ALBERT

Notes: Live cells of E. coli O157:H7 were labeled by 4′,6-diamidino-2-phenylindole (DAPI) in buffers of different pH. The extent of labeling was relatively insensitive to pH in the range of 6.5 to 9.5. The fluorescence intensity of ± 104 DAPI-labeled bacteria per mL in optical cuvettes could be detected by a luminescence spectrometer. With a fluorescence microplate reader attachment, less than 103 of labeled bacteria could be measured. DAPI-labeling inhibited the growth and respiratory activities of the bacteria. The addition of 0.5 to 6 mM concentrations of ATP induced a substantial increase in the fluorescence of labeled bacteria. Maximal enhancement by ATP was observed from bacteria still maintaining low levels of physiological activities. The enhancement favored more alkaline media with pH greater than 9. A replacement of ATP with ADP or AMP diminished the extent of enhancement. Other triphosphate nucleotides did not enhance fluorescence of DAPI-labeled bacteria. Comparable ATP enhancements were also observed with Pseudomonas alcaligenes and Shewanella putrefaciens. Solubilization/destruction of cell membranes of labeled bacteria by detergents essentially eliminated the ATP enhancement. Absorption and fluorescence spectroscopic measurements indicated that ATP could interact with free and bound DAPI. These results suggest that observed ATP enhancement in fluorescence intensity of DAPI labels in intact cells may be applied to increase the sensitivity of microorganism detection.

Notes: Fungal biota, with special reference to the genus Penicillium, was studied in 52 samples of commercial cheeses (10 fresh, 17 semiripened and 25 ripened) made from different types of milk (cow, ewe, goat and mixed) produced in southern Spain. In 41 of the total of cheeses analyzed (79%) molds were isolated. Penicillium was identified in 63% of the samples, Mucor spp. in 27%, Geotrichum candidum in 17% and Cladosporium herbarum in 10%; eleven other fungal genera were detected ranging from 2 to 4%. Thirty-five species of Penicillium were analyzed with the following distribution: 7 in fresh cheese, 16 in semiripened cheese and 30 in ripened cheese. The incidence of Penicillium spp. was also greater in the cheeses with a higher degree of ripeness, i.e. 20% in fresh cheese, 71% in the semiripened and 76% in the ripened cheese.

Notes: Challenge studies were carried out on raw, cooked, and sterilized surimi nuggets, inoculated with 104spores/g of C. botulinum type E spores. All products were packaged in air and air with an Ageless SS oxygen absorbent and stored at 4, 12 and 25C. Toxin was not detected in any raw product throughout storage (28 days). The absence of toxigenesis was attributed to the low pH (4.1–4.3) due mainly to the growth of lactic acid bacteria (107CFU/g). Toxin was also not detected in any cooked product after 28 days. Product pH did not decrease as previously (due to the absence of LAB), but counts of C. botulinum still decreased throughout storage. In sterile nuggets, C. botulinum counts increased to 106 cfu/g at both 12 and 25C, respectively, by 28 days. Lactic acid bacteria and Bacillus spp.were not detected throughout the 28 days storage period. Toxin was detected by days 28 and 14 at 12 and 25C, respectively, and toxigenesis preceded spoilage. The absence of toxin in cooked nuggets was attributed to the anti-botulinal role by Bacillus species, the predominant spoilage bacteria in cooked nuggets.

Notes: Packages containing chubs of summer sausage were inoculated with about 108 cfu/mL of a three-strain mixture of Listeria monocytogenes and vacuum sealed. The fate of the pathogen was then monitored after pasteurization at 150F (66C), 170F (77C), 190F (88C) and 21 OF (99C) for 0 to 240 s. Pathogen numbers were reduced by about 3 log10 cfu per gram within 30, 60, or 90s at 21 OF (99C), 190F (88C), or 170F (77C), respectively, whereas numbers were reduced by 〈2.0 log10 cfu per gram after 240 s of heating at 150F (66C). The calculated D values were 2.08 min at 150F (66C), 0.84 min at 170F (77C), 0.37 min at 190F (88C), and 0.28 min at 21 OF (99C). These results establish the feasibility of using pasteurization to control L. monocytogenes in packaged summer sausage.

Notes: Book review in this ArticleWORLD HEALTH STATISTICS QUARTERLY DALLAS G. HOOVER

Notes: Decimal reduction times (D-values) for Saccharomyces cerevisiae ascospores inoculated into pasteurized orang juice ranged from 4 to 76 s at pressures between 500 and 350 MPa. At the same pressures, D-values of S. cerevisiae vegetative cells ranged from 1 to 38 s while those for the native microflora in nonpasteurized Hamlin orange juice were between 3 and 74 s. Corresponding z-values were 123, 106 and 103 MPa for ascospores, vegetative cells and native microflora, respectively. Native microorganisms that survived high pressure treatments included yeasts, gram-positive and gram-negative bacilli. Pectinmethylesterase activity in nonpasteurized Hamlin orange juice was reduced to 5% of initial activity after 30 s at 900 MPa.

Notes: Results from two consumer surveys are presented. In the first, a EU FAIR (European Union Food, Agriculture and Industrial Research Programme), supported project, three-thousand consumers (500 in each of six countries, Germany, Italy, Britain, Spain, Sweden and Ireland) were surveyed in March 1997 on their attitudes to the quality and safety of three meats, beef, pork and chicken. This paper deals with the safety aspects of the survey. Many consumers in all six countries said they were eating less beef and more chicken. Overall, the Spanish and Irish appeared to be the most concerned about the safety of meat, the British were somewhat less concerned. While many were confident that the food in shops is safe, there was a sizeable minority who believed the contrary. When looking for information on the safety of meat, butchers, whether independent or in supermarkets, are the group most trusted by consumers. In terms of consumer concerns, about 60 percent of beef consumers were very concerned about hormones, BSE (Bovine Spongiform encephalopathy), antibiotics and bacteria. Pork consumers had similar levels of concern as beef consumers about bacteria, antibiotics and hormones. For chicken there was a higher level of concern about bacteria (Salmonella) (68% were very concerned) and similar levels of concern to pork and beef for the other issues. Generally, fat was the issue of least concern for all three meats. Freshness was considered to be relatively the most helpful of 7 factors used for assessing safety of meat. The country of origin and what the animal was fed were also considered to be relatively helpful. Factors considered to be relatively less helpful were price and the name of the producer. In the second study, over 1200 pre-leaving certificate Irish school children participated in autumn 1996 in a national survey assessing young people's attitudes to meat. Half of the respondents agreed with the view that eating beef means increasing the risk of getting CJD (Creutzfeldt-Jakob Disease). Those who agreed were more likely to be less frequent eaters of beef and to have reduced their meat consumption in the post-BSE period. It was found also that females were more likely to eat less meat than males and to have reduced beef consumption. The implications of some of the findings of these two surveys are discussed.

Notes: Bovine spongiform encephalopathy (BSE) belongs to a distinct group of transmissible degenerative encephalopathies (TDE) that includes scrapie in sheep and Creutzfeldt-Jakob disease (CJD) of humans. These fatal neurological diseases are caused by unconventional but uncharacterized transmissible agents that have a number of unusual properties; this includes a high degree of resistance to inactivation. The only disinfectant that appears to be completely effective against high titres of TDE infectivity is sodium hypochlorite. Exposure to 1 to 2 M sodium hydroxide has a substantial but incomplete effect, as does autoclaving at temperatures between 132 and 138C for up to an hour; however, a combination of 2 M sodium hydroxide and autoclaving, even at the more modest temperature of 121C for 30 min, appears to be completely effective. With lower titres of infectivity, less rigorous regimes may be effective. For example, although most of the rendering procedures used to manufacture meat and bone meal (MBM) throughout the European Union (EU) have been found to be incapable of inactivating BSE and scrapie agents, one method which appeared to be effective with moderate titres of BSE and scrapie agent, involved exposure to steam at 133C for 20 min. This procedure is now the only one approved within the EU for the manufacture of MBM for feeding animals, excluding ruminants; however, the UK has introduced a ban on feeding MBM to any farmed species because of the occurrence of a new variant form of CJD in the UK which appears to have been caused by the BSE agent. Although the clinical signs of scrapie in sheep are entirely attributable to neurological dysfunction, tissues such as spleen and lymph nodes are known to become infected before those of the central nervous system. In contrast, the only tissues which have been found to become infected in cattle with natural BSE are brain, spinal cord and retina. These are no longer used in animal or human foodstuff. Because scrapie agent has no known association with human disease there has been no restriction in the past on using any sheep tissues, including brain, as human food; however, it is known from experimental studies that the BSE agent can infect sheep by the oral route to cause a disease that is clinically and neurohistopathologically indistinguishable from scrapie. It is also known that the spleen becomes infected in such sheep. Sheep in the UK could theoretically have become infected with the BSE agent through the feeding of infected MBM before the feed-ban in 1988. There are now measures in place that prevent the head, spinal cord, and spleen of sheep being incorporated into foodstuff.

