ALBERT

Notes: Tuber disks of five potato cultivars, each compatible to the fungus race used, were treated with cell-free homogenate or lipophilic material obtained from the mycelial mat of Phytophthora infestans. On the effect of treatments, the various cultivars reacted in different manners as regards tissue necrotization and accumulation of phytoalexins rishitin, lubimin and phytuberin. No correlation was found between the extent of tissue necrosis and the level of phytoalexins. Each potato cultivar had a capacity for producing sesquiterpene phytoalexins even if the visible hypersensitive response (tissue necrosis) did not occur. It was concluded that there are compounds of pathogenic origin that induce phytoalexin accumulation as well as necrotization in plant tissues. The expression of necrotization mainly depends on different sensitivity of potato cultivars to treatments. The rate of phytoalexin accumulation would represent a potential for general resistance.

Notes: Fumigants are used to prevent pest infestations in food and other stored commodities. The quality of the commodity may be affected by fumigant treatment in several ways. Residues of unchanged fumigant may remain in the commodity. Reaction of the individual chemical components of the commodity with the fumigant may alter its chemical or physical properties, thus resulting in changes in flavor, taste, odor, nutritional value or processing qualities. Methyl bromide, ethylene dibromide, ethylene dichloride, carbon tetrachloride, phosphine and ethylene oxide are the major fumigants used for treatment of grains, vegetables and fruits. Their effects on food quality and the significance of residues in treated commodities are reviewed.

Notes: A chemically defined synthetic medium was developed on which Phytophthora infestans (Mont.) de Bary strain 1.2.4 grew extensively. The medium consisted of: 90.0 g maltose; 20.0 g L-proline; 20.0 g DL-alanine; 1.0 g KNO3; 0.50 g KH2PO4; 0.25 g MgSO4 7H2O; and 1.0 mg thiamin per liter of distilled water. The average level of growth on this medium was 0.5864 g dry weight mycelium per 50 ml medium. The glycoalkaloids, solanidine and solanine, were produced by P. infestans in this medium at an average concentration of 0.8518 mg total glycoalkaloids per 25 ml medium with a range of 0.0 to 5.9 mg per 25 ml. No glycoalkaloid production was detected when the level of growth of the fungus was below 0.35 g dry weight mycelium/50 ml medium. Glycoalkaloids were synthesized by 5 of 10 cultures grown on chick pea medium and by none of 10 cultures grown on rye seed medium.

Notes: Enterotoxin A and thermonuclease were produced by Staphylococcus aureus cell populations in all growth phases. Synthesis of entero-toxin was more rapid than that of thermonuclease early in the exponential phase, whereas later in the exponential phase the thermonuclease synthesis was more rapid than that of enterotoxin. The optimum temperature for enterotoxin production was 42°C, while that for thermonuclease production was in the range 27–33°C. Small amounts of enterotoxin and thermonuclease were released at temperatures up to 45°C.During heat treatment of staphylococcal cells, enterotoxin production was not observed at temperatures in excess of those permitting growth, although small amounts of thermonuclease were produced. Intracellular enterotoxin was not detected after disintegration of cells under pressure at –30°C. Enterotoxin at detectable concentration, was not bound to the cell membranes. All the results obtained indicate that the synthesis of enterotoxin by S. aureus is intimately associated with cell growth.

Notes: The analysis of several breakfast cereals has shown that methyl chloroform (MCF, 1,1,1-Trichloroethane), a solvent found to be present in the adhesive of the outer box, can migrate from the adhesive through the box and the waxed liner into the cereal. The levels of MCF in the adhesive, the outer box, the waxed liner and the cereal were found to range from 0 to 2.3%, 0 to 19.4 ppm, 0 to 4.8 ppm, and 0 to 0.40 ppm, respectively, in 11 breakfast cereals. The MCF residues were determined using a closed system-vacuum distillation gas chromatographic technique with both electron capture and electrolytic conductivity detection. The results were confirmed by high resolution mass spectrometry.

Notes: Swine were fed a diet containing hexachlorobenzene (HCB) in order to generate contaminated pork which was subsequently cooked and fed to female cats. Feeding the fresh weight equivalent of 50 g cooked pork/day/cat (1 〈 mg HCB/kg/day) caused marginal weight loss. Oral dosing with 10 mg/kg/day purified HCB resulted in significant weight loss, mild anemia, neutropenia and hepatomegaly. Using the residue of HCB accumulating in the cat adipose tissue as the criterion, the low doses in the pork were absorbed and retained about five times more effectively than the larger oral bolus.

Notes: Book review in this Article Food Microbiology: Public Health and Spoilage Aspects, M. P. deFigueiredo and D. F. Splittstoesser.

Notes: The kinetics of distribution of ochratoxin A (OA) in chicken tissues was studied. Day-old chicks were fed a starter diet alone or containing 1 ppm OA. After 5 weeks, all chicks were intubated with 50 μg 3H-OA per chick. The highest level of radioactivity was found in kidney and liver 8 hr after intubation. Peak levels of OA in kidney, liver and breast were found to be 12, 4, and 0.2 ppb, respectively. Over 90% of the radioactivity was eliminated 48 hr after intubation. Moreover, when laying hens were fed a diet containing 0.5 or 5.0 ppm of OA for 2 weeks, the highest levels of OA were found in the kidney (124 ppb) and liver (80 ppb) also. Levels of OA in breast, leg and eggs of laying hens were found to be 8, 7, and 2.8 ppb, respectively.

Notes: Previous epidemiological studies of nasopharyngeal carcinoma suggest that traditional food items, particularly salted fish, consumed by southern Chinese may play a role in the cause of the high frequency of the disease among them. We report here the results of an analysis by combined gas chromatography and high resolution mass spectrometry of six types of salted fish and ten other items of traditional southern Chinese salted food products for the presence of volatile nitrosamines. Only N-nitroso-dimethylamine (NDMA) was detected in some of the samples of salted fish examined. No volatile nitrosamine other than those added as internal standards was detected in any of the others.

Notes: The effects of pyruvate, succinate, citrate, alpha-keto glutarate, fumarate, malate, lactate, and glycerol supplementation (0.5, 1.0, and 2.0 g/100 ml) on aflatoxin production by A. parasiticus NRRL 2999 were examined in synthetic and semi-synthetic media. Glycerol, lactate, and the 0.5 g/100 ml level of pyruvate stimulated production in the synthetic medium. At the 2.0 g/100 ml level, pyruvate, citrate, alpha-keto glutarate, fumarate, and malate inhibited aflatoxin accumulation in both media. With the exception of glycerol, all supplements stimulated sporulation and elevated the pH of the cultures.

Notes: Top and bottom round steaks inoculated with Yersinia enterocolitica were stored vacuum packaged and in polyvinyl chloride (PVC) films at 1, 2.5 and 5°C for 21–35 days. Y. enterocolitica and total aerobic plate counts of steaks were consistently higher in the more oxygen permeable film (PVC) than in the vacuum packages. The microbial flora of the vacuum packaged steaks at the end of the storage period (21–35 days) consisted, in addition to Y. enterocolitica, primarily of Lactobacillus spp., that of the steaks stored in PVC of Pseudomonas spp.

Notes: Growth, sporulation and enterotoxin formation in various foods inoculated with a Clostridium perfringens type A enterotoxin-producing strain were studied. Good vegetative growth, 107–108 cells/g, was obtained after 4 hr of anaerobic growth and remained almost the same throughout the 20–24 hr observation in most of the foods. A gradual increase in spore count to the level of 104–105/g was observed with an increase in the incubation time. Enterotoxin was detected in moist cooked chuck roast, ground beef and turkey as well as in moist cooked and dry roasted chicken at levels up to 0.125μg/g. The earliest time at which enterotoxin was detected was after 10 hr of anaerobic growth in moist cooked turkey at 37°C. Although growth and some sporulation occurred, enterotoxin was not detected in dry roasted beef or turkey with or without gravy, or in moist cooked pork or lamb. Poor growth and sporulation also were obtained with chicken broth, chicken gravy and beef gravy. In moist cooked turkey that had been temperature abused for 6 hr at 37°C, held cold for 15 hr and reheated to 37°C, toxin could be detected after only 5 hr of holding at 37°C. The ability of certain foods to support sporulation and enterotoxin formation indicates that such preformed enterotoxin may contribute to early onset of symptoms in some cases of C. perfringens food poisoning.

Notes: Butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) were applied to six strains of toxigenic and six strains of non-toxigenic Aspergillus flavus in a method similar to antibiotic susceptibility testing. The cultures were examined for growth inhibition, spore formation, pigmentation, and aflatoxin production. BHA (0.005–0.020 g per plate) had an inhibitory effect on growth and toxigenesis of the test organisms, while BHT (0.005–0.020 g per plate) had no visible inhibitory effects. Sporulation of the cultures had no direct relationship with toxigenesis in the presence of BHA. However, pigmentation of the mycelium is directly related to the intensity of fluorescence of the culture under UV. Heating of BHA did not reduce the inhibitory effect of the compound on A. flavus.

