Mixed Meat Research Articles

Determination of carnosine in Black-Bone Silky Fowl (Gallus gallus domesticus Brisson) and common chicken by HPLC

Black-Bone Silky Fowl (Gallus gallus domesticus Brisson) is both consumed as a healthy food and used particularly as a kind of traditional Chinese medicine. Carnosine in the muscles of Black-Bone Silky Fowl was identified by HPLC–MS/PAD. The carnosine content in the meat of Black-Bone Silky Fowl was determined by HPLC and compared with that contained in the meat of White Plymouth Rock, which were bred under the same condition. The results showed that the contents of carnosine in the mixed meat, breast meat and thigh meat of Black-Bone Silky Fowl were all remarkably higher than that in the White Plymouth Rock. These findings indicate that Black-Bone Silky Fowl would be a better chicken breed for carnosine supplement.

P127: Sources of Dietary Fats among Yup'ik Eskimos

Current national recommendations suggest keeping fat intake between 20- 35% of energy intake, in part because high fat diets are associated with high saturated fat intake. The traditional diet of Alaska Natives, however, exceeds this acceptable macronutrient distribution range, the impact of which is poorly understood. We sought to identify the leading sources of fat among Yup'ik Eskimos living in remote communities in Alaska to better understand potential health implications. A 24-hour recall was collected from 237 male and 310 females aged 14-94 years. Percent energy from fat was positively associated with age (P < .01) but not sex. The leading sources of fat differed by age group, although some similarities were observed. Among 14-19 year olds mixed meat dishes, which included burritos, pizza, corndogs, chili and hamburgers, accounted for 17% of total fat intake. Fish and seal oil contributed 24% and 35% of total fat among 20-49 year olds and 50+ year olds, respectively. Although no difference in total saturated fat intake was observed between age groups, both mono and polyunsaturated fatty acid intake increased with age (P < .01). This suggests that the higher fat intake observed in the older participants may be accounted for by higher mono and polyunsaturated fatty acid intake and not saturated fat. These findings suggest that national recommendations developed for the general public may not be appropriate among Alaska Natives consuming a traditional diet. Support for the project was provided by the NIH grant (P20-RR16430).

Criteria of consumers when purchasing beef in retail stores: Position of beef compared to other meat types, reasons and frequency of its use in everyday nutrition and preparation methods

Information was collected by conducting poll of the town residents (N=478) in which their attitude towards the traits of beef quality, as well as their habits and inclinations in regard to the choice of category, retail cuts and giblets were analyzed. Also, the position of beef compared to other meat types was studied, reasons and frequency of meat consumption in every day nutrition and preparation methods. Data were further analyzed according to sex, age and occupation of participants in the poll in order to come to conclusion about their effect on the meat selection criteria. Female consumers consume beef (17,7%) more than mutton (6,7%), and less than pork (39,0 %) and poultry meat (36,5%). Compared to them, male consumers consume more pork (41,8%), beef (26,0 %) and mutton (9,2 %) and less poultry meat (23,0 %). When choosing the category of beef, 67,7% of consumers selected young beef, 28,6% veal and only 3,7% beef. Approx. 50% of consumers declared that the first thing when selecting meat category is their inclination, followed by quality, price or recommendation by doctor. However, consumers with higher education, as well as female and younger consumers prefer meat with lower fat content. Visual impression when choosing young beef in retail stores is most important for average consumer. Approx. 43% of participants in the poll stated color of meat as decisive factor, red-pink color is desired. Second factor when choosing beef is presence of fatty tissue more appreciated by male and older consumers which find it more tasteful. Young beef is most often consumed once a week (60%), mainly cooked, in soups or stews, with special inclination of male consumers towards smoked beef. Consumers mainly buy breasts and ribs (40%), and rarely beef steaks (2,5%), in other words dishes containing beef with bones are most often prepared, as well as dishes containing mixed ground meat. The use of giblets is rare, especially among female population, liver, hearts and beef stomach (so called "skembic") and tongue are mainly used.