Notes: Considerable time, regulation and consumer concern is associated with the question of chemical residues in food. Potential residues in food span a broad range from natural contaminants (mycotoxins) through environmental contaminants (dioxins, PCBs), agrochemicals (nitrates, pesticides), veterinary drugs (anthelmintics, antibiotics), prohibited substances (hormonal growth promoters), chemicals arising in processing (nitrosamines), packaging components (plasticisers) to contaminants arising in domestic food preparation (heavy metals). The occurrence or avoidance of these chemicals as residues in food is to a greater or lesser extent under the control of the food producer, processor and consumer in the activities of growing/producing, treating, storing, processing, packaging and cooking. The fundamental question is to what extent do or can residues in food constitute a food safety hazard for the consumer. Many of these substances are regulated as to their use and as to their acceptable levels in food while others, by their nature, arise as more random occurrences and, as such, are less prone to regulation. Of particular concern to the producer, processor and retailer of food is what steps may be taken to ensure that the food supply is safe. Best practice in plant and animal husbandry by the producer, in sourcing of material and in control of food manufacturing by the processor, and in sourcing of food products by the retailer combine to assure the safety of food to the consumer. This paper describes the various classes of chemicals which can arise as residues in food, particularly agrochemicals and veterinary drugs, the usage patterns which decrease/increase the likelihood of the occurrence of residues at unacceptable levels, how and in what form(s) residues can occur in foods, and the contribution of food processing to a reduction or otherwise of residue levels in food consumed. Consideration will be given, also, to quantifying the risk posed by chemical residues in food and to a study of the results from a Residue Database and from residue monitoring/surveillance as an indicator of risk to the consumer.

Notes: This paper is concerned with processes and procedures involved in the contamination of beef, lamb and pork carcasses during slaughter. The hides of beef and the fleece of sheep are major sources of carcass contamination. The spread of pathogens from beef hides to the carcass, operatives and surfaces in the abattoir is demonstrated. Efforts to clean the hide of cattle and the fleece of sheep are outlined, with reference to the success of these treatments in reducing carcass contamination. The effect of bringing very dirty or dungy animals to slaughter is considered in terms of the effect on carcass contamination after slaughter. The influence of tying the bung (or rectum) in reducing carcass contamination is discussed, as is the use of plastic bags as an additional control in preventing pathogen spread on pig carcasses. The relationship of this revised procedure in reducing the occurrence of yersiniosis in Norway is shown. The use of a commercially automated system to tie beef bungs is discussed in relation to reducing carcass contamination. A comparison between the removal of faecal contamination on carcasses by trimming or using a new steam-vacuumized system is presented. The effect of preevisceration washing of beef carcasses is described and the rationale relating to bacterial removal using this treatment is discussed. The influence of evisceration as a source of carcass contamination is demonstrated in relation to sheep slaughter. The processes of carcass decontamination using washing with water at different temperatures, steam pasteurization and hot lactic acid are compared in relation to their ability to remove bacteria from beef carcass surfaces. Finally, the effect of line speed and the impact of technology advances on beef and sheep carcass contamination is reviewed.

Notes: During the last few years there is a growing feeling in the Dutch livestock and meat industry that it is essential to change from a product oriented to a more market-oriented production (from quantity to quality). This is mainly due to developments such as a more intense international competition, stagnant or declining meat consumption and negative pressure on the consumers’ image of meat. Counteracting these developments is only possible if every part of the production chain contributes (in close cooperation with each other) to achieve a better control of the whole production process: from conception to consumption. For a number of years an extensive research program has been carried out to set up a system of Integrated Quality Control (IKB). This has led to a “total quality concept” which includes the safety and quality of the product, the production method, care for the environment, and human and animal health. This paper discusses the basic elements (structure and content) of this quality concept. The extent of implementation of the IKB-concept depends on the particular sector, but it is at around 70% for pigs and broilers. For IKB in veal, current participation is over 90%.

Notes: The need for residue testing and controls basically derives from two imperatives, the safety of the food supply and requirements imposed in trade. Maximum residue limits (MRLs) for pesticides, veterinary drugs, intentional food additives and potential contaminants, such as mycotoxins, are set for various food commodities based on toxicological assessment. Regulatory testing on domestically produced goods reveals the prevalence of a particular residue in a specific food commodity and also serves as a means to assess the effectiveness of the product registration system, while testing conducted on imports is primarily a verification of the effectiveness of the regulatory program in the exporting country. For industry, testing is required to demonstrate due diligence or to ensure that a product meets the specifications of an export market or a specific contract. Testing programs should be appropriate to meet the intended use. A survey to determine incidence of violations requires a test that detects residues above the MRL, while a dietary exposure study requires methodology that detects residues with the maximum achievable sensitivity. Tests conducted to certify a product for export or to fulfill the requirements of a contract should ensure that the product is in compliance with the market or contract requirement. If the requirement is “no detectable residues”, a very sensitive test method may be required. In many countries, there is a developing consensus that while government has a role in conducting work that is in the public interest, such as ensuring the safety of the food supply within a level of statistical assurance, it is ultimately the producer of the food who is responsible for the safety of the product or for ensuring that the product meets market or contract requirements. Various aspects of this changing regulatory, trade and consumer environment will be considered, with examples of the roles now played by governments and industry to ensure the safety and quality of food products.

Notes: A simulation model that assesses the risk of acquiring salmonellosis from consumption and handling of chicken was created in an Excel™spreadsheet and was simulated using Risk™. The model simulated the distribution, preparation, and consumption of 1,000 chickens and was designed to determine the relationship between the level of Salmonella contamination on chickens at the processing plant exit and the risk of salmonellosis for consumers of the chickens. A scatter plot of the probability of acquiring salmonellosis from consumption of the chickens simulated versus the Salmonella load on the chickens at the processing plant exit clearly showed that highly (i.e., 〉 100 Salmonella/bird) contaminated chickens at the plant exit did not necessarily pose greater risk of salmonellosis than lightly (i.e., 〈 10 Salmonella/bird) contaminated chickens at the plant exit. Rather, greater risk of salmonellosis was realized from lightly contaminated chickens when they were temperature-abused, undercooked, and consumed by someone from the high risk population.

Notes: Transmissible Spongiform Encephalopathies, or Prion diseases, are fatal neurodegenerative diseases that affect both humans and animals. Examples include Creutzfeldt-Jakob disease (CJD) in humans, Bovine Spongiform Encephalopathy (BSE) in cattle and scrapie in sheep and goats. They are characterized by a long incubation period, ranging from months to years, and a variable length clinical course, both determined by the particular infection and the species involved. Some 170,000 cattle in the UK have been diagnosed with BSE and have been destroyed. In the rest of Europe there have also been cases of BSE, though the numbers involved are much lower. The recent potential link between BSE and a new variant form of CJD has highlighted the importance of controlling both BSE and scrapie in Ireland. Control of the disease in both cattle and sheep is complicated by the long incubation period, the lack of suitable tests and the general lack of detailed information in relation to the biology of the disease. Factors that must be considered in designing an effective control strategy include (1) better understanding of the epidemiology of the disease, (2) developing rapid and reliable tests for the disease, (3) introducing a suitable surveillance system for both BSE and scrapie, (4) minimizing the consequences for farmers that have BSE-infected animals, and (5) implementing and monitoring legislation to prohibit the spread of potentially infectious material. Each of these areas is discussed and it is proposed that the introduction of best available technology in both the diagnosis and surveillance of the national herd could form the basis for an effective program against animal prion diseases.

Notes: This paper describes an outbreak of E. coli O157:H7 that occurred in central Scotland. Edipemiological and microbiological evidence has indicated that the outbreak was comprised of several separate but related incidents, relating to the lunch (attended by around 100 people) held in Wishaw Parish Church Hall, a birthday party held in a public house on November 23, 1996 and retail sales in Lanarkshire and Forth Valley. All isolates of E. coli O157:H7 from individuals in the outbreak belonged to phage type 2 and possessed the verocytotoxin gene VT2. Two hundred sixty-two of these isolates have been subjected to pulsed-field gel electrophoresis (PFGE): all had indistinguishable profiles. There were 496 cases in total. There have been 20 deaths (all adults) associated with the outbreak, the highest number of deaths associated with an outbreak of E. coli O157:H7 infection in the world. Of these, 8 people had attended the luncheon served at Wishaw Old Parish Church on November 27, 1996. The age range of those who died was 69 to 93 years. The outbreak was investigated by the Pennington Group who concluded that the circumstances of the central Scotland outbreak, and the inevitable uncertainties that may surround outbreaks generally, provide strong justification for the precautionary, preventative measures proposed and the recommendations made.