Notes: The molecular sizes of Clostridium botulinum type A, B, E, and F toxins produced in string beans, mushrooms, tuna fish and pork were determined to provide an explanation for the high botulogenic properties of vegetables. Type A and B organisms produced the orally more toxic 16S and 19S molecular-sized toxins in vegetables, whereas they produced the orally less toxic 12S and only rarely some 16S toxin in tuna fish and pork. Type E and F organisms produced only 12S toxin in any food or culture medium, but addition of glucose seemed essential for appreciable toxin production. It appeared that the molecular sizes of type A and B toxins transform depending upon the content of iron and manganese salts in foods.

Notes: A solid-phase radioimmunoassay (RIA) for aflatoxin B1 (afla B1) was developed. This method involved the incubation of afla B1, both labelled and unlabelled, with immunoglobulin (IgG)-sepharose gel which was prepared by conjugation of the IgG highly specific to afla B1 with CNBr-activated sepharose gel, followed by a filtration step. The binding capacity was determined by counting the radioactivity in the filtrate. Studies with different afla B1 analogues revealed that the IgG-gel bound most effectively with B1. Binding of afla B2, G1, G2, and aflatoxicol to the IgG-gel was less effective in comparison with the IgG before coupling. Between 0.5–5.0 ng per assay, the displacement of radioactivity from the gel was directly proportional to the amount of afla B1 present. Using a simple extraction procedure without clean-up step, the recovery yields for afla B1 in the contaminated corn or wheat at levels of 5 ppb or above were above 60%.

Notes: For more than a generation, the United States has carried out a donation program to relieve world food shortages. Processed high-protein blended food products, enriched with vitamins and minerals, were developed to supplement the diets of hungry children. Corn-based foods for food aid programs were prepared by combining yellow corn with soybeans and other protein supplements. Storage stability, a critical factor for worldwide shipment, was investigated as a function of processing, formulation, packaging and distribution under various climatic conditions. Processing yellow corn and other components includes dry milling, which may or may not be followed by some form of cooking. Cooking must be carefully controlled to inactivate hydrolytic and oxidative enzymes that could cause deterioration. Overcooking must be avoided because it may also reduce storage stability. Adequate storage stability of corn-based foods depends upon such other factors as removal of germ or adequate processing of the germ and other protein supplements, use of nonreducing sweeteners and the control of moisture. Storage stability can be predicted from product time-temperature studies.

Notes: The present industrial production of tortilla flour is virtually an extrapolation of the home process, involving a cooking and drying operation as the main energy expenditures and costs. The possibility of preparing an acceptable instant tortilla flour, by means of other technologies, was therefore explored. Whole raw corn flour was mixed with water (ratio of 3:1) and lime (0.3% of the corn flour weight). This dough was then passed through a double-drum drier. With a drum opening of 0.003 in. (7.62 × 10−3cm), it was found that the use of an internal pressure of either 15, 20 or 25 psig (93, 99 and 104°C surface temperature, respectively) at 2, 3 or 4 rpm, produced an instant tortilla flour with physicochemical and organoleptic characteristics identical (P 〈 0.05) to those of the reference sample prepared by hand. In contrast, commercial samples of a similar product proved to be different (P 〈 0.05) from the standard and from the product obtained with the drum drier, both from the physicochemical and organoleptic standpoints. Economically, the new process indicated that it was not only feasible, but that it also can allow for the supplementation of tortilla at the industrial level.

Notes: A desirable method which ensures the long storage of cooked rice was studied using texturometer and gas measurements. Polished rice was immersed in 0.5% acetic acid for 10 min, then cooked in the same solution. The cooked rice was made into discs and kept in air-tight film bags at 30°C for about half a month. These discs had good textural characteristics even after the long storage period. Discs which were also prepared by adding a small volume of acetic acid (4.2%) to the cooked rice after the initial treatment, these exhibited better textural qualities after storage. These treatments considerably inhibited browning and retrogradation of the starch as well as inhibiting the growth of bacteria and fungi during storage.

Notes: Soybean curds are very perishable. The shelf-life of fresh soybean curds varied with storage temperatures. In-package microwave heating treatment of fresh soybean curds effectively extended shelf-life. Storage at 4.5°C, soybean curds pretreated with microwave heating to 65°, 80° and 95°C have shelf-life of 16, 21 and 27 days, respectively, compared to 7 days in control. Decrease in pH, increase in titratable acidity, and viable counts in the soaking water accompanied decreases in quality of soybean curds.

Notes: The rate of lipid oxidation during storage of raw peanuts is at a minumum in comparison with that after roasting. The effect of heat processing on the activities of several enzymes was studied in relation to lipid stability in Spanish peanuts. Lipoxygenase was not found in whole shelled peanuts after steaming for 2 min at 100°C, and very little peroxidase activity could be detected after 30 min. A heat-labile factor which destroys hydroperoxides and prevents their accumulation was inhibited by KCN and inactivated in whole shelled peanuts by steaming for 30 min at 100°C. The rate of hydroperoxide formation in stored whole shelled peanuts first increased and then decreased with the time of steaming prior to storage. Stability characteristics of full-fat peanut flakes were shown to be dependent upon the conditions of heat treatment of peanuts prior to drum drying.

Notes: Several varieties of fresh peaches at three maturity levels were subjected to bulk compression using a specially constructed apparatus. The texture notes of hardness, elasticity, graininess, and dry-moist mouthfeel were evaluated by a sensory panel. In an effort to determine if bulk compression may be used to evaluate texture in peaches a correlation analysis was performed on the instrumental and sensory data. It was found that hardness and elasticity were positively correlated with the bulk modulus and that the mouthfeel score showed a negative correlation with the modulus value.

Notes: Comparative studies were made of lactose and sucrose precipitation from aqueous solutions by the formation of carbohydrate-alkaline earth hydroxide complexes. Lactose can be recovered in the precipitate using lower concentrations of calcium hydroxide than can sucrose. Insoluble complexes with barium were not produced with lactose under conditions that yielded complexes with sucrose. Also studied was the influence of the concentration of reagents, the alkaline-earth metal employed, and the addition of organic solvents. The ratio of Ca(OH)2/lactose in the precipitate depended on the ratio of reactants in the original solution rather than on the absolute concentrations of Ca(OH)2 and lactose. Addition of organic solvents increased the recovery of lactose. Acetone was more effective than ethanol, methanol being the least effective.

Notes: Frankfurters were made by standard commercial practices except for the smoke treatment which involved four different methods: solid smoke-aerosol, liquid smoke-aerosol, liquid smoke-external dip, and liquid smoke-internal mix. For control purposes, frankfurters were prepared without any smoke treatment. All frankfurters were packaged and stored at 5°C with samples removed for analyses weekly for 3 wk. Method of smoke application did affect the processed weight of the frankfurters. Liquid smoke-aerosol treatment produced the heaviest franks; the liquid smoke-internal mix application produced franks lighter in weight than the other treatments including the nonsmoked control. Smoke treatment had no significant effect on the fat or total volatile nitrogen (expressed on a fat-free basis) content of the franks. However, it did affect the amounts of moisture, phenol, FFA and TVN as well as the pH and TBA values. The use of the liquid smoke-external dip significantly lowered the nitrite content of the franks when compared to all other treatments which were not different from each other. As the phenol content increased, pH decreased. Generally, storage had no effect on the frankfurter properties evaluated in these studies. However, pH was seen to drop then rise again whereas the amount of FFAs rose then fell during the 3-wk period.

Notes: Pieces of beef, pork and poultry were immersed for 2, 6 and 24 hr in 100 times their weight of water containing 200 ppm chlorine labelled with 36C1. Within 2 hr over 50% of the chlorine had reacted with the meat. Most of the products of chlorination were water-soluble and had leached into the water but small amounts of chlorinated lipids and water-soluble chlorinated compounds were found in the meat. These ranged from 2–3% of the total 36C1 present at 2 hr to 6–8% at 24 hr. Meat treated with chlorinated water was found to increase much more in weight than meat treated with unchlorinated water. Chicken skin was found to absorb more water than lean or fat and increased in weight by 130% after 2 hr in chlorinated water.

Notes: Muscles from 20 U.S. Good carcasses were passed through a blade tenderizer one (IX), two (2X) or three (3X) times to determine effects on cooking and palatability characteristics. Psoas major (OX, IX) and semitendinosus (OX, IX, 2X, 3X) muscles were studied. Blade tenderization had little or no effect on thawing loss, cooking loss, cooking time or degree of doneness for steaks from either muscle. Blade tenderization (IX) decreased (P 〈 0.05) shear force requirements and amounts of organoleptically detectable connective tissue and increased (P 〈 0.05) ratings for tenderness for cooked steaks from both muscles. Shear force data suggested that semitendinosus can be made as tender as psoas major by blade tenderization (2X), but organoleptic data did not support such a conclusion, suggesting that sensory panel members considered factors other than or in addition to resistance to shear in assessing relative tenderness. Blade tenderization enhanced the tenderness of two muscles which differ greatly in connective tissue content. Absolute response to blade tenderization (IX) was greater for semitendinosus (by 0.3 kg, shear force; by 0.5 rating scale units, connective tissue amount; and by 0.2 rating scale units, tenderness) than for psoas major. Data suggest that blade tenderization disrupts connective tissue, but not to the extent that would allow blade tenderized muscles high in connective tissue to be used interchangeably with untreated muscles of low connective tissue content.