Levels of polychlorinated biphenyls (PCBs) in meat and meat products from the state of Rio Grande do Sul, Brazil

The levels of six polychlorinated biphenyl congeners (PCBs) were evaluated in 55 samples of meat (bovine and pork) and meat products (sausage, hot dog sausage, bologna sausage, canned export meat and salami) from 11 cities of the state of Rio Grande do Sul, Brazil, between July and August 2002. PCB congeners were found (in fat basis) in the following rank 52 (5.18 ng/g) > 180 (1.69 ng/g) > 10 (1.35 ng/g) > 28 (1.19 ng/g) > 153 (0.47 ng/g) > 138 (0.43 ng/g), with a ∑PCB amounting to 10.30 ng/g. Meat products had higher PCB levels than meat. PCB levels in samples followed the rank: mixed meat products > pork meat > bovine meat. These results indicate the presence of PCBs in food samples from Rio Grande do Sul, Brazil, but the levels found were well below the maximum level established for animal food products in Brazil (3000 ng/g fat). Only one sample exceeded the maximum level established by the European Community (200 ng/g fat). This is the first paper describing background concentrations of PCBs in meat and meat products from Brazil.

The effect of heat treatment on the cholesterol oxides, cholesterol, total lipid and fatty acid contents of processed meat products

The effects of heat treatment on the formation of cholesterol oxides and on alterations of fatty acid composition were investigated in processed meat products. Meatballs (beef), hamburger (beef and Chester), sausage (pork, chicken and Chester) and frankfurter (mixed meat, chicken and Chester) were analysed. There was no cholesterol oxide formation caused by heat treatment of the samples analysed. The fatty acid compositions, calculated as g/100 g sample, showed alterations only between the raw and grilled beef hamburger. Only the cholesterol levels were significantly changed when comparing the raw and grilled pork sausages and the raw and grilled Chester hamburger, the values being lower in the grilled samples. Also, the total lipid contents of grilled beef hamburgers were lower than the values.

Prevalence of Listeria monocytogenes in 13 dried sausage processing plants and their products

The aims of the present study were: (i) to investigate the occurrence of Listeria monocytogenes in dried sausage processing plants on surfaces before and during processing, (ii) to study the contamination in meat and sausages at different stages of maturation, (iii) to assess the distribution of L. monocytogenes in the different plants and products studied. Thirteen dried sausage processing plants were sampled at two different times of the working day. The studies were repeated twice to evaluate the persistence of the pathogen. A total of 1029 samples were collected. Among swabbed samples, 15% were positive before the beginning of the working day and 47.3% during working day. Results showed that effectiveness of cleaning and disinfecting operations could be linked with the complexity of processing lines and machines used. The presence of L. monocytogenes in mixed meat amounted to 71.6% of the collected samples. A decrease of the contamination rate in dry sausage was noted, particularly during the drying stage. Nevertheless 3 sausages studied presented a low contamination rate (<3 cfu/g) when ready for consumption. A total of 996 strains of L. monocytogenes were characterised by biochemical tests and serotyping. A majority of isolates were 1/2a (49.5%), 1/2c (19.5%) and 1/2b (13%) strains. A high heterogeneity of serotypes was observed in all plants, raw meat and in sausages during maturation.

Total selenium concentrations in canine and feline foods commercially available in New Zealand

AIMS: To determine the total selenium concentrations in petfoods commercially available in New Zealand and to establish whether these meet the current minimum recommended requirements of selenium in foods for cats and dogs. METHODS: Samples (n=89) from petfoods commercially available in New Zealand were analysed for total selenium concentration using a fluorometric method. Data, expressed on a dry matter (DM) basis, were analysed according to petfood type (dog or cat, and wet or dry), predominant flavour (chicken, seafood, chicken and seafood, beef, meat mix, other), manufacturer and country of manufacture. RESULTS: Fifty percent of petfoods purchased for this study were manufactured in Australia, and the remainder were produced in the United States of America (USA), New Zealand or Thailand. Mean total selenium concentrations were similar (0.61–0.80 mg/kg DM) in petfoods produced in Australia, New Zealand and the USA, but higher (mean 3.77 mg/kg DM; p<0.05) in petfoods produced in Thailand. Petfoods produced in Australia, New Zealand and the USA contained a variety of predominant flavours, whereas petfoods from Thailand contained only seafood flavour. Seafood-based flavours had the highest selenium concentrations in both cat and dog foods. Wet and dry dog foods had similar concentrations of selenium to dry cat foods, but wet cat foods had higher and more variable concentrations of selenium than these others (p<0.05). The mean selenium concentrations in cat and dog foods were 1.14 and 0.40 mg/kg DM, respectively, and there were no significant differences between manufacturers. CONCLUSIONS: Selenium concentrations in commercial petfoods sold in New Zealand appeared to meet recommended dietary requirements, although the range of concentrations was highly variable. Whether these recommendations are adequate for the maintenance of optimal health in cats and dogs has yet to be determined. CLINICAL RELEVANCE: Overt selenium deficiency disorders are unlikely in dogs and cats in New Zealand fed commercial petfoods unless the bioavailability of selenium in particular petfoods is low.