Notes: The objective of this study was to determine if hedonically different sweetness levels in yogurt, determined by the ideal-relative rating methods, affected the consumption of yogurt in a sensory specific satiety test. Fifteen subjects attended a preliminary session, six taste tests and three sensory specific satiety tests. During each taste test, subjects rated yogurt with one of the three levels of sweetness (high, optimum, and low) for six attributes. During each sensory specific satiety test, subjects were offered a large serving of yogurt with one of the sweetness levels. Liking for optimum or high sweet yogurts decreased more after consumption than the liking for the low sweet yogurt, however, the consumption of optimum and high sweet yogurts was also greater, thus confounding the experiment.

Notes: The effect of a warm-up sample on reliability of attribute intensity ratings from descriptive panel evaluations was studied by: (1) using a warm-up sample prior to test samples (WU), (2) using a warm-up sample prior to test samples and providing panel consensus attribute ratings for the warm-up sample to panelists (WUC), and (3) providing no warm-up sample (NWU). The standard deviation of ratings from 7 and 4 of 11 attributes for all samples was smallest in WUC and WU, respectively. In paired t-tests, significant differences were found between duplications in 0, 1 and 4 of 11 attributes in WUC, WU and NWU, respectively. Regression analysis of percent fat vs attribute intensity ratings showed the largest R2 from 6, 2, and 2 of 10 significant regression models in WUC, WU, and NWU, respectively. To maximize reliability of descriptive analysis ratings, WUC should be used.

Notes: The beta-binomial model is combined with a Thurstonian psychometric function to obtain estimates of the parameters of a distribution applicable to replicated difference tests. A method of estimating the variance of d’obtained from these tests is provided. A formula for determining sample size, which is composed of the number of trials (or panelists) and the number of replications, to determine d’is also given.

Notes: The effect of flavor types (natural and artificial), aspartame (APM)/acesulfame potassium (Ace-K) blend ratios (50%/50% - 80%/20% sweetness contribution), and acid levels (50-70% dry basis) on flavor profiles of raspberry beverages was evaluated. Optimum flavor profiles of beverages sweetened with APM/Ace-K blends would have high fruit flavor scores, balanced sourness and astringency and minimal side tastes/aftertastes. Descriptive flavor profilists developed a lexicon of flavor/mouthfeel attributes for evaluating the samples in the design. The design was replicated 3 times. Acid level influenced sourness and sweetness scores; increasing acid levels increased sourness and slightly decreased sweetness. Natural flavor in beverages showed lower raspberry intensities across all acid levels and blend ratios than artificial flavor. APM/Ace-K blend ratio had no effect on flavor/mouthfeel attributes. Additionally, HIS side tastes were minimized across all APM/Ace-K blend ratios. The optimum natural flavor beverage would contain a 60/40 to 75/25 APM/Ace-K ratio with 58-70% acid (dry basis). Optimum artificial flavor beverages would contain 50/50 to 80/20 APM/Ace-K ratios with 57-68% acid (dry basis).

Notes: Two simple methods were followed to determine detection thresholds for the taste of substances in aqueous solution. The methods applied were: a modification of the ascending method of limits and a method based on the use of scales. Detection thresholds were calculated for the four basic tastes (sweet, salty, acid, and bitterness), umami and metallic. Reference substances for each taste were sucrose, sodium chloride, citric acid, caffeine, monosodium glutamate and iron (II) sulfate heptahydrate and the results of the two methods were compared. We found that the threshold values calculated by method ASTM-679 was within the range of concentrations identified with the scales method.

Notes: Proteins in saliva samples taken from twelve subjects immediately before and immediately after tasting astringent solutions were analyzed by high performance liquid chromatography. Although considerable variation in both the qualitative and quantitative protein pattern was observed among individuals, three peaks appeared to be common to the majority of the chromatograms. The tasting of the astringent solutions resulted in detectable changes in the protein profile of the saliva samples, observed in all the chromatograms examined, and attributed to the interactions of the saliva proteins with the astringent phenolic compounds. The appearance of a major peak at 8 min after the tasting of the astringent compounds common to most of the saliva chromatograms was attributed to the formation of soluble protein-phenol complexes.

Notes: Nonparametric models for sensory discrimination methods are developed. In these models, the relationship between the probability of a correct response, Pc, and the measures for sensory discriminability or sensory difference, p1 and p2 are given. On the basis of the models, different sensitivities for triadic tests were compared including 3-AFC and triangle methods with the strong stimulus as the odd sample and with the weak stimulus as the odd sample. Predictions were made which can be tested experimentally.

Notes: A table is provided for testing the significance of R-index values. The use of the table is illustrated and the theory and assumptions behind the method are explained.

Notes: There are many ways in which a laboratory difference test differs from ‘real life’ discrimination of foods. One of these is the interval of time between tasting the two stimuli to be discriminated. To investigate this, judges performed same-different discrimination tests using a citrus flavored beverage as a medium. The time interval between tasting the standard and comparison stimuli was varied. In this initial study, short intervals of zero, 30, 60 s were examined. For judges unfamiltar with the stimuli, performance deteriorated as the time interval increased. For judges familiar with the stimuli, the zero time interval elicited best performance but there was no decrease in performance when the interval was increased from 30 to 60 s. The results were explained by hypothesizing different types of memory trace for the standard stimulus being utilized for comparison with the comparison stimulus.

Notes: To determine quality characteristics of snack chips, six snack chip prototypes containing cowpea flour, cornmeal, wheat flour and cornstarch (26, 34, and 42%) were formulated. Desirable characteristics as determined by three focus groups were a golden yellow color in a thin, smooth corn-chip form with crunchy or crispy texture, greaseless or dry mouthfeel and salty corn flavor. Chips were undesirable if brown-colored, thick, oily or greasy, had either hard or crumbly texture, and had bland, fishy, or burnt flavors. In consumer acceptance tests, commercial products were found to be more appealing than the experimental products. A discriminant model based on instrumental measurements of color and texture from 11 snack chip samples (six prototypes and five commercial samples) correctly grouped 100% of the acceptable and 90% of unacceptable products.

Notes: To find selective and predictive tests in texture profiling, a series of 20 tests and 2 texture profiles were submitted to 25 subjects. Selection was carried out according to ranking, scoring and a texture property knowledge questionnaire. Two profiles were then done on 5 Bolognese sauce and 8 rice samples. Assessors were assessed by Spearman correlation coefficients for ranking tests, F values for scoring, average square canonical correlation coefficients for measuring the dimensionality of individual sample space, product discrimination and response repeatability for both Bolognese sauce and rice samples.Characterization test results showed that subject ability varied widely according to the test and the profile. Only one significant relationship between the texture property knowledge test and rice profile performances was found. More tests were successfully related to one or several texture attributes of both profiles. The ability to complete a complex profile could be discerned, albeit with difficulty, through simple selection tests.

Notes: Instrumental measurement of color places hue in a 360° continuum, but sensory description of color usually refers to distinct hues — red, green, yellow etc. Color evaluation of “Golden Delicious” apples by both an instrumental method and an experienced sensory panel was conducted to determine if sensory panelists perceive changes of golden apple color in green and yellow hues separately or on a hue continuum from green to yellow. Apple color changed from green to yellow during storage. Two different sensory scoring ballots were used to determine if sensory panelists view color in discrete green and yellow hues or on a green-to-yellow continuum. Data collected from this study demonstrated that sensory panelists can detect the color changes of decreasing greenness, increasing yellowness, and color change from green to yellow in an equal fashion. Hue angle represented the best predictor of sensory color perception.

Notes: Interindividual differences in sweet and bitter taste sensitivity were investigated using time-intensity (TI) measurements and multivariate statistics. TI profiles were obtained in triplicate from 25 subjects for 23 sweet and/or bitter stimuli first matched to be approximately equi-intense to 200 mM NaCl. Sweet stimuli, except for the larger sweeteners, were less persistent, and required less time to reach maximum intensity than bitter stimuli. The results of principal component (PCA) and cluster (CA) analyses of the stimuli X subjects matrices for maximum intensity (Imax), time to maximum intensity (Tmax), total duration (Tdur), and area under the curve (Area) suggest that sweet and bitter stimuli do not share common receptors; and that there are at least two receptor mechanisms each for sweet taste (one for sugars and other small compounds, and the other for large sweeteners) and bitter taste (one for PTC/PROP and one for other bitter compounds).

Notes: The objective of this study was to assess the sensory characteristics of potassium lactate (PL) in combination with salt (NaCl) in a model system at common usage levels for meat systems. Using a gelatin-based (3%) model system containing various concentrations of potassium lactate (0%, 1%, 2%, and 3%) and sodium chloride (0%, 0.5%, 1%, 1.5%, 2%, 2.5%, and 3%), a sensory panel (10) selected for salt sensitivity (0.08% threshold or less) scored the intensity of saltiness and bitterness of each treatment combination using a scale of 0 = none and 15 = intense. As salt concentration increased, saltiness increased and bitterness decreased; as PL increased, saltiness and bitterness increased. At 2% salt, the bitterness of PL was masked; however, salt concentrations below and above 2% were less effective in bitterness reduction.