Notes: Textural characteristics of fabricated breaded shrimp are influenced by composition and processing parameters. The contributions (to final cooked shrimp texture) of geographic source, protein and moisture content of shrimp, comminuting and mixing method used, and matrix agent amount and composition were investigated. The Universal Penetrometer was used to determine consistency of comminuted shrimp-matrix agent mixtures and the use of these data to predict optimum mechanical extruder performance was evaluated. The effect of matrix agent composition and level on extruder performance was also investigated. Protein content of shrimp varies with geographic origin; as protein level increases, Instron springiness values on cooked patties also increase. Choice of comminuting-mixing method influences final Instron TPA values. Highest springiness values were obtained using a silent cutter technique which minimized particulate retention and probably maximized extracted myofibrillar protein in the final comminuted shrimp-matrix agent mixture. Matrix agent composition and choice play an important role in extruder performance and final shape texture; as matrix agent level was increased to 12%, the temperature had to be increased to 4.4°C in order to insure optimum consistency and plastic flow. Highest Instron springiness values for cooked shrimp patties were obtained using isolated soy protein (ISP) and the lowest values were obtained using a starch-gum base matrix agent.

Notes: Some naturally occurring and synthetic phenolic antioxidants have been evaluated in a dry model system simulating the exposure of lipids in freeze-dried membranes of whole tissue foods. The system is a linoleic acid monolayer on activated silica gel autoxidized at 80°C in dry air. The system is dry and porous and the demonstrated monolayer adsorption and restricted translational mobility of the lipid present a plausible model of freeze-dried membrane characteristics. Although relative effectiveness of the common antioxidants in this system has some similarities to the reported order in other dry systems, there are notable exceptions. For example, butylated hydroxyanisole is by far the most effective antioxidant in the silica system whereas it is reported to be much less effective than propyl gallate in bulk oils and some other dry systems. Thus, special conditions appear to modify antioxidant effectiveness in the lipid monolayer on silica.

Notes: The activity of aqueous extracts from red pepper fruits (Capsicum annuum L.) toward the oxidation of carotene presence of linoleate was measured by a colorimetric method. Highest activities were achieved by using as extractant distilled water or Tris buffer at pH 7.0, whereas solubilization of carotene-bleaching factors by Triton X-100 or preparation of acetone powder from pepper fruit extracts resulted in losses in carotene-oxidizing activity. After dialysis, ammonium sulfate precipitation and chromatographic purification on Ecteola and Sepharose 6-B, a proteinous carotene-oxidizing fraction was obtained which exhibited properties similar to those of a peroxidase, i.e., high specific activity toward guaiacol oxidation in the presence of hydrogen peroxide, precipitation with ammonium sulfate between 60 and 95% saturation, change in spectral absorbance upon addition of cyanide, inhibition of carotene bleaching activity by KCN, and typical changes in carotene-bleaching activity with pH and protein concentration.

Notes: Three varieties of soybean (Bragg, Punjab-1 and Lee) were chemically evaluated for their protein quality from the amino acid data, solubility classes of proteins, chemical score, essential amino acid index, requirement index and electrophoretic pattern of proteins. Cotyledon, the major component of seed, accounted for about 93% of tryptophan and methionine of the whole seed. Glycinin as the predominant fraction of soy protein (about 63% of total protein) contained 73% and 71% of the amount of methionine and tryptophan of the whole seed, respectively, but was deficient in methionine. Albumin, constituting about 12% of total soy protein, was also deficient in methionine but was quite rich in tryptophan. Prolamine fraction of soy protein was rich in methionine and tryptophan. On the other hand, glutelin was the poorest in these amino acids. Soy protein contained a balanced amino acid pattern with the exception of methionine which was found to be the main limiting amino acid. The electrophoretic pattern of albumin fraction of Punjab-1 and Bragg differed from that of Lee while there were no varietal differences in the pattern of whole seed proteins and glycinin. Punjab-1 appeared to be better in its protein quality based on its higher values of chemical score, essential amino acid index and requirement index. The present investigation has revealed that chemical evaluation is comparable to biological evaluation and can serve as a good index in the assessment of protein quality of food grain.

Notes: The total and free amino acids of authentic vanilla extracts of Madagascar, Tahiti, Comores, Mexican and Java beans were determined by GLC. Ten samples of single strength Madagascar vanilla extracts gave free amino acids with a mean value, standard deviation and coefficient of variation of 73.3 ppm, 19.88 ppm, and 27.12%, respectively; this compares to the total amino acids with a mean value, standard deviation, and coefficient of variation of 295.71 ppm, 31.10 ppm, and 10.52%, respectively. The ratio of free amino acids to total amino acids for Madagascar single strength vanilla extracts gave a mean, standard deviation, and a coefficient of variation of 0.25, 0.64 and 2.58%, respectively. In addition, the vanillin, nitrogen, phosphate, and potassium were determined by spectrophotometric procedures for the above mentioned beans.

Notes: The volatile constituents of cooked beets (Beta vulgaris), obtained by distillation-extraction of the beets, were separated by gas chromatography and subjected to infrared and mass spectral analysis and 17 components were identified. A unique feature of this vegetable is the high concentration of 4-methylpyridine and pyridine, which constitute about 60% of the total volatiles. Other components present at greater than 1% level include dimethyl sulfide, isovaleraldehyde, ethanol, isopentanol and furfural. The occurrence of geosmin and 2-methoxy-3-secbutylpyrazine were confirmed; the low flavor thresholds of these compounds suggest they play a role in beet flavor.

Notes: Spores of Bacillus cereus NRRL 3476 and of Clostridium sporogenes ATCC 7995 (PA 3679) were inoculated onto stainless steel surfaces. After the spores had dried on the surface, the surface and spores were exposed to 9.2% hydrogen peroxide for sufficient time to achieve a two-log reduction in the number of viable cells. The number of surviving spores was determined by pouring the agar media directly onto the stainless steel surface and incubating for appropriate lengths of time. When spores of B. cereus or PA 3679 were treated with hydrogen peroxide, their recovery was enhanced if the pH of the recovery medium was adjusted to pH 7.3. Further increase in recovery occurred if 0.5% soluble starch was added to the recovery medium for B. cereus and if 5 μM of glutathione/ml was added to the recovery medium of PA 3679. Temperatures of incubation in the range of 28-36°C had no influence on recovery.

Notes: An electroimmunoassay was developed for quantitating whey protein concentrates incorporated into frankfurters. The simple, precise method has potential for application to a variety of other whey fortified foods. Frankfurters containing 3–7% whey protein concentrate were homogenized in 7M urea and the extract was electrophoresed on agarose plates containing antiserum to α–lactalbumin. Quantitation was obtained by measuring and comparing migration distances for the extracts and control whey concentrates; recoveries ranged from 96–105%. The concentrations of β-lactoglobulin and α–lactalbumin in milk and whey protein fractions were determined in buffer solutions using the respective antisera.

Notes: Iron content and bioavailability of mechanically-deboned (MD) and hand-deboned (HD) beef was investigated. Shank and plate bones with residual meat from utility grade animals were treated by both deboning processes. Iron content of MD meats was higher than HD meats. Rats were made anemic and fed one of the following diets: basal, basal + FeSO4, MD shank, HD shank, MD plate or HD plate. Hemoglobin regeneration served as the basis for measuring iron utilization. The iron from FeSO4 was most efficiently utilized. Iron from HD shank and HD plate were better utilized than iron from MD shank and MD plate.

Notes: Evidence has been presented to show that myofibrillar fragmentation is the principal cause of the tenderness of poultry meat. Changes in actinmyosin interaction seems to play some role during frozen storage at −20°C. The changes in shear force and myofibrillar fragmentation of hen pectoral muscle during storage at 4°C and −20°C were studied, comparatively. The shear force values of postrigor muscle stored at 4°C and those of frozen muscle were about half of the fresh muscle values. Myofibrillar fragmentation in samples stored at 4°C was complete on 3rd day postmortem; whereas it proceeded gradually during storage at −20°C. Myosin heavy chain was degraded in frozen muscle samples, which in turn affected myofibrillar ATPase activity. 27,000 and 30,000 dalton proteins, possibly the degradation products of troponin, appeared in muscle samples stored both at 4°C and −20°C.

Notes: A sensitive gas chromatographic method has been developed for betanitropropionic acid (BNP), a compound produced by certain molds. The method is based on extraction, isolation and derivatization of the compound to yield its pentafluorobenzyl derivative and determination by electron affinity gas chromatogiaphy. The structure of the derivative was verified by mass spectrometry. The method has been applied to the determination of BNP in mold filtrates and cheeses with a limit of detection of about 1 and 3 ppm, respectively.

