase (acetone and acetonitrile) and flow rates for the HPLC system were used to obtain better separation for accurate quantitative analysis. Triglycerides with conjugated fatty acids (CLnAs) were eluted in order of the polarity of their geometrical isomers (c, t, c 〈 t, t, c 〈 t, t, t). The dominant triglyceride was found to be PuPuPu (32.99 %) in pomegranate seed oil, followed by PuPuCa and PuCaCa containing punicic acid and catalpic acid with total triglyceridelevels of 27.72 and 10.11 %, respectively. For fatty acid composition analysis, triglyceride fractions were derivatized into their respective methylesters which were injected into gas chromatography-mass spectrometry (GC-MS) to identify and gas chromatography-flame ionization detector (GC-FID) to quantify the conjugated fatty acids of each fraction of triglycerides. Punicic acid was found to be dominant (76.57 %) followed by catalpic acid (6.47 %) and β-eleotearic acid (1.45 %). Pomegranate seed contained greater amounts of conjugated linolenic acids. These results showed that the present study provides more information about the composition of the triglyceride and fatty acid profiles of pomegranate seed oil compared to the reported studies. Therefore, the developed methods in this study can be used for the identification of the triglyceride and fatty acid composition for pomegranate seed oils and some such specials edible oils including CLnA isomers.

Beschreibung: Increasing the supply of biodiesel by defining and developing additional feedstocks is important to overcome the still limited amounts available of this alternative fuel. In this connection, the methyl esters of the seed oil of Gliricidia sepium were synthesized and the significant fuel-related properties were determined. The fatty acid profile was also determined with saturated fatty acids comprising slightly more than 35 %, 16.5 % palmitic, 14.5 % stearic, as well as lesser amounts of even longer-chain fatty acids. Linoleic acid is the most prominent acid at about 49 %. Corresponding to the high content of saturated fatty acid methyl esters, cold flow is the most problematic property as shown by a high cloud point of slightly 〉20 °C. Otherwise, the properties of G. sepium methyl esters are acceptable for biodiesel use when comparing them to specifications in biodiesel standards but the problematic cold flow properties would need to be observed. The 1 H- and 13 C-NMR spectra of G. sepium methyl esters are reported.

Beschreibung: Canolol-enriched extracts obtained from the extraction of fluidized bed treated canola meal with supercritical carbon dioxide were added to high-oleic canola oil in different concentrations (200, 500 and 750 mg/kg). After 30 h of deep-fat frying, oils fortified with canolol-enriched extracts showed a two to three times better frying performance in comparison to the commonly used antioxidants (TBHQ, 200 mg/kg; rosemary extract, 40 and 200 mg/kg) and a control without antioxidants with regards to the formation of di- and polymer triacylglycerols, total polar compounds, secondary degradation products (anisidine value) and the iodine value. The canolol-enriched extracts were also able to slow down the degradation of α- and γ-tocopherol during frying resulting in significant amounts of tocopherols after 30 h of frying in comparison to the other oils. The influence of the canolol-enriched extracts indicated strongly concentration-dependent performance. With increasing concentration of the extract, the thermal stability of the fortified oil was improved. The only disadvantage of the addition of the extracts was an increase in the initial acid value, but within the frying time, only oil fortified with 750 mg canolol-enriched extract/kg reached the limit given in different countries.

Beschreibung: To facilitate the analysis of castor ( Ricinus communis L.) seed fractions and germplasm for ricin content, we investigated the use of enzyme-linked immunosorbent assay (ELISA) methods to differentiate between ricin toxin and the related Ricinus communis agglutinin (RCA). Both proteins are based on a heterodimeric AB structure, with a common A chain. RCA comprises two dimers of A and B chains. Both proteins are found in the meal remaining after castor oil extraction and impede the commercial production of castor seed in the USA. We identified pairs of monoclonal antibodies (mAbs) that could distinguish between the structurally related proteins that share a common A chain. Antibody specificity was determined by ELISA and checked by immunoblotting. We found that mAb–mAb pairs afforded quantification of each castor protein, and that a mAb paired with a commercial polyclonal antibody provided detection of both with comparable sensitivity.

Beschreibung: Numerous derivatives of fatty acids (FA), including esters of methanol/3-hydroxymethylpyridine or dimethyloxazoline, are used for the analysis of FAs in biological specimens. Picolinyl derivatives are frequently prepared for structural determination by gas chromatography–mass spectrometry (GC-MS) since they provide characteristic fragments. The ester can be prepared by chemical methods-multistep methodologies or basic transesterification. Microbial lipases catalyze a number of transesterification reactions, and their catalytic activities are often stable at extreme conditions. Although these characteristic features may be useful in the application of typical FA structure analysis by picolinyl ester, detailed studies have not been reported. To address the problems, a simple and quantitative methodology for the synthesis of picolinyl esters from lipids has been developed. It involves the transesterification with Novozym 435 (Novozymes Biopharma US Inc., Franklinton, USA), resin-immobilized lipase from Candida antartica in toluene. Mild reaction conditions allow for complete derivatization of perilla seed oil in 30 min at 50 °C. The procedure was further studied with various TAGs and fatty wax from 17 plants. The optimized procedure was as follows; 1 mg lipid and 20 mg catalyst in 2 mL toluene at 50 °C for 1 h. Quantitative analysis of marker FAs was performed with the proposed method. The results coincided well with those from potassium t -butoxide-catalyzed reaction. The optimized method, however, was not applicable for the determination of some epoxy FAs, fatty wax, and parinaric acid.

Beschreibung: The proximate, physicochemical, and fatty acid compositions of seed oil extracted from khat ( Catha edulis ) were determined. The oil, moisture, crude protein, crude fiber, crude carbohydrate, and ash content in seeds were 35.54, 6.63, 24, 1.01, 30.4 %, and 1.32 g/100 g DW respectively. The free fatty acids, peroxide value, saponification value, and iodine value were 2.98 %, 12.65 meq O 2 /kg, 190.60 mg KOH/g, and 145 g/100 g oil, respectively. Linolenic acid (C 18:3 , 50.80 %) and oleic (C 18:1 , 16.96 %) along with palmitic acid (C 16:0 , 14.60 %) were the dominant fatty acids. The seed oil of khat can be used in industry for the preparation of liquid soaps and shampoos. Furthermore, high levels of unsaturated fatty acids make it an important source of nutrition especially as an animal product substitute for omega-3 fatty acids owing to the high content of linolenic acid.

Beschreibung: The ozonolysis of unsaturated lipids is a process that has been used to generate aldehydes, acids, alcohols, and other biobased chemical intermediates. Reported here is a method that can be used to measure the formation of nonanal and oleic acid during the ozonolysis of unsaturated vegetable oil fatty acids or their methyl esters to indicate the extent of the ozonolysis reaction. Derivatization was performed using boron trifluoride in methanol solution to transform nonanal and oleic acid into nonanal dimethyl acetal and oleic acid methyl ester, respectively. Undecanal and 10-heptadecenoic acid were used as internal standards and separation was performed using gas chromatography coupled with a flame ionization detector. The method was validated by performing a standard addition procedure in which nonanal or oleic acid standards were spiked into samples collected during the ozonolysis of oleic acid or canola oil fatty acid methyl ester (FAME). Linear regression results indicated that the measured nonanal and oleic acid are in good agreement with the actual amounts of nonanal and oleic acid added to the sample with at least 98 % recovery. The application of the method was demonstrated by the successful measurement of nonanal and oleic acid formed throughout the ozonolysis process for high oleic canola oil FAME.