Notes: Multidimensional scaling (MDS) procedures produce maps of stimulus points, the dimensions of which may be sensory and/or physicochemical attributes. Our objective was to test the efficiencies of a cyclic design and a MDS method in the study of saltiness perception. Two levels of NaCl (0.1% and 0.2%, w/v) were added to two nonionic and two ionic gum solutions prepared to two concentrations. Subjects scaled dissimilarities between pairs of solutions and rated each sample for flavor attributes. Solution pairs were selected using cyclic designs. Repeated measures ANOVA determined that added NaCl was the only significant factor affecting saltiness perception. In contrast, from KYST-2A MDS maps, we concluded that saltiness perception was influenced by gum property, gum concentration, presence of calcium and potassium, and related to binding of the sodium ion (Na+) as determined by23Na nuclear magnetic resonance (NMR) spectroscopy. The MDS cyclic design successfully reduced the number of samples and subjects when using experienced subjects.

Notes: Heat stabilities of crude and partially purified soluble (SPOX), ionically bound (IPOX) and total peroxidase (TPOX) from fresh pinto beans were investigated at 55–90°C. Heat inactivation of peroxidase (POX) followed first-order reaction kinetics. Each inactivation curve consisted of two linear parts: initial rapid inactivation (heat-labile) followed by slower inactivation (heat-stable). IPOX showed activation during heat treatment with a highly heat-stable isoenzyme (D90=40 min) which was more heat-stable than SPOX. Activation energies for heat-stable parts of crude IPOX and SPOX were, respectively, 12.1 and 36.4 kcalmol-1 with z values 45.4 and 14.1C°. Heat stable SPOX isoenzymes (D70=22.6) were obtained by 65–95% (NH4)2SO4 precipitation from crude SPOX. Two POX fractions (F1 and F2) were separated from TPOX by ion-exchange chromatography.

Notes: Changes in color of irradiated meat were observed to be species-dependent. Irradiated pork and turkey became redder due to irradiation but irradiated beef a* values decreased and yellowness increased with dose and storage time. The extent of color change was irradiation dose-dependent and was not related to myoglobin concentration. Visual evaluation indicated pork and turkey increased in red ness whereas beef decreased in redness as dose levels increased. Reflectance spectra showed that irradiation induced an oxymyoglobin-like pigment in pork and that both oxymyoglobin and metmyoglobin developed in beef as a result of irradiation.

Notes: Cheddar cheeses with 33% reduced-fat content were prepared with granular soy lecithin, hydrogenated soy lecithin, or oat. Addition of lecithin increased the wet weight yields and moisture of cheeses (P≤0.05). Reflected color values (L* and hab) were increased in cheeses containing granular soy lecithin (P≤0.05). Acid values of cheeses with lecithin were higher than control cheeses (P≤0.05). Concentrations of lecithin at 0.2% (w/w) resulted in visible changes in micro-structure of the cheeses. Granular soy lecithin or oat lecithin added to reduced-fat cheeses resulted in a decrease in flavor quality (P≤0.05). Hydrogenated soy lecithin added to reduced-fat cheeses improved texture quality without negatively affecting flavor quality.

Notes: ‘Chandler’, ‘Oso Grande’ and ‘Sweet Charlie’ strawberries were stored for 8 days at 1 or 10°C, or 4 days at 20°C, either unwrapped or wrapped in PVC film to retard were conducted during the 1 water loss. Total ascorbic acid (AA) content was expressed on a dry weight basis to correct for water loss differences between treatments. Loss of AA was low and did not differ between wrapped treatments at 1 and 10°C, but was much greater at 20°C. Wrapping reduced AA loss by 5-fold at 1 and 10°C and by 2-fold at 20°C. The effect was not due to modification of O2 and CO2 levels in wrapped treatments, which was minimal. The results indicate that water loss had a greater effect on AA levels than temperature. Combining wrapping with storage at 1 or 10°C reduced AA loss by 7.5-fold compared to unwrapped strawberries stored at 20°C.

Notes: Heat transfer characteristics were studied on clarified depectinized peach juices heated in an agitated jacketed vessel. Four types of agitators and several agitation rates were analyzed. Two equations were derived for the density and rheological behavior of peach juice based on the combined effects of temperature and soluble solids content. Overall and internal heat transfer coefficients were also determined. For each agitator, Nusselt number was statistically correlated as a function of the Reynolds and Prandtl numbers, and as the ratio of the fluid viscosity at the bulk temperature to the fluid viscosity at the wall temperature. The power number also correlated with the Reynolds, Froude, and time numbers.

Notes: The effect of moisture content (MC) on texture and properties of extrudates with varied ratios of soybean flour (SF) and wheat flour (WF) was studied. A single-screw extruder was used at screw speed 200 rpm. MCs of blends were 16, 17 or 18%, w.b. The properties of extrudates depended on flow rate of the material during extrusion. The flow rate revealed a nonlinear dependence on the blend composition and the MC at the same volume of filling of the screw feeding section. The expansion ratio of WF or SF extrudates increased with lowering of the MC. Unexpectedly, the expansion ratio decreased with lower MC for the composite extrudates. Optimal extrudate properties at 16% (w.b.) MC corresponded to 80, 90 or 100% (d.b.) WF and 20, 10% or no SF, respectively. At 17 and 18% MC, optimal properties were found for products containing 80 or 90% WF and 20 or 10% SF, respectively.

Notes: Cells of Lactobacillus delbrueckii subsp. lactis I produced hydrogen peroxide at 5°C in sodium phosphate buffer (0.2M, pH 6.5) with or without glucose. However, if the cells were starved by preincubation in buffer alone, glucose or sodium lactate were necessary to cause hydrogen peroxide production at 5°C. Hydrogen peroxide production by nonstarved cells was confirmed to be in part due to a NADH oxidase. The production of hydrogen peroxide by starved cells in buffer plus glucose in the early stage of incubation was associated with the production of a small portion of lactic acid which disappeared upon further incubation. Additional experiments revealed that hydrogen peroxide was produced in buffer containing sodium lactate added in place of glucose. Results suggested the presence of a lactate oxidase in the organism which used D-lactate to produce hydrogen peroxide.

Notes: Soymilk made from lipoxygenase-free soybeans had less cooked beany aroma, less cooked beany flavor and less astringency and was rated darker and more yellow than that made from soybeans with normal lipoxygenase. Sensory descriptive panelists noted no differences between lipoxygenase-free and normal soybeans for milky flavor, wheat flavor, thickness, chalkiness or aftertaste. Tofu made from lipoxygenase-free soybeans had less cooked beany flavor than that made from normal soybeans. There were no differences in cooked beany aroma, raw beany aroma, raw beany flavor, wheat flavor, astringency, hardness, darkness or yellowness. Native-born Japanese, Chinese and U.S. descriptive panelists differed in responses to flavor, texture and color of soymilk and tofu.

Notes: Increasing the concentration of salt (NaCl) or starch in a salt-starch solution depressed the dielectric constant and loss factor relative to a pure salt solution, except for the loss factor when no salt was present. The addition of salt to a starch solution increased the viscosity. Both viscosity and dielectric properties were decreased by mechanical agitation and by action of amylase. Above 10% starch the decrease in dielectric loss was abrupt, corresponding to the increase in viscosity. The changes were hypothesized to be due to an interaction between salt and starch, either through direct binding of the salt, or indirectly through the increase in viscosity.

Notes: Progressive freeze-concentration was effectively applied to concentrate glucose in a model solution. Effective partition constants of the solute between the liquid and solid phases were determined experimentally. The constant was strongly dependent on the stirring rate at the ice front and the advance rate of the ice front. Increasing stirring rate and reduced rate of advance lowered the effective partition constant: an improvement in freeze concentration performance. A concentration polarization model was useful to describe the effects of the operating conditions on the effective partition constant.

Notes: The feasibility of a CO2 evolution method using an IR analyzer to evaluate the shelf life of refrigerated (4deg;C) catfish was investigated. Aerobic plate count (APC), and isoelectric focusing (IEF) of samples were compared with the CO2 evolution rate (CER) determinations. The increase in CER (25.78 to 195.63 Lg−1h−1) for farm raised catfish stored from 0 to 10 days correlated highly with APCs (4.32 to 10.24 log CFU g−1). The IEF data also confirmed the APC and CER results. Catfish spoilage was evident after 6 days at 4°C. Direct measurement of CER is a rapid and effective method to determine the microbial quality of catfish.