Notes: With the aid of viscometry, turbidimetry, paper electrophoresis, and electron microscopy, more insight into the gelation of yolk upon freezing and thawing has been gained. The pseudoplastic nature of yolk and plasma was found to be enhanced by freezing for a few hr at −14°C. With a rise in temperature from 10 to 50°C, the apparent viscosities of frozen-thawed yolk and plasma decreased considerably, whereas little viscosity change was obtained with unfrozen samples. During the freezing process, low-density lipoproteins (LDL) of the yolk presumably interacted through at least some heat-labile bonds (perhaps H bonds) to produce a more viscous, pseudoplastic mass. The results of paper electrophoresis of unfrozen and frozen (−10 and −14°C)-thawed yolk and plasma suggested that LDL aggregates were formed during frozen storage. Turbidity experiments supported this supposition. As in the case of yolk, the rate of viscosity change for plasma increased with a drop in the frozen storage temperature from −10 to −14°C. The loss of LDL mobility during paper electrophoresis was also related to the storage temperature. The higher LDL micelle content and soluble salt concentration may account for this temperature effect. The gelation rate for plasma increased progressively as the granule content was raised to 20% of the total solids of the dispersion. Possibly the granule's of yolk are disrupted during freezing by a high concentration of soluble salts in the unfrozen phase and, thereafter, LDL micelles are liberated. In electron micrographs of frozen-thawed yolk, a large lipid mass and some fluffy electron-dense masses, smaller than the granules in native yolk were observed. These fluffy masses are presumably residues of completely disrupted granules.

Notes: Addition of up to 50% of oven-dried white bread in diets had no effect on utilization of ferrous sulfate iron by rats that were previously iron deficient. Diets were adequate in protein and all other nutrients, except iron, and bread was added only at the expense of carbohydrate. The parameters of response measured were hemoglobin, packed cell volume and red blood cell count. In diets containing a high proportion of protein from wheat, the low nutritional value of this protein may contribute to poor iron absorption but white bread itself appears not be detrimental to utilization of the mineral.

Notes: Factors affecting growth and lipase production by Penicillium chrysogenum were studied. The optimum conditions for lipase production by the mold were 30°C at pH 6.0. In shake cultures, lipase production was enhanced by 70%. Amongst several carbohydrates that were examined, maximum lipase production occurred in medium containing glucose, followed by maltose, mannitol, galactose, sucrose, lactose and fructose in the decreasing order. Out of different nitrogen sources peptone proved most stimulatory.

Notes: Fresh pork shoulders were boned and ground through a 12.7 mm plate, packed in 1-kg packages, frozen at −28.9°C and stored at −17.8°C for 2 wk. The frozen pork samples were thawed for 24 hr at 3°C, then blended with a curing mixture consisting of 6 parts of NaCl and 1 part sugar at a rate of 47.5g/kg of meat with erythorbate and NaNO2 added to give levels of 0,183, 366 or 550 ppm of erythorbate and 0, 50,100, 150 or 200 ppm nitrite in the meat. The pork was then inoculated at the rate of 11 spores of Clostridium perfringens (UK92)/g, packed in quart jars (500/g jar) and cured for 2 wk at 1-4°C followed by 2 wk salt equalization at 12.8°C. Enumeration for C. perfringens began at this time and continued on alternate weeks during the 6-wk aging period. Recovery of C. perfringens spores was significantly reduced by NaNO2. After 4 wk, 80% of the inoculated spores were recovered from samples with no added nitrite while only about one-third of the spores were recovered from samples with the lowest level of NaNO2. Higher levels of nitrite and increased aging time reduced the number of spores recovered. At 10 wk, recovery was 38.0, 12.0, 5.4, 3.6 and 0.9% of inoculated spores, respectively, for 0, 50, 100, 150 and 200 ppm NaNO2. Sodium erythorbate had no significant effect on recovery of spores. Nitrite levels in the meat decreased rapidly with less than 60% of initial levels remaining after 24 hr. Only about 10% of initial concentrations were present after 4 wk. Results generally were similar for survival of C. perfringens spores and for nitrite losses when ground pork samples were dry-cured in stockinettes and aged for the same time and at the same temperature as those cured in jars.

Notes: The individual myofibrillar proteins, myosin and actin, were digested with crude papain (1:125 w/w for 0–3 min). The sodium dodecyl sulfate electrophoretic patterns and the rate of proteolytic hydrolysis were observed. Actomyosin, natural actomyosin and both contracted and uncontracted glycerinated myofibrils were also studied. It was found that the gel pattern of the actin proteolytic digestion suggested that two populations of actin exist; that although actin had the highest rate of hydrolysis in the pH stat, the gels suggested only a very limited proteolysis; that actomyosin is less rapidly digested than myosin; and that the proteins of the myofibrils, especially when contracted, are rapidly cleaved.

Notes: Ground beef with less than 2% added glucose showed typical spoilage characteristics by gram-negative psychrophiles during refrigerated storage. In samples containing 2–10% glucose, acids produced at the expense of the carbohydrate lowered the meat pH from 5.8 to 5.0–5.2. This low pH persisted in the meat until all glucose was depleted. During this period growth of the predominant nonpigmented Pseudomonas organisms was hindered, and no spoilage characteristics such as slime and off-odors were observed. When the glucose disappeared the meat pH started to rise. Incipient spoilage (off-odors and tackiness) became apparent when a pH value of 6.0 was exceeded. Lactobacilli counts were slightly higher in glucose-treated meat than in the control, but no bacterial shift was observed. Instead, the added glucose caused a shift in nutrient utilization by the spoilage microflora. Normally these bacteria attack the nitrogenous compounds in meat, resulting in production of alkaline by-products and elevated meat pH. In the presence of glucose, the same microorganisms utilized the carbohydrate preferential to other compounds in the meat. The oxidatively formed acids lowered the meat pH, affected the growth rate of the spoilage bacteria and hence retarded spoilage. The addition of 2% glucose to ground beef prolonged its average shelf life at refrigerated temperatures from 5 days to 8–10 days.

Notes: This investigation was undertaken to determine the ultrastructural changes in porcine muscle due to autolysis and their relationship to muscle fiber type. The red and white portions of aseptic porcine semitendinosus muscle were sliced, placed in sterile petri dishes, and stored at 10°C. Samples were taken periodically for pH measurements, bacterial counts and electron microscopic examination. No bacterial growth or significant pH changes were observed in the experimental tissues. White fibers appeared to be slightly more labile to autolysis than red fibers. However, the ultrastructural changes occurred in the same sequence for both fiber types. Mitochondria underwent cristae aggregation with a subsequent loss of cristae material. Nuceli were found to progressively shrink in size during storage with a concomitant concentration of the chromatin material. The I-band was the area of the myofibril most susceptible to autolytic breakdown and vesicular structures were observed in all areas of myofibrillar degradation.

Notes: The particulate matter of fresh, infertile egg yolk was studied using transmission electron microscopy. Granules in electron micrographs appeared to be composed of electron-dense subunits. Treatment of granules with 0.34M NaCl removed a considerable amount of matrix particles, and, as a result, subunits each consisting of a large globule overlaid with protein strands having attached electron-dense micro-particles, were observed. The structure of the granules was disrupted completely by 1.71M NaCl treatment. Upon ultracentrifugation of granules in 1.71M NaCl, five fractions (two floating and three sedimenting) were formed. The uppermost floating fraction, a semisolid pellicle, was made up of small and large globules with diameters ranging between 30–100 nm. The subpellicle floating fraction consisted of only small globules with diameters about 27 nm and numerous myelin figures. The three sedimenting fractions appeared to be made up of protein strands with attached micro-particles (presumably lipovitellins). The plasma was made up predominantly of small globules (LDL micelles) which had mottled surfaces but some myelin figures were also present. The diameters of the globules ranged between about 13–50 nm and the median diameter was about 23 nm. Small electron-dense particles, designated as ultraparticles, were noted on the surfaces of LDL micelles of plasma, These ultraparticles were released from the LDL surfaces when plasma was treated with pepsin. ultraparticles were also noted on surfaces of globules in granules.

Notes: Removal of gossypol from cottonseed meal and fermentable sugars from soybean meal by butanol-HCl solution was tested. Acidic butanol treatment yields low gossypol cottonseed protein concentrates and low oligosaccharides soy protein concentrates, respectively. This procedure does not appreciably alter proteins, as it is shown by the comparison of electrophoretic patterns of albumins and globulins extracted from meal and corresponding protein concentrates.

Notes: Aflatoxins B1 and G1, penicillic acid and patulin were each added to Swiss cheese, bologna and cooked cornmeal. The samples were stored at 5°C for 15 min and 3, 12, 24, 48, 120 and 168 hr before extraction and recovery of the added toxins. Aflatoxins B1 and G1 were stable in the foods during the entire storage period. Patulin and penicillic acid, on the other hand, were undetectable in bologna after 12 and 48 hr storage, respectively. In Swiss cheese, after 168 hr of storage at 5°C, 8% of the original penicillic acid remained. With cooked cornmeal, about 80% of the patulin and peniciuic acid were detected after 168 hr of storage at 5°C. Growth and experimental toxin production on Swiss cheese, Mozzarella cheese, bologna, bacon, cooked cornmeal, and English muffins were studied by using known toxinogenic strains of Aspergillus flavis, Penicillium patulum and a Penicillium sp. incubated at 5, 12 and 25°C for 6, 4 and 2 wk respectively. No growth of A. flaws or aflatoxin production was observed at 5 and 12°C on any substrate, but at 25°C, growth and aflatoxin production occurred on Swiss cheese, bologna, cooked cornmeal, Mozzarella cheese and bacon. Patulin and penicillic acid were produced in cooked cornmeal at all three temperatures. No patulin or penicillic acid was found in the other food substrates, except for a small amount of penicillic acid in one of the English muffin samples at 5°C, even though the molds grew extensively on all substrates at all three temperatures.

Notes: Protein fibril-formation was lost as a result of heat treatments (108°, 150°, 174°C). Loss of starch granule-btiefringence was more rapid in high moisture (33%) than in the low moisture (13%) flours at 108° and 150°C. Alpha-amylase digestion rates of starch increased with processing temperatures, in general, and were related to heat-produced physical changes. Basic information on starch granule structure of wheat as revealed by heat and enzyme treatments using the light microscope and scanning electron microscope is presented. The possible applications of the heated starches in food systems is discussed.

Notes: Spores of B. stearothermophilus were heated in a neutral phosphate buffer at temperatures between 111°C and 125°C. A statistical analysis was made to find out how well the temperature dependence of the inactivation rate constants could be described by the Arrhenius equation and the commonly used z-value. The results showed that both models are very good linear regression models, but have a significant lack of fit. Far reaching extrapolations of data by using these models, for example, to very high temperatures should therefore be avoided.

Notes: The color and microstructure of myoglobin preparations obtained by acetone treatment were characterized by reemission photometry and scanning electron microscopy (SEM). When acetone was added to water solutions of myoglobin a microstructure composed of beads with a diameter of 150 nm could be formed. The bead-like microstructure was stable against changes in the composition of the acetone-water medium only when the myoglobin preparation had undergone complete irreversible transition. The bead-like microstructure of preparations having undergone incomplete irreversible transition collapsed to a fused microstructure when exposed to media of higher water content than the preparation medium. The irreversible transition of the preparation thereby increased. Preparations having a bead-like microstructure appeared more lightly colored due to the dispersion of the reemitted light. A similar bead-like microstructure could be obtained upon acetone treatment of a crude acid precipitated protein concentrate from Vicia faba (broad beans).

Notes: Byssochlamys fulva is a mold that produces ascospores which can survive thermal processing and cause spoilage of canned fruit products. The growth of B. fulva was examined in ‘Loring’ and ‘Babygold 6’ peach halves which had been processed in 40° Brix sucrose syrup, removed from cans, and then infected with this organism. Ascospore production and changes in soluble solids, total solids, pH, total acidity, total and water soluble pectin, and texture were determined 2, 4, 8 and 16 days post infection. Results indicated that ascospore production began after 8 days and was not affected by the variety or maturity of the peach. Decreases in soluble and total solids in inoculated peaches after 4 days was attributed to utilization of sucrose and conversion of peach constitutents to volatile components. There was little change in pH and total acidity of the peaches during the growth of the mold. The pectic enzymes secreted by B. fulva resulted in an initial increase in water soluble pectin followed by a decrease in total and water soluble pectins. Textural changes were noted in inoculated peaches as compared to controls. Inoculated mature peach halves of both test varieties softened more quickly than did immature halves.

Notes: In a 4-wk period, wheat bran, substituted for dietary sucrose (50%), caused, in cholesterol-fed young rats, an appreciable decrease in serum cholesterol, triglyceride, and phospholipid levels, and a substantial increase in fecal cholesterol and bile acid losses. Liver cholesterol and triglyceride levels also showed an appreciable decrease. Increasingly finer milling of bran caused a progressive decrease in diet, lipid and cholesterol intake of rats, and in their body and liver weights; fecal mass, as percent of diet consumed, however, remained unaffected. Serum lipid-lowering effect and fecal cholesterol and bile acid losses were accentuated somewhat with decrease in the particle size of bran. Serum chylomicron and beta lipoprotein fractions were substantially reduced in bran-fed rats.

Notes: Simultaneous solubilization of protein and starch in wheat flour was attempted by heating in a dilute acid. Autoclaving a 10% flour suspension in 0.1N HC1 at 121°C for 15 min solubilized more than 90% of the flour solids. The hydrolysate was further treated with activated carbon to eliminate an objectionable wheat flavor. Gel filtration chromatography and SDS-polyacrylamide gel electrophoresis suggested the possible degradation of protein to at least three peptide fractions of 53,500, 30,000 and 〈 11,700 daltons without yielding free amino acids and detectable destruction of essential amino acids. A high temperature Biogel P-2 chromatography indicated an intensive starch degradation yielding 18.7% glucose, 11.3% maltose, 37%oligosaccharides (3–7 glucose units) and 33% higher polymer (8–20 glucose units). The solubilized flour had an apparent viscosity similar to that of pasteurized skim milk and better foamability than those of casein and soybean.

Notes: Ground meat samples were mixed under various conditions of time, temperature, and NaCl concentration to determine the factors affecting the extraction of protein in commercial blenders. Soluble protein increased with mixing time and high NaCl concentrations. The optimum temperature for protein extraction was at 7.2°C. Discrepancies in the relationship between soluble protein and emulsifying ability are discussed for oil volume (ml oil emulsified/25 ml extract) and emulsifying capacity (ml oil emulsified/100 mg of protein). Soluble protein from fresh uncooked, unfrozen meat sources was highly correlated with emulsifying ability irrespective of the original meat source. Freezing or cooking meat, in addition to changing the solubility of proteins, alters the emulsifying ability of extracts containing the remaining noncoagulated soluble protein.

Notes: Growth of Pseudomonas fragi had a significant (P 〉 0.05) effect on the color of beef stored at 1°± 1°C. Beef color was measured with a Hunter Color/Difference Meter and percentages of myoglobin (Mb), oxymyoglobin (O2 Mb), and metmyoglobin (MMb) on meat surfaces were determined using a Beckman DU Spectrophotometer with a reflectance attachment. As surface growth of P. fragi increased from log 2.2 to 7.2/cm2 during 20 days storage at 1°± l°C, the pH increased from 5.5 to 6.6, free fatty acid values (FFA) increased from 0.62 to 2.60 and percent O2 Mb decreased from 100% to 0%. Data indicated that proteolytic and lipolytic degradation products of P. fragi may be important in decreasing the color stability of beef stored at 1°± 1°C.

Notes: Antisera to chicken troponin were produced in rabbits and were effective, in agar gel diffusion reactions, for the identification of chicken flesh in those beef sausages which by law should contain no chicken. Antisera to chicken troponin were reacted with extracts of heated beef sausages containing 1, 3 and 5% chicken flesh. The results indicate that such antisera can detect chicken flesh in beef sausages adulterated at the 1, 3 and 5% levels. Species specificity was demonstrated by a lack of reactivity between rabbit antiserum to chicken troponin, beef sausages and heated pork and lamb flesh. Chances of species cross-reactivity may increase with prolonged immunization. It is recommended that each antiserum be tested for species specificity before “pooling.”

Notes: Gelatinization temperatures of freely dispersed Lima bean starch were determined in pure water and a dilute aqueous salt solution. The composition of the salt solution was based on the hydration medium employed to process quick-cooking beans. Morphological changes in the starch granules during the gelatinization process were examined microscopically. In either an excess of pure water or salt solution the dispersed granules expanded and exhibited a characteristic sequence of explicit configurations. Various stages of gelatinization were characterized in light or scanning electron photomicrographs as: (1) swollen; (2) dimpled or indented; (3) doughnut or erthrocyte-like; (4) rubber-raft shaped; (5) pancake; and (6) dispersed or diaphanous. The dispersed granules retained a veil- or film-like residue which has been defined as a “membrelle.” Gelatinization was initiated at a specific temperature and progressed to completion over a limited temperature. With increasing temperatures, the proportion of granules affected increased until all the granules were dispersed. The gelatinization temperature range was 71–79°C in water and was 79–85°C in the salt solution.