Notes: The potential utility of capillary electrophoresis (CE) for differentiation between natural and artificial shark fins was established. Three major protein components (peaks I-III) of shark fins were well-separated and used as parameters for differentiation between natural and artificial shark fins. The height ratio of protein peak III to protein peak I was higher in natural shark fins than that in artificial products. Further, the profile of amino acids in natural dried shark fins was somewhat different from that in artificial samples. The level of tyrosine was especially high (5.11-8.11%) in natural dried shark fins, but low or not detectable (0-0.22%) in artificial samples.

Notes: Restructured hams were made from modified food starch (MFS), kappa-carrageenan (k-c), isolated soy protein (ISP), and processed with different levels of PSE pork [100% Normal, 50% PSE/50% Normal, 100% PSE]. Hams were ground, tumbled for 2h with a brine, stuffed, and water cooked. Bind strength values decreased and expressible moisture increased with addition of PSE pork to the ISP and k-c treatments. Incorporation of MFS decreased bind strength and expressible moisture and increased yields in the 100P treatment. Results indicated MFS enhanced the water retention of PSE pork in a restructured product.

Notes: The addition of dairy proteins to exhaustively washed chicken breast muscle improved the emulsion stability in heated cream layers (emulsions) containing whey protein concentrate (WPC) or whey protein isolate (WPI). The initial weight of the heated cream layers made with WPC or WPI was heavier than those for sodium caseinate (CNate) or milk protein isolate (MPI). The addition of CNate or MPI resulted in decreased emulsion stability and increased inhibition of myosin heavy chain and actin participation in the emulsion formation compared to WPC or WPI.

Notes: The effects of acid (acetic, formic, lactic, propionic) concentrations, plasticizer concentrations, and storage time (up to 9 wk) on mechanical properties, water vapor permeability, and oxygen permeability of solution-cast chitosan films were determined. Measured water vapor permeability coefficients ranged from 5.35 to 13.20 × 10−1 g/m·day·atm. Oxygen permeated coefficients ranged from 0.08 to 31.67 × 10−3 cc O2 m·day·atm. Neither property was affected by storage time. Tensile strength (6.85–31.88 Mpa) also was not time dependent, but elongation (14–70%) decreased with storage time. Lactic acid solutions produced the lowest oxygen permeability values, formic acid the highest. Films formed with 7.5% lactic acid solutions had uniquely high values for elongation at break.

Notes: The changes in concentration of adenosine triphosphate (ATP) and related compounds were examined as well as free amino acids, organic acids, betaines, glycogen and glycolytic metabolites in the Japanese baking scallop (Pecten albicans) during storage at 0° and 5°C. High amounts of free amino acids and glycine betaine were found. Adenosine monophosphate, inosine and hypoxanthine accumulated during storage, but inosine monophosphate was not detected. Hypoxanthine concentration was considered more appropriate as a freshness index than K value. Taurine, glycine and arginine were the main free amino acids and accounted for 91% of the total immediately after death. D-lactate increased, but no substantial change of L-lactate was detected during storage.

Notes: Four methods for evaluating water hydration of 15 whey derivative powders were compared, and results are discussed with respect to the chemical composition of the powders. Hydration capacities between 0.21 and 4.64 mL water/g of powder were obtained, depending on the method used. The filtration/centrifugation method gave the highest hydration capacity, whereas the paste-water retention method gave the lowest. The Baumann test and the paste-water retention method were well correlated with protein and lactose content of the powders, enabling differentiation between hydration capacities of whey protein concentrates (35% proteins) and electrodialyzed whey powders (12% proteins). Reliable characterization of hydration required a combination of methods.

Notes: The form (dry vs prehydrated) and level (0, 0.5, 1.0 and 1.5%) of a konjac blend (KB) were evaluated to determine their effects on the characteristics of a low-fat bologna model system (LFBMS). The system had a pH range of 6.01 to 6.12, moisture 74 to 76%, fat 〈 2.0% and protein 17 to 18%. Prehydrated KB had higher (p〈0.05) texture profile analysis (TPA) hardness values than dry addition, whereas lower TPA values (p〈0.05) were observed as the level of KB increased. In microstructural observation, the addition of prehydrated KB gels caused the protein matrix to appear more swollen in structure as compared to that after inclusion of a dry powder.

Notes: Porosity characteristics of spray-dried microcapsules consisting of whey proteins and anhydrous milkfat were investigated by gas displacement technique, using helium and nitrogen as displacing gases. Microcapsules exhibited molecular-sieve type porosity. True and apparent densities as well as porosity characteristics were affected by wall solids concentration and by core load. Results indicated that about 10% of capsule volume was not accessible to helium. Pore volume inaccessible to nitrogen penetration was affected by core load and solid concentration. Results suggested that porosity, and hence gas-permeation into microcapsules, could be tailored by adjusting microcapsules composition.

Notes: The effects of cooking temperatures, cooling rates, pH, types of emulsifying salts, age of cheese, and sources of colorant were evaluated. Annatto emulsions showed less stability during continuous heating than annatto solutions or suspensions. Increased cooking temperatures resulted in slight decreases in Hunter a and b values, and overall decreases in hue angles. Emulsifying salt blends with increased amounts of sodium citrate resulted in decreased hue angles. Process cheeses made with more than 25% colored cheese showed lower hue angles than those samples made with uncolored cheese only. Whey powder as a source of added solids in process cheese food promoted discoloration, with acid whey resulting in the most pinking.

Notes: Samples of kiwifruit infused with glucose, glycerol or sucrose solutions at atmospheric pressure to aw=0.97 showed smaller failure forces, under compression, than fresh fruit. Calcium lactate in the solution increased failure forces 30–60% depending on the humectant used. Glucose infusion under vacuum to the same aw produced failure forces 〉300% greater than those observed after atmospheric infusion. Solute infusion reduced greatly the elastic component of the rheological behavior. Microscopic observations showed atmospheric solute infusion caused contraction of cellular membranes, degradation of cell walls and intercell contact decrease. Calcium helped maintain cell cohesion. Vacuum infused tissues showed cell wall optical density similar to fresh cells.

Notes: Rigor mortis of cultivated Atlantic salmon (Salmo salar) began to set in 8h after death and was fully resolved 60–70h after death during storage at 0°C. Maximum muscle contraction was observed 24–30h after death. ATP content decreased from 7.25 to 0.14 to 0.09 μmol/g fish from pre-rigor mortis to in-rigor mortis to post-rigor mortis state. The inosine and hypoxanthine contents increased from 0 to 1.20 to 4.06 μmol/ g fish and from 0.08 to 0.33 to 0.84 μmol/g fish during 60h storage, respectively, during 60h of storage at 0°C. Postmortem changes affected salt uptake. The equilibrium salt concentrations of pre-rigor, in-rigor and post-rigor mortis salmon were 0.53, 0.66 and 0.75 g/g salt-free solids, respectively, in a 20% (w/v) sodium chloride solution at 10°C.

Notes: The effect of three ingredients (triphosphate, lecithin and sucrose ester) on functionality and extractability of hake muscle proteins that had been intensely aggregated by frozen storage was investigated. Muscle proteins were extracted in 0.6M NaCl, 2% sodium dodecyl sulfate (SDS) and 2% SDS+5% (β-mercaptoethanol (ME). Treatment with the added ingredients increased the amount of protein extracted when secondary interactions were broken with SDS. The same effect, although less pronounced, was found in the lots treated with triphosphate and sucrose ester when electrostatic bonds were broken with NaCl. The amphipathic ingredients (lecithin and sucrose ester) increased the amount of protein linked by nondisulfide covalent bonds.

Notes: The application of high pressure (200 and 400 MPa, 30 min) favored water and fat binding properties of chicken and pork batters even at low ionic strength. Textural properties of meat batters (particularly hardness and chewiness, and to a lesser extent springiness and cohesiveness) were influenced by cooking temperature. High pressures influenced the texture of batters, so that pressurized samples were less hard, cohesive, springy or chewy than nonpressurized samples; this effect was not related to on salt concentration. High pressure treatment limited the formation of gel structures, which probably was associated with its preserving effect against thermal denaturation of meat proteins.

Notes: Depectinized control (CTJ) and ascorbic acid treated (AAJ) apple juices were filtered through microfiltration (MF, 0.2 m) and ultrafiltration (UF, 0.02 m) ceramic tubular membranes. Under optimal conditions (8 m/s, 414 kPa and 50°C), the UF membrane resulted in higher steady state flux and less fouling than the MF membrane for both juices. AAJ produced by addition of AA at milling had lower flux for both MF and UF. The chemical, physical and sensory properties of apple juices from MF and UF membranes were similar and changes during storage were comparable.