Notes: DSC measurements of water-ethanol mixture in various ethanol concentrations were made in the temperature range from -160°C to +10°C. In the entire concentration range, eight peaks (peaks 1–8) were observed. The heat of every peak (J/g) remarkably changed at 40(V/V)% and 60% ethanol concentrations. At 40% ethanol concentration, the heat of peak 3 (endotherm at -58°C) was at its maximum, while the heat of peak 6 (exotherm at -100°C) was at its minimum. The melting point of ethanol in the mixture was -74°C when the concentration was below 40%, and -62°C when the concentration was above 40%. At 60%, the heats of peak 2 (exotherm at -52°C) and peak 6 were at their maxima. It is, therefore, considered that structural alterations of the mixture occur at 40% and 60%. Peak 3 was ascribed to the melting of strongly-interacted water and ethanol. Similar thermogram patterns were obtamed by the DSC measurements of barley malt whiskey aged for 7 yr in a new oak barrel which was burnt brown and had previously been treated with sherry. However, by comparing the heat of peak 3 of whiskey with that of the mixture, it was known that the interaction between water and ethanol in the aged whiskey was more stronger than that in the water-ethanol mixture.

Notes: It is shown that the conventional (or unweighed) least squares method must not be used to evaluate the B.E.T. constants, Xm and C, when using a rearranged linear B.E.T. plot recently suggested in the literature. This is illustrated using literature data on water sorption in several foods. In this case a semi-weighted (or weighted) least squares analysis becomes necessary. It is also shown that the unweighted least squares analysis should not be applied even to the familiar linear B.E.T. plot. In this particular case, however, and because of a fortuitous coincidence, this procedure leads to not significant differences — at least in food research — in the numerical values.

Notes: Seaweeds were soaked in an aqueous hydrochloric acid solution of pH 1.0 at a temperature below 20°C. After the acid pretreatment, agar was readily extracted by boiling seaweeds in a neutral pH medium. Agars of the highest gelling properties which had ever been known for each of the species of the seaweeds were obtained by this new simplified method. Process control is reliable and cooking time shortened. The possible mechanism of agar separation in the seaweed tissue is discussed.

Notes: The problem of onedimensional heat transfer in finite slabs of freezing food materials cooled from both sides is considered. The authors’ modification to Plank's equation is compared with a numerical scheme. The paper shows that in the important slab freezing problem a simple formula, based on an approximate analytical solution, is at least as accurate as a complex finite difference formulation, and has some substantial practical advantages.

Notes: BONE PARTICLES from five lots of mechanically deboned meat (MDM) from beef neck bones were characterized with regard to size and stability. The largest bone particle diameters were close to the theoretical limit of 460μ but average bone particle diameters ranged from 76.6μ (S.D. = 37.4) to 111.7μ (S.D. = 49.1). Bone particles were stable in MDM but they were readily solubilized in 0.018 – 0.15M HCl.

Notes: Spray treatments with four brands of spray lecithin — PAM®, Mazola No Stick®, Cooking ease® and Griddle Mate®— significantly inhibited light-induced greening and glycoalkaloid formation of potato tubers. Treatment resulted in 93–98% inhibition in chlorophyll formation and 89–98% inhibition in glycoalkaloid formation.

Notes: Instron compression, Warner-Bratzler peak shear force and adhesion measurements, together with subjective assessments, have been used to determine the effectiveness of a pressure-heat treatment in improving the tenderness of post-rigor muscles widely varying in connective tissue content. Both shear force and compression values were decreased by the treatment, the effect being greater on peak shear force values. It had little or no effect on adhesion values, which reflect connective tissue strength. The juiciness of the pressure-heat treated samples was significantly less than that of the controls. It was shown that although peak shear force values were considerably reduced, the tenderness of the treated samples was limited by connective tissue toughness.

Notes: Green beans, corn, peas and asparagus, which were filled in 211 × 011 cans, were subjected to various heat treatments in order to determine the values or reaction kinetic parameters for the thermal destruction of organoleptic quality. Shortly after these treatments, samples were subjected to flavor panel evaluation. Frozen vegetables were used as control samples for the evaluation. Since there were significant heating and cooling lags, each thermal process was mathematically converted to an idealized process with no lag's in the temperature response of sample food. This conversion is based on the use of a mass average sterilizing value estimated from a temperature history curve determined at the center of a can of sample food. Organoleptic quality destruction curves were obtained by plotting the common logarithm of isothermal heating time at which the quality of treated samples became objectionably poor against temperature. From the slope of these curves, the z values were obtained. These values are 52°F for green beans, 57 for corn, and 51 for peas. The z value was not determinable for the thermal destruction of quality in asparagus because of its special response to heat treatments.

Notes: The mechanical properties of a collagenous tissue, the epimysial sheath of the longissimus dorsi muscle, heated to 80° C in buffered saline were studied. In particular, the effects of constraining the tissue during heating and cooling on the final properties of the tissue, and the tension developed during heating, were examined. The elasticity of the tissue after heating and cooling was found to be markedly influenced by the length at which the sample was constrained. The susceptibility of the samples to proteolytic digestion was also measured. An attempt is made to provide a theoretical basis for the observed dependence of mechanical properties on constrained length. Possible implications of these findings to meat attributes are discussed.

Notes: The effect of the interaction of chicken lactate dehydrogenase isoenzyme 5 with carboxymethyl cellulose (CMC) on some kinetic properties was studied. The effect of pH and the concentration of salt, reduced nicotinamide adenine dinucleotide (NADH), and glyceraldehyde-3-phosphate dehydrogenase on binding of chicken LDH-5 to CMC was determined and found to be qualitatively similar to that observed earlier for the interaction of LDH with the particulate fraction of muscle but showed quantitative differences. Modifications of the catalytic properties of LDH on binding to CMC and muscle particles may be due to interactions between the enzyme and the insoluble support or to a change in the microenvironment of the enzyme.

Notes: Changes in TBA values, texture, color, taste and odor were monitored at monthly intervals in samples of deboned flesh prepared mainly from under-utilized fish species and stored at −20°C over a 6-mo period. TBA values were assessed at both surfaces and cores of frozen blocks. TBA values increased most rapidly at the surfaces of blocks prepared from dogfish flesh, whereas those of pollock and grey cod increased at a much slower rate. Intermediate increases in TBA values were shown by blocks prepared from red-banded rockfish, shortspine thornyhead, turbot and ocean perch. In all frozen samples tested, surface TBA values revealed a tendency to steadily increase, then decline after 4 or 5 months. Core TBA values remained relatively constant for most species examined. The exceptions were deboned blocks prepared from dogfish and red-banded rockfish, which showed marked increases after 3 months'storage, and a tendency to decline after 4 or 5 months. Core TBA values were always substantially lower than surface TBA values in all samples examined. Deboned flesh prepared from dogfish and turbot were least firm when cooked; those prepared from grey cod and pollock were appreciably firmer and tended to become even more film during storage. Deboned flesh of ocean perch, red-banded rockfish and short-spine thornyhead were intermediate in firmness and remained so during storage. A block prepared from an equal mixture of pollock and red-banded rockfish flesh revealed a very strong tendency to acquire the firmness characteristics of deboned pollock flesh alone. Examination of color changes in stored blocks before and after cooking disclosed the following: During frozen storage, the deboned flesh of pollock became less dark, while those of shortspine thornyhead, turbot and dogfish revealed a gradual shift in the direction of “yellowness.” Assessment of color after cooking showed that deboned samples of pollock, grey cod and the pollock/red-banded rockfish mixture became somewhat progressively darker with extended storage time. Cooked turbot flesh was lightest in color of all species examined. Assessment of odor and taste revealed that no clear relationship could be found between TBA values and taste panel results. There was a general decline in quality over the six months of storage. A marked loss in quality during the second month of storage and another pronounced drop in quality during the fourth month was observed. The panelists did not consider any of the experimental samples to be of the same quality as the pre-test standards.

Notes: Mouthfeel attributes of dehydrated sweet potato flakes can be predicted by viscometric analysis of puree. Georgia Red, Red Jewel and Rose Centennial were stored at 15°C, 95% RH for 0, 7, 14 and 47 days to insure varying degrees of starch conversion. The flow behavior of the pureed cultivars was analyzed to yield a suitable flow model and apparent viscosity at selected shear rates. The remaining puree was double drum dehydrated and the resulting flakes were evaluated for mouthfeel qualities. The flow index, coefficient of shear rate and apparent viscosity obtained from viscometric analysis were found to be significantly correlated to mouthfeel descriptors used for evaluation of the flakes.

Notes: Recycling was evaluated as a means of alleviating pollution from cherry processing brines. Brines were reclaimed by filtration, treatment with activated carbon, and addition of SO2 and lime. Cherries processed with reclaimed brine were similar in composition, color, and firmness to controls. The capacity of the reclamation system was estimated. Reclaimed brine became discolored if iron exceeded 30–40 ppm. SO2 losses were higher in full strength brines than in weaker brines. Brined cherries repacked in water lost more SO2 than did brined controls and became discolored during storage. Maraschino cherries prepared from water-packed cherries were less firm than controls. Design and engineering studies based on these data are in progress.

Notes: The effect of soy and cottonseed fortification on the nutritional characteristics, storage stability, flavor and color of sorghum was determined. Protein efficiency ratios were significantly higher in blends of sorghum meal with up to 25% defatted, toasted soy than in blends of sorghum meal with liquid cyclone process cottonseed flour. Lysine was found to be nutritionally limiting in blends containing 15% soy or cottonseed flour. Combinations of sorghum grits, meal and flour with 15% soy grits and flour and cottonseed were stored at 49°C for 2 months, 37°C for 6 months and 25°C for 12 months. All combinations displayed adequate stability as measured by changes in available lysine, fat acidity and flavor. Flavor comparisons were made between all-sorghum meal and blends containing up to 50% soy or cottonseed flour. The flavor of all blends was acceptable. There were no preferences between all-sorghum meal and blends containing up to 20% soy or 50% cottonseed flour. Color changes were more apparent with additions of cottonseed than soy.

Notes: Describes a new process (Poly-Protein) for obtaining leaf protein concentrates from alfalfa juice by means of polyelectrolytes. Working conditions and the chemical composition of the products are reported. In particular 50L of juice, obtained by pressing 100 kg of fresh alfalfa, gave 1.6 kg of dry green LPC. The product so obtained has a high protein content and is particularly valuable for its several prospective uses in the feed industry.

Notes: Gross differences in tipolytic bacterial counts in egg products were obtained using Spirit Blue Agar and Polysorbate Emulsion Agar. Changes in total aerobic, proteolytic, and lipolytic counts were monitored in unpasteurized liquid whole egg and in two egg substitutes held at 12°C up to 10 days. Spirit Blue Agar, commonly recommended for the enumeration of lipolytic bacteria, gave suppressed counts in the presence of large numbers of proteolytic bacteria. Polysorbate Emulsion Agar gave more reliable lipolytic counts when lipolytic and proteolytic organisms were present together in the egg products.

Notes: Insoluble fish protein concentrate (FPC) was solubilized by the proteolytic enzyme trypsin in batch, semi-batch and continuous flow membrane raactors. Parametric studies were carried out on the batch system to determine the effects of temperature, pH, enzyme to substrate ratio, and initial substrate concentration on the kinetics of solubilization. The optimum conditions for the batch process were 50°C and pH 9. Product inhibition was found to be significant. At 40°C, pH 9, an initial substrate concentration of 50 mg/cm3, and a trypsin to substrate ratio of 0.001 (w/w), 61 per cent of the initial substrate was solubilized within one hour. In the semi-batch experiments, the effects of temperature, pH, enzyme to substrate ratio, and prewashing of substrate were investigated. The optimum operating conditions for an initial substrate concentration of 50 mg/cm3 were 50°C and pH 8.8 with a trypsin to substrate ratio of 0.002 (w/w). After 4 hr of operation under the conditions stated above, 85% of the total amount of initial solid was dissolved. 62% of the initial nitrogen content appeared in the permeate.

Notes: The kinetics of sausage drying were described in terms of a rate equation and of the diffusivity for moisture in a sausage. The rate equation developed is: dx/dt = -k[(x - c)/x]2, where k is the rate constant, t is time, x is percent yield at any time, and c is the ultimate percent yield at t =∞. Data, as percent yield, are substituted into the integrated form of the equation and values for k and c are obtained. The mean square (MS) of deviations of the data from the theoretical curve was used to test agreement. Heating or fermenting the sausages reduced MS and improved agreement. After extended drying, actual percent yields of sausages approximated yields predicted by the rate equation. Estimation of final percent yield, on the basis of sausage weight early in the drying period, should facilitate efficient production and marketing of sausage. By use of equations developed by Sherwood and Newman, the apparent overall diffusivities for moisture in pepperoni were 5.7 × 10−7, 5.6 × 10−7, and 4.7 × 10−7 cm2/sec, respectively, for pepperoni of starting tat content of 13.3, 17.4 and 25.1%.

Notes: A series of seven tests was conducted to establish a base line for the inhibition of C. botulinum by nitrite in a perishable canned meat product. The product was subjected to abusive storage at 27°C. The degree of variation in swell times and rates among the tests was determined. Predicted average times to first swell were 6.7, 29.8, 82.6 and 94.3 days when 0, 50, 100 and 156 μg/g of sodium nitrite was added to the meat. The primary effect of nitrite appears to have been in determining the length of the lag phase. Once swelling commenced, the rate at which the cans swelled was not significantly different at 50, 100, and 156 μg/g of sodium nitrite. This information will be used to evaluate additives for controlling botulinal growth and toxin production under the conditions described.

Notes: The structural relationships of fat and carbohydrate in the freeze-dried matrix of oil-in-water model emulsions were investigated by using a variety of microscopic techniques (optical microscopy, scanning electron microscopy, and electron microprobe analysis) and solvent extraction methods. The separation of the lipid phase into surface and encapsulated fractions was quantitatively evaluated and the significance of this lipid distribution evaluated with respect to chemical stability of the dried emulsion. The degree of lipid encapsulation in the carbohydrate matrix is shown to depend on a number of process variables, including carbohydrate concentration and morphological characteristics, lipid concentration and freezing rate.

Notes: The interaction between kappa and lambda carrageenan, and milk was examined utilizing three transmission electron microscopy procedures: thin sectioning, frozen thin sectioning and freeze-etching. Discrete fibrils were evident in the thin sectioned and freeze-etched gels whereas nonfibrillar linkages existed among casein micelles in frozen thin sectioned gels. Some micelles appeared to be connected to form small regular clumps in the lambda carrageenan-milk sols. Micelles in the kappa carrageenan-milk gels were aggregated into large irregular clumps. The microscopy method influenced the ultrastructural properties of the sols and gels.

Notes: Phytic acid and nine elements (potassium, magnesium, calcium, sodium, iron, zinc, manganese, phosphorus, and copper) were determined in 12 commercially available cultivars of hexaploid triticales, one octaploid triticale, one wheat and one rye. The amount of phytate phosphorus varied from 1.4–5.3 mg/g in the whole grain, from 0.5–1.9 mg/g in flours and from 0.6–2.2 mg/g in bran of triticales. There were significant variations in the amount of calcium, phosphorus, iron and zinc but not in potassium, magnesium, sodium, manganese or copper due to cultivars. The location had more pronounced effect on micro-elements (manganese, iron, copper and zinc) than on the macro-elements (potassium, phosphorus, magnesium, calcium and sodium). The predominant minerals of triticales were phosphorus, potassium, magnesium and calcium. Phytic acid does not seem to have an apparent correlation with either iron or phosphorus in triticales.

Notes: A relatively simple and efficient chromatographic method utilizing deaminated chitin (Dech), rather than chitin, has been developed and is described for the isolation, purification and concentration of lysozyme from food or biological tissues prior to quantification. It is shown that deaminated chitin has a high specificity and capacity for lysozyme (squid Dech more so than crab Dech), along with good stability and allowing fast flow rates. Studies with fresh egg white, human blood, human milk, goat milk and a commercial hen egg white lysozyme preparation showed recoveries of lysozyme greater than 99%. The various isolated lysozymes were considered to be adequately pure as determined by amino acid analysis and disc gel electrophoresis.

Notes: The phytase (EC 3.1.3.8.) of Sanilac Navy Beans was extracted with 2% CaCl2 and purified by ammonium sulfate fractionation and DEAE-cellulose chromatography. The enzyme showed an optimum pH of 5.3 and Km of 0.018 mM with phytic acid as substrate. The optimum temperature was 50° C. The activation energy of the enzymic hydrolysis of phytic acid was 11,500 Cal/mole and the inactivation energy of the enzyme 55,800 Cal/mole. The purified phytase showed broad specificity. This enzyme may be described as a nonspecific phosphomonoesterase with phytase and potent pyrophosphatase activities. It was inhibited by high concentrations of phytic acid. The activity was increased by about 35% in the presence of 1 mM Co++. Soaking of beans in distilled water did not affect their phytic acid content and phytase activity. Germination of the beans resulted in an increase in phytase activity and breakdown of phytic acid.

Notes: A method for the analysis of patulin in vinegar was developed using gas chromatography-mass spectrometry of patulin acetate. Using selective m/e scanning, patulin acetate can be measured down to a level of 0.04 ppm with a 100 ml sample of vinegar. Commercial samples of vinegar showed no detectable level of patulin. A series of samples fortified with patulin were extracted after 1, 2, 7 and 11 days of ambient storage. 92% of the patulin was converted to nondetectable products in the first 24 hr of storage.

Notes: Frankfurters were cured with various levels of sodium nitrite and sodium erythorbate and evaluated by a consumer taste panel. Color, flavor and overall acceptability decreased with decreasing nitrite concentrations. Flavor and acceptability of frankfurters were increased by the use of erythorbate but only at low (below 52 ppm) concentrations of sodium nitrite.