Notes: Blends were developed to provide 20% protein, 12% fat, 68% carbohydrate and 8% moisture. High protein soy products (full fat flakes, protein isolate and/or concentrate) were formulated with corn meal and soybean oil to provide high protein and fat. The blends were extruded to provide pre-cooked foods that could be reconstituted at 40°C to a porridge or gruel, eliminating prolonged cooking or degradation of heat labile nutrients. Two types of soy isolate and concentrate were evaluated under extrusion temperatures from 100 to 130°C and feed moistures 8.5 to 18%. The extrusion of lower valued concentrates at 100 to 115°C with moisture from 12 to 18% produced a precooked mix that was high in nutrients and contained the most available lysine.

Notes: Initially, the effect of water activity (aw) on heat resistance of Bacillus cereus spores (decimal reduction time) was investigated. A linear relationship was found between log D and 1-aw. The combined effects of temperature (85-105°C), pH (4.5-6.5) and water activity (0.80-1) were then studied. A four parameter model was fitted to the data. This model appeared to be parsimonious with each parameter having a biological significance. Interactions between factors were observed but they accounted for 〈2.4% of the total variation and they were not taken into account by the model.

Notes: Survival of Escherichia coli O157:H7 in apple cider containing no preservatives, 0.025% dimethyl dicarbonate (DMDC), 0.045% sodium benzoate (SB), 0.0046% sodium bisulfite (NaS; 65.5% sulfur dioxide), or a combination of NaS and SB (NaS/SB) and stored at 4, 10, and 25°C was evaluated. E. coli O157:H7 survived for up to 18 days at 4,10, and 25°C in unpreserved apple cider. At 4 and 10°C, DMDC was most efficient at inactivating E. coli O157:H7, generally followed by NaS/SB SB, and NaS (p〈0.05). E coli O157:H7 was more resistant to preservatives at 4°C than at 25°C (P 〈 0.05). E. coli O157:H7 was sublethally injured in cider containing preservatives, and to a lesser extent, in unpreserved cider. Generally, injury was more pronounced in cider containing DMDC, followed by NaS/SB, SB, and NaS (p〈0.05).

Notes: Brown soda bread had a pH of 7-9 depending on the sodium bicarbonate concentration. Part-baked bread developed ropiness after two days at room temperature. Bacillus subtilis, B. pumilus and B. licheniformis were isolated and their spores displayed D-values in bread dough of 14, 10 and 56 min at 100°C. Germination and growth was examined in broth at pH 6-10 and at 4°, 20°, 30° and 37°C. No growth was observed at 4°C and at pH 10. Rebaking of the part-baked bread heat activated particularly B. licheniformis spores.

Notes: The effects of wheat protein on the texture properties of mechanically separated poultry (MSP) smoked sausages were investigated by a partial 3*3*3 factorial design (water, wheat protein and method of protein preparation) with two blocking factors (3 time periods and 9 panelists). The methods of wheat protein preparation did not influence any measurement. Sensory data indicated that added water affected hardness, springiness, and juiciness (p〈0.05) of samples, and added wheat protein affected hardness, cohesiveness of mass, juiciness, and wheat flavor (p〈0.05). Instrumental data showed that Hardness, Springiness and Cohesiveness decreased with increasing water content. (p〈0.05), and increasing wheat protein levels increased Hardness and Cohesiveness (p〈0.05).

Notes: Addition of whey protein concentrate (WPC), whey protein isolate (WPI) or soy protein isolate (SPI) to salt-soluble muscle proteins (SSP) decreased the gel strength. WPI:SSP gels had higher water-holding capacity than SSP, SSP:WPC or SSP:SPI gels. Myosin heavy chain was a principal contributor to gel network formation in SSP, SSP:WPC, SSP:WPI and SSP:SPI systems. The characteristic fibrous network formed by SSP was the dominant feature of the microstructure of SSP:WPC and SSP:WPI gels. SSP:SPI gels had a more aggregated appearance due to the occurrence of clusters of SPI throughout the gel matrix.

Notes: Incorporation of palm oil (PO) increased the α-and γ-tocotrienol content of eggs, liver, meat and adipose tissue. Total tocotrienols were higher in eggs, liver and adipose tissue of hens fed 1.5% PO than those fed 3.5% PO. An increase in retinol was observed in the eggs, liver and dark meat of hens fed PO diet. Feeding diets containing 1.5 or 3.5% PO increased the α-and β- carotenes in eggs and liver tissue. However, carotenoids were not detected in white meat, dark meat or adipose tissue. Dark meat incorporated higher levels of tocopherols and retinol than white meat. The diets had no effect on egg or yolk weight. Egg yolks from hens fed PO had higher yolk color than those without PO. Addition of tocopherol mix in the control diet increased total tocopherol content in all tissues.

Notes: Nondialyzable model Maillard reaction products (MRPs) were prepared by heating 0.8M D-glucose or D-fructose with 0.8M L-lysine under different reaction conditions and times. The usefulness of derived MRPs, with highest melanoidin yields, in stabilizing oxidative deterioration in food was evaluated in a flour-lipid dough mixture with or without cupric ions. Glucose-lysine MRPs effectively reduced lipid oxidation both with and without cupric ions. In contrast, fructose-lysine MRPs lowered lipid oxidation only without cupric ions, and accelerated lipid oxidation with cupric ions. Application of MRPs in combination with α-tocopherol showed no synergistic or antagonistic effect. Conditions and type of reducing sugar in synthesis of MRPs can influence their anti- or pro-oxidant activity.

Notes: The effect of chlorine dioxide (ClO2) treatment on nutrients of seafood was studied using Atlantic salmon (Salmo salar) and red grouper (Epinephelus morio) with five volumes (1:5, w/v) of aqueous ClO2 at 20, 40,100, and 200 ppm ClO2 in 3.5% brine for 5 min. Compared to nontreated controls, treatment of salmon and red grouper with ClO2 solutions in brine did not significantly change the contents of protein, fat, moisture, niacin, calcium, iron, phosphorus, or potassium. However, such treatment with brine or ClO2 solutions in brine caused a significant reduction in thiamin content in both species, but only riboflavin was reduced significantly in red grouper, possibly due to the solubilization effect of salt on the vitamins.

Notes: Fresh Indian mackerel (Rastrelliger kanagurta) was exposed to gamma radiation at dosages of 0,1.5 and 3 kGy. The meat was collected and subjected to a four-step washing treatment. Homogenates of the washed meat in cold (〈10°C) water exhibited apparent viscosity, which was dependent upon protein concentration. Warming the homogenate to 45°C or reduction of its pH to 3.5 by acetic acid decreased the viscosity. Proteins in the low-viscosity dispersion were stable to heating at 100°C while incorporation of NaCl at 5 mM prior to heating resulted in protein precipitation. Gamma irradiation did not affect the viscosity, solubility or stability of the muscle proteins in water.

Notes: Gels were made from recombined milks containing 0, 1.5 or 3.5% fat that were heated at 75, 80 or 90°C for 30 min, followed by acidification with glucono-8-lactone at 30°C. The rheological and microstructural properties of acid gels were investigated using dynamic low-amplitude oscillatory rheology and confocal scanning laser microscopy (CSLM). Heating milks, at temperatures ≥80°C, increased the storage moduli (G′) and decreased the gelation time. Recombined milks containing high fat (3.5%) had higher G′ than gels made from low-fat or skim milk. Milk heat treatment resulted in gels with a cross-linked microstructure. Recombined fat globules appeared to be embedded in the protein matrix.

Notes: Effects of high pressure treatment on guava juice pectic substances and related juice characteristics were investigated and compared with heat treatment. The viscosity and turbidity of guava juice pressurized at 600 MPa and 25°C for 10 min increased slightly; whereas the viscosity of juice heated at 95°C for 5 min decreased while turbidity increased. There were no apparent changes in water soluble, oxalate soluble and alkali soluble pectin in pressurized juice. However, heat treatment of juice decreased water and alkali soluble pectins and slightly increased oxalate soluble pectin. High pressure treatment resulted in no marked changes in pectic and cloud substances of guava juice, and maintained the natural viscous of the juice.

Notes: Chemical spray parameters, including temperature, pressure and exposure time, were evaluated for their effects on reducing Salmonella typhimurium on chicken skins. Pre-chilled chicken carcass skins were inoculated with S. typhimurium and sprayed with 0.1% cetylpyridinium chloride (CPC), 10% trisodium phosphate (TSP), or 2% lactic acid (LA). In the CPC spray, the 40°C treatments resulted in the greatest bacterial reduction. The most effective spray temperatures for LA and TSP treatments were 40 to 55°C. All chemical spray treatments at 207–1034 kPa reduced S. typhimurium. The reduction of S. typhimurium was greatest in all treatments when sprayed with 90 sec spray and 90 sec setting time.