Notes: Freshly sliced apple tissue was subjected to osmotic dehydration and vacuum drying. The tissue was fist immersed in a 70% sucrose syrup at 50°C for 4 hr which resulted in a 30% increase in total solids due to water loss and sugar uptake. Subsequent vacuum drying produced a product with little browning although no browning inhibitor was used. Analyses of sugars by GLC showed that sucrose and D-glucose levels increased while D-fructose level remained constant during the process. Total organic acid level decreased slightly, contributing to a threefold increase in the sugar-to-acid ratio of the final product compared to the initial apples.

Notes: Protein efficiency ratio (PER), amino acids composition, and nitrogen digestibility were investigated for protein concentrates prepared by alkaline extraction of wheat millfeeds under various conditions. Mean PER (1.88) and nitrogen digestibility (91.6%) were not significantly affected by processing or drying conditions. Protein concentrates from wheat millfeeds represent a potential source of protein and calories in the human diet.

Notes: Published values on the water-holding capacities of various food sources of plant fiber were found to be incorrect. The proper calculation for estimating the water-holding capacity is shown. Corrected values for the water-holding capacity of these foods suggest that on a fresh weight basis, or as consumed, wheat bran is far superior to fruits and vegetables in holding water.

Notes: Antioxidants, citric acid and ascorbic acid did not affect the initial slow oxidation of myoglobin but extended the time before rapid oxidation began. NaCl increased the initial rate of pigment oxidation. Lipid extracted from freshly ground, lean beef increased the rate of myoglobin oxidation when added to freshly ground lean beef while lipid extracted from ground beef stored for 7 days did not. Added linoleic acid was more effective than trilinolein in promoting myoglobin oxidation. Lipase and lipoxygenase enhanced the rate of pigment oxidation while phospholipase A inhibited it. Oxalate inhibited both lipid and myoglobin oxidation and reversed the pro-oxidant capacity of Fe+2. EDTA also inhibited lipid oxidation but promoted myoglogin oxidation.

Notes: Using 1 5 N-labelled sodium nitrite cured pork bellies, with and without the addition of sodium ascorbate, we have attempted to trace the reaction pathways of nitrite in bacon. The depletion of nitrite, originahy at 156 ppm, was followed during the processing operation. Subsequent experiments during the storage of the 1 5 N labelled, sliced, vacuum packaged bacon showed the further depletion of nitrite in both the lean and adipose tissue portions, the lower nitrite levels being found in the bacon to which ascorbate had been added. The formation and depletion of nitrate was also noted. Analysis of the protein and lipid portions showed incorporation of 1 5 N into both. Mass spectral measurements showed that between 73 and 87% of the added 1 5 N remained in the bacon lean portion. The adipose portion contained much less 1 5 N, equivalent to between 20–25% of that added. A hot water extract of both lean and adipose fractions showed the presence of 1 5 N greater than the 1 5 N due to nitrite and nitrate. One effect of the addition of ascorbate was to force 1 5 N into water soluble compounds. Examination of connective tissue protein isolated from the adipose tissue portion showed incorporation of 1 5 N equivalent to 6 ppm NaNO2 in bacon without ascorbate compared to 2.5 ppm for bacon with added ascorbate. 1 5 N data also showed incorporation of approximately 25% of the added nitrite into the muscle proteins of both bacons, and incorporation of 10% of the added nitrite into the lipid fraction of the adipose tissue.

Notes: An improved muscle protein solubility method has been developed which has two distinct advantages over the traditional method: it requires much less time and may be conducted at room temperature. The pre- or post-rigor sample is homogenized in a Brinkman Polytron in 25 ml buffer and is centrifuged. The supernatant is decanted and soluble protein determined as in the traditional method (biuret). Comparable results were obtained for old vs new method for samples of porcine longissimus muscle which encompassed a wide range of sarcoplasmic and myofibrillar protein solubilities. The new method can also be applied with accuracy equivalent to the traditional method for the determination of solubility in cooked meat samples. A four-factor response surface experimental design (central composite) was utilized to evaluate the role of process variables and product ingredients on the cooking losses of USDA Utility grade biceps femoris muscle. The factors were cooking time (0.5–12.0 hr), temperature (55–85°C), NaCl (0–4%), and Na tripolyphosphate (0–0.5%): Shrink was determined on ground 25-g samples by calculating the free moisture lost (as a percentage of total moisture) after centrifugation in Wierbicki tubes. Sarcoplasmic and myofibrillar protein solubility were determined on the same samples by the rapid solubility technique. Stepwise regression was used to tit a multiple polynomial equation to shrink loss and protein solubility (P 〈 0.001). The results indicated that cooking temperature was decisively the most important factor controlling yield and protein solubility. Shrink and protein solubility were nearly independent of time in the center point regions of the experiment which are, based on the type of design (central composite), the most accurate areas for prediction. Previous studies have demonstrated that the major tenderization reactions in beef are dependent both on time and temperature. Therefore, these findings suggest that improved yield in commercial thermal processes is possible by selecting long-time, low-temperature treatments since protein solubility and, therefore, yield are primarily functions of temperature and are relatively independent of time at a given temperature.

Notes: Gamma radiation injured Escherichia coli, Salmonella typhimurium, and Moraxella sp. were studied under various environmental stresses to determine their fate relative to the parent population. Irradiated cultures formed smaller colonies on surface plates with fewer cells per colony. Unirradiated cultures had a shorter lag phase than irradiated cultures in broth and duration of lag increased as a result of increasing the radiation dose. Repeated irradiation and subculture progressively retarded growth rate. Multiple radiation of highly resistant Moraxella sp. showed radiation injured cells to be more sensitive than uninjured cells. With the three species studied, irradiation raised the lower limits of growth temperature, increased the sensitivity to freezing and thawing, and increased the susceptibility to lowered water activity. This work indicated that the production of a bizarre, resistant strain of bacteria through recycling in a food processing operation is highly unlikely.

Notes: The activity of lipoxygenase extracted from tomato fruits can be twice as important according to tomato varieties. Differences between the last stages of ripening agree with the results previouslv reported. The partially purified enzyme (27-fold) is very unstable and can be protected during a limited time by ascorbic acid and EDTA. The fact that it is inhibited by hydrogen peroxide and not by cyanide ions (10-3 M) and EDTA (10-3M) is in favor of a true lipoxygenase and not a hematin compound. The molecular weight of the enzyme was estimated from gel filtration to be approximately 87,000. The enzyme had a pH optimum at 6.3–6.5 and a maximum activity at 40°C. The apparent Km determined in the presence of ethanol is 0.015 μM.

Notes: Several fluorometric procedures have been previously developed for the determination of vitamin B6 compounds in foods. These have mainly been based on the separation of pyridoxal (PAL), pyridoxine (PIN), and pyridoxamine (PAM) by column chromatography on Dowex AG 50W-X8, chemical conversion of PIN and PAM to PAL, and formation of the 4-pyridoxic acid lactone fluorophore by reaction with KCN. These procedures were limited by a cumbersome chromatographic procedure utilizing boiling potassium acetate buffers, and interfering compounds in the PAL fraction often precluded accurate measurement. In this study, Maillard browning pigments resulting from the autoclave extraction procedure were shown to interfere by reacting with KCN to form highly fluorescent products. To alleviate the interference problem, an alternative ion exchange chromatographic method was developed which eliminated the KCN-reactive browning pigments from the PAL fraction. After the ion exchange clean up steps, PAL was determined directly by reaction with KCN, whereas PIN and PAM were fist converted to PAL by reaction with MnO2 and sodium glyoxylate, respectively. The effectiveness of the procedure was demonstrated on casein in the presence or absence of glucose, and on selected food samples.

Notes: Clotting times and complex rigidity moduli (G) were determined with a thrombelastograph during clotting of skim milk by soluble and immobilized pepsin and during rennet-clotting of milk acidified with various acids to pH 5.6. Longer clotting times resulted in slower rates of increase in G; excellent linearity existed between the two factors for clots formed by immobilized and soluble pepsins. For these two enzymes, the approach of G to maximum G was first order with respect to time during most of the clot formation. The type of acid greatly affected G but not clotting time except that samples acidified with citric acid clotted slower. Acids effecting higher G in gels also cause greater retention of calcium in cheese.

Notes: Bakers and brewers yeasts, yeast cell walls (bakers yeast glycan), and a protein isolate from yeast (bakers yeast protein) incorporated into the diets of rats partially or totally prevent the elevation of the serum cholesterol in rats fed cholesterol and cholic acid as a hypercholester-olemic agent. The degree of response depends upon the level of yeast' product in the diet. Bakers yeast glycan incorporated into the diet of hypercholesterolemic rats rapidly and markedly lower the serum cholesterol.

Notes: Visual impressions of fresh meat color are formed by contributions from all three parameters of color, namely, hue, value, and chroma, as well as gloss, relative pigment content, and the presence of surface moisture. It appears that there is a mental “ideal value” for each of these factors and deviations from that ideal in any direction cause the meat to be rated lower visually. Since these deviations may occur in any of the above mentioned parameters, it is difficult for instrumental methods to predict the visual color quality of fresh meats. Equations were developed which could be useful for making accept/reject decisions on pork muscle color.