Notes: The objective of this study was to determine if Oatrim, a product developed for use as a fat substitute, could also reduce plasma cholesterol due to its soluble dietary fiber content. Diets with soluble fiber contents of 0% (oat hydrolyzate) or 4.2–4.3%β-glucan from oat or Oatrim were fed to hamsters for 21 days. All oat derived diets reduced serum cholesterol compared to a control diet containing cellulose (p≥0.05). The available carbohydrate produced by the Oatrim process correlated inversely (r20.95) with low density lipoproteincholesterol concentration.

Notes: After storage for 3 wk at 4°C and ripening 3 days at 20°C, nonmelting-flesh peaches(‘Oro A’, FL 90–35C, FL 90–47C) did not develop visual symptoms of mealiness, while melting-flesh (MF) fruit (FL 90-20, FL 90-21, FL 91-16) did. Sensory evaluation showed that only MF fruit were more “mealy” and less “sweet” and “peachy” as a result of chilling. Volatile analysis revealed that chilling caused increases in(E)-2-hexenal and decreases in γ and δ decalactones in both MF and NMF types. However, the decline was considerably less in NMF than in MF fruit. Results indicate that chilling affects the quality of MF more than NMF genotypes.

Notes: The effect of three rapid decompression methods to clear the mechanism of inactivation of heat tolerant spores of Bacillus stearothermophilus IFO 12550 was investigated. Pressurization of the spores at 200 MPa and 75°C for 60 min caused a kill of 104 CFU/mL by the link-motion system but the nonrotational rod valve and E.G. seal methods gave a kill of about 103 CFU/mL. Sterilization was due to the physical breakdown of spore coat, and was induced by its physical permeability of water at high pressure and temperature. Rapid decompression by the link-motion system at 200 MPa decreased the D-value of the spores from 3000 min (100°C, one atmosphere) to 6 min, 11 min, and 17 min at 95, 85, and 75°C, respectively.

Notes: A survey of boneless hams processed in elastic rubber nettings showed that 32 of 59 contained over 100 ppb N-nitrosodibenzylamine (NDBzA) on the surface. These findings demonstrated the need to reduce the nitrosamine content. Nettings made with rubber thread reformulated with zinc diisobutyldithiocarbamate vulcanizing agent were evaluated for their effect on reducing the nitrosamine content. The N-nitrosodiisobutylamine (NDiBA) values ranged from 4.6 to 33.5 ppb (mean 16.1 ppb) compared to 52.3 to 739.9 ppb NDBzA(mean 191.2 ppb) in the control hams. No detectable nitrosamines were found in the unused experimental nettings. The low amounts of NDiBA found on the outer surface of these hams suggested that the use of these new nettings would provide a beneficial alternative to nettings currently in use.

Notes: Beef heart surimi was prepared in the presence or absence of propyl gal late and blended with or without cryoprotectants (sorbitol, sucrose) prior to frozen storage at 15°, 29°, and 70°C up to 52 wk. Protein solubility, gelling characteristics, water-holding capacity, cooking yield, and emulsifying properties decreased during storage at 15° and 29°C for control surimi (without cryoprotectants). Propyl gallate alone did not influence functionality changes. However, functional properties were largely protected by cryoprotectants as well as at 70°C independent of cryoprotectants. Thus, unless extremely low temperatures are used, beef heart surimi subjected to long-term cryogenic storage should be mixed with cryoprotectants and antioxidants to preserve functionality.

Notes: Surface topography and roughness of garlic and onion skins were studied by atomic force microscopy in order to estimate the surface area. Image-processing and Arc/Info software were used to interpret the data. The calculated ratio between apparent and measured surfaces (roughness factor) deviated from 1.11 to 1.15 for untreated and chloroform-treated onion skin, respectively. For garlic, higher values were detected for the untreated skin. The higher the roughness factor, when the coating solutions are easily spread on the fruit or vegetable surfaces, the better the adhesion between coating and skin. A knowledge of true surface areas can help to better estimate required coating-solution volumes.

Notes: A continuous extrusion process to provide instant corn flour for tortillas was evaluated. Variables investigated included two types of mill (knives and hammer) with screens with two diameters (0.5 and 0.8 mm), two types of corn (hard endosperm or normal and soft endosperm or cacahuazintle), lime concentration (0.15 and 0.25% w/w), processing moisture (45 and 48% w/w) and temperature (70,80 and 90°C). The water absorption capacity, water solubility index, color of instant corn flour, adhesiveness of masa, tensile strength, cutting force, rollability and puffing of tortillas, were compared. Based on textural data the hammer mill with 0.8 mm sieve, normal corn type, 0.15% lime, 48% moisture and 90°C processing temperature, produced the highest quality tortillas.

Notes: Microbiological changes during smoking and drying salmon strips using Alaska Native subsistence processing methods were determined. Chum salmon strips handled with or without gloves were brined, smoked and dried at ambient temperatures in two smokers (manual and automated). Water-phase salt increased from 2% to 12% and water activity decreased from 0.98 to 0.85 during smoking and drying. Aerobic plate counts increased from 103/g to 107/g while coliform counts increased to 105/g in strips from the manual smoker as a result of airborne contamination. Strips handled without gloves contained 105Staphylococcus aureus/g. Sanitary handling and air quality control will enhance seafood safety while maintaining product quality attributes.

Notes: Electromyography recordings (EMG) were performed on 10 naive and 10 trained subjects during mastication of different samples of beef. For each group of subjects, ordinary mastication was compared to mastication accompanied by tenderness assessment of the chewed sample. Trained subjects showed a larger variation in muscle work than a naive group when chewing. Sensory assessment modified more the mastication profiles of trained subjects than those of naive ones and these variations occurred at the beginning of the masticatory sequence. EMG was useful for comparing mastication of different groups of panelists and appeared to be an interesting alternative for information about texture perception of naive subjects.

Notes: Raw-meat patties were prepared from three pork muscles, irradiated in different packaging environments, and stored for 0 or 3 days before cooking. Lipid oxidation by-products were formed in the raw meat during storage and the baseline lipid oxidation data of raw meat was used to measure the progression of lipid oxidation after cooking. Thiobarbituric acid-reactive substances (TBARS) and volatiles data indicated that preventing oxygen exposure after cooking was more important for cooked meat quality than packaging, irradiation, or storage conditions of raw meat. Propanal, pentanal, hexanal, 1 -pentanol, and total volatiles correlated highly (P 〈 0.01) with TBARS values of cooked meat. Hexanal and total volatiles represented the lipid oxidation status better than any other individual volatile components.

Notes: Samples containing various levels of vitamin D and riboflavin, with and without ascorbic acid or a-tocopherol were prepared in a model system. Samples were stored in the light or in the dark at 45®C for up to 8 h. Headspace oxygen was determined by gas chromatography with thermal conductivity detection. Oxidation of vitamin D was not observed in samples without riboflavin stored in the light nor in samples with riboflavin stored in the dark. Vitamin D with riboflavin was oxidized under light. α-Tocopherol quenched singlet oxygen at a rate of 2.52 × 108 M-1 sec-1, whereas ascorbic acid quenched singlet oxygen at a rate of 2.23 × 107 M-1 sec-1.

Notes: Isometric rigorometry was used to study rigor tensions in “rested”, “partially exercised” and “exhausted” chinook salmon (Oncorhynchus tshawytscha) white muscle at the pre-mortem acclimated temperature. Conservative handling and anaesthesia (AQUI-STM) minimized pre-mortem exercise and provided “rested” fish. Post-mortem electrical stimulation produced “partially exercised” (180 contractions) and “exhausted” (360 contractions) muscle. A “relaxation” stress that decreased with increasing exercise was measured. The amplitude of the “relaxation” and contraction stress was the same for each treatment (F2,12= 0.24; p=0.79). Rigor contraction onset coincided with an intra-muscular pH of 6.6 in each treatment (F2,12=0.28, p=0.76). Contraction stress abatement coincided with an “ultimate” pH of 6.2 in each of the treatments (F1,12=0.05; p=0.83).

Notes: Time lapse video was used to determine the effects of temperature and fatigue on the development of rigor contractions in chinooksalmon (Oncorhynchus tshawytscha) white muscle. Minimal handling and chemical anaesthesia (AQUI-STM) produced rested fish. After removal of one fillet from the rested fish, post-mortem electrical stimulation of the carcass was used to partially exercise the remaining muscle. Specific strips of rested and partially exercised muscle were held in physiological saline at 0,4,6,8 and 12°C. Contraction onset and end were delayed by decreasing temperature in the rested treatment, but were unaffected in the partially exercised treatment. The final contracted length was affected by fatigue state and temperature.

Notes: Ground beef-based beefsticks were produced with glycerol levels of 0, 2, and 4%, and dried to water activity levels of 0.90 and 0.85. Samples were analyzed by uniaxial compression and colorimetry after production and after 52°C storage for 1, 2, 3 or 4 wk. Deformability modulus, percent recoverable work, relaxation properties, and relative lightness were calculated. Glycerol, as well as water, acted as an effective textural plasticizer. Reductions in modulus and relaxation parameters due to glycerol addition were in the range of 30–40%. Glycerol can thus effectively be used to adjust physical properties without compromising stability. Higher moisture samples were relatively more elastic, as determined by recoverable work. High temperature storage reduced modulus, solidity and percent recoverable work (20–70%) in all samples.

Notes: Spray-dried powders with 50% butteroil encapsulated in sucrose were double-encapsulated by dispersion in a molten matrix of vegetable waxes (high-pressure-treated by a patented process) followed by pressure treating at 414 KPa and sieving. A 20–40% increase in particle size resulted from double encapsulation and powders were less flowable (P 〈 0.01). Scanning Electron Microscopy of double-encapsulated powders showed one or more sucrose-encapsulated particles embedded in a matrix of solid vegetable wax. Double coating reduced moisture uptake by 20%, possibly ameliorating the need for special packaging during storage. The flow and mechanical behavior of the encapsulated powders were different (P 〈 0.05) from the other powders studied.

Notes: Addition of locust bean gum (LBG) or guar gum to ice cream mixes gave products with smaller ice crystals after heatshock than control samples without either stabilizer. LBG was more effective at inhibiting recrystallization than guar. Increasing stabilizer concentration resulted in greater inhibition. With LBG we found some evidence for an optimum concentration above which no further inhibition occurred. We found no evidence for phase volume effects.

Notes: Differences in texture and histological structure of Chinese cabbage (midribs) pressurized at room temperature or ca. -20°C were investigated. Use of rising pressure at room temperature enhanced de-esterification of pectin in midribs and increased firmness and rupture strain. When samples were frozen at 100 MPa (ice I formed) and at 700 MPa (ice VI), rupture strain increased. However, texture of samples frozen at 200 MPa (liquid), 340 MPa (ice III), 400 MPa (ice V) was comparatively intact. Release of pectin and histological damage in midribs frozen at 200 and 340 MPa were less than midribs frozen at 100 and 700 MPa. High-pressure-freezing was more effective in improving both texture and histological structure than freezing (-30°C) at atmospheric pressure. However, texture of high pressure-frozen midribs (pliant) was greatly different from raw midribs (crisp).

Notes: Based on dynamic rheological measurements, sucrose, glycerol and magnesium chloride (MgCl2) prevented egg yolk gelation at concentrations of 2% and higher. These additives showed improved cryoprotectant effects as their concentrations were increased. Sodium chloride (NaCl) at higher than 2% also prevented gelation but at 10%, it caused a considerable increase in viscosity of unfrozen yolk. Calcium chloride (CaCl2) showed an opposite effect, promoting protein coagulation before freezing. Samples with 2% CaCl2 gelled completely after 36h at -24°C. Before freezing, potassium chloride (KCl) in the range 2–10% had an effect similar to that of NaCl. However, after freezing its effect changed. Yolk with 2% KCl, frozen 36h at -24°C, showed very elastic behavior.

Notes: A mixed culture (Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus) was inoculated into reconstituted skim milk and incubated. When 0.45 Unit/g or more of lactoperoxidase (LPO) was added, the yogurts had softer and smoother texture than untreated yogurt. The apparent viscosity of yogurt was also reduced by addition of LPO. The storage modulus (G') of the gel of LPO-treated yogurt decreased but the frequency-dependency remained unchanged. The amount of exopolysaccharide or degree of proteolysis in yogurt was not changed by addition of LPO.

Notes: We studied the effect of CO2 and gibberellic acid (GA3) on postharvest senescence of parsley (Petroselinum crispum Mill.) and on ethylene induced senescence. GA3 or CO2 treatment retarded, with a similar efficiency, chlorophyll and protein degradation, amino acids accumulation and respiration rate. Treatment with GA3 and CO2 together resulted in an additive senescence retarding effect. The promoting effect of ethylene on senescence could be retarded with either CO2 or GA3. Thus, GA3 and CO2 could provide an effective means for maintaining fresh produce quality in parsley.

Notes: Ascorbic, isoascorbic, metaphosphoric, and gluconic acids improved the regeneration of red beet juice pigments after heating, and resulted in greater retention of the pigments during processing and storage. Their effect varied depending on the pH of the juice solutions. Ascorbic and isoascorbic acids allowed for the greatest regeneration at pH 3.8. At pH 6.2, metaphosphoric acid and gluconic acid were more effective. Addition of ascorbic acid once prior to the first heating retained the initial concentration of pigments even after 5 cycles of heating (3 min at 100°C) and regeneration. Control solution lost red pigments completely.

Notes: Chicken breast meat yielded three endothermic transitions, with peak transition temperatures of 53,70, and 79°C. Comparison with the purified protein fractions indicated that these transitions corresponded to denaturation of myofibrillar (53°C) and sarcoplasmic (70 and 79°C) proteins. The apparent specific heat profile of chicken breast meat was successfully modeled as a weighted average of the apparent specific heat of the constituent proteins. The specific heats of sarcoplasmic protein, myofibrillar protein, and chicken breast meat were strongly influenced by temperature; however, the specific heat of stromal protein was nearly constant across the temperature range considered (i.e., 10 to 100°C).

Notes: Storage of ripe olives in liquids with high acetic acid content under anaerobic conditions led to glucose accumulation, low ethanol, and high chemical oxygen demand (COD). In contrast, low acid concentrations and anaerobic conditions produced a high level of ethanol and slightly lower COD while aerobic conditions produced low glucose, ethanol and COD. Surface color of ripe olives improved when storage liquids were used in the second washing of the darkening step. Firmness also increased with increasing proportion of storage liquids reuse, although olives from highly acidic media were softer than those stored in low acid media.

Notes: A procedure for determination of net syneresis in starch and flour materials was developed based on free water in freshly cooked pastes, syneresis water expelled during cold storage and absorbed water in the contracted gel. Free water values decreased from 50% to 〈5%, as starch concentrations increased from 4 to 10%, indicating the need for correction of expelled+absorbed water values from free water for calculating net syneresis. Normal cereal, root and dicotyledonous seed starches exhibited a broad range of expelled water values during refrigeration, but gave high absorbed water values during freeze-thaw cycles. Waxy starches had low net syneresis during refrigeration and, except waxy corn, during freeze-thaw. For comprehensive evaluation, two refrigeration and two freeze-thaw cycles are recommended.

Notes: Experiments were performed to evaluate the antibacterial properties of liquid smoke (LS), against E. coli O157:H7, in model (agar) and meat systems. The effects of 8% LS on growth of E. coli O157:H7 attached to ground beef, and 1.5% LS on warmed-over flavor (WOF) in precooked beef patties were also studied. E. coli O157:H7 growth was reduced (p〈0.05) 2.3 log10 CFU/g in ground beef patties after 3d refrigerated storage. TBA numbers, aroma scores and pH values were lower (p〈0.05) in LS treated beef patties. LS reduced undesirable flavor development and may help assure the safety of beef products.

Notes: Forty-three samples of shellfish (22 mussels and 21 clams) purchased from retail outlets from February through October were tested for the presence of vibrios associated with human disease. Vibrio spp. was found in 51.16% of the samples. V. alginolyticus was the commonest Vibrio species found in the samples, followed by V. parahaemolyticus, V. fluvialis and V. cholerae non-01. All V. parahaemolyticus isolated were Kanagawa-phenomenon negative. Hemolytic activities were shown in all isolates of V. fluvialis and V. cholerae. Bacterial indicators of quality and safety were within permitted limits by authorities. The results indicate the potential risks of food poisoning associated with the consumption of raw or undercooked shellfish.

Notes: Meat and meat products are important vehicles of foodborne illness outbreaks in European countries. Salmonellas were the most commonly reported aetiology of infection, although the relative importance of other agents varied. The factors contributing to the increase in food poisoning and salmonellosis in England and Wales related both to foods eaten and their preparation. The implication of foods of animal origin as principle vehicles of infection was strengthened by reports associating these foods with outbreaks of human illness, and reports of salmonella infection in animals and poultry. The current increase in salmonella infection associated with poultry products suggests that reducing infection in, or contamination of poultry could significantly decrease human illness.The problem of human salmonellosis is multi-factorial. Trends are driven by both intrinsic factors relating to the microbiological quality of the food and standards of preparation, and extrinsic factors, such as ambient temperature, which amplify the intrinsic effects. Many of these factors may be amenable to preventive activities, including programs to reduce infection in animals and poultry and programs to educate the consumer in safe food handling.The costs of human salmonella infection in England and Wales were estimated to be between £231 million and £331 million in 1988 of which £143 million to £205 million may have been associated with meatborne infection. Reductions in human illness, as modelled by irradiation of poultry meat, could give substantial economic gains.