Immunoassay Kit Used to Detect the Presence of Bovine Material in Processed Foods

The Tepnel Bio Kit for the detection of beef in cooked foods was assessed to determine its validity in demonstrating if food being imported into New Zealand contains beef material. The test suffered no interference from the presence of other common nonbovine species meats accepted as food within New Zealand and it detected beef in cooked samples of mixed meats when the proportion of beef in the mixture was >2 or >1%, depending on other meat species present. The documentation supplied with the kit indicates that the specific proteins it measures in cooked beef are stable to 130 degrees C. This was confirmed in the literature when the kit was used to test meat and bone meal cooked to at least 133 degrees C. However, our results showed these proteins to be much less stable when heated to elevated temperatures in moist food under pressure, and samples containing beef ceased to be positive by the immunoassay test after being autoclaved to 121 degrees C. This suggests that the test may not be able to detect even relatively high levels of beef in low-acid canned foods, which are normally retorted under pressure to approximately 121 degrees C.

Changes in food group consumption patterns from childhood to young adulthood: The Bogalusa Heart Study

Objective The objective of this study was to assess changes in food group consumption patterns from childhood to young adulthood. Design Twenty-four-hour dietary recalls were collected on a longitudinal sample of young adults. Subjects/Setting Dietary intake data were collected on 246 young adults (70% European American, 30% African American) aged 19 to 28 years who participated in a previous cross-sectional survey when they were 10-year-olds. Statistical analyses Descriptive statistics and linear mixed models adjusting for study time (age), sex, and ethnicity. Results In childhood, consumption of fruits/fruit juice and mixed meats ( P≤.05), desserts, candy, and milk ( P≤.0001) were greater than in young adulthood. Young adulthood consumption was greater for sweetened beverages, poultry and seafood ( P≤.001), salty snacks ( P≤.05), and beef ( P≤.01) compared to childhood. Milk consumption decreased, but the decrease was greater among males ( P≤.0001). Sweetened beverage consumption increased, but the increase was greater for European Americans ( P≤.0001). Candy consumption decreased, but the decrease was greater for African Americans ( P≤.05). Conclusions Changes occur in food group consumption patterns from childhood to young adulthood. Overall, there was a decrease in diet quality during this age transition. Understanding eating habits of children early in life is important for planning effective intervention strategies.

Children’s food consumption patterns have changed over two decades (1973–1994): the Bogalusa heart study

Objective To evaluate types of foods and amounts consumed by 10-year-old children during the period from 1973 to 1994. Design One 24-hour dietary recall was collected on each child who participated in one of seven separate cross-sectional surveys of 10-year-olds. Subjects/Setting Dietary intake data was collected on 1,584 10-year-old children (65% Euro American, 35% African American), in Bogalusa, LA, from 1973 to 1994 using SAS 8.0 (1999, SAS Institute Inc, Cary, NC). Statistical analyses performed Data were analyzed to calculate descriptive statistics. Pearson’s χ 2 test was used for testing equality of percentage of each food group consumed across the seven surveys. Cochran-Armitage trend test and general linear models were used to test for trends, adjusting for total energy intake, ethnicity, and sex. Results The percentage of children consuming, and the mean gram amount consumed, significantly decreased for fats/oils ( P<.0001), desserts ( P<.0001), candy ( P<.0001), eggs ( P<.001), and milk ( P<.0001). In contrast, the percentage of children consuming, and the mean gram amount consumed, significantly increased for fruits/fruit juices ( P<.01), mixed meats ( P<.01), poultry ( P<.0001), and cheese ( P<.0001). Despite a significant decrease in the percentage of children consuming vegetables ( P<.01) and beef ( P<.01), the mean gram amount consumed did not change. The percentage of children consuming breads/grains, pork, and snacks did not change, but the mean gram amount of salty snacks ( P<.001) significantly increased and the amount of breads/grains ( P<.01) and pork ( P<.01) significantly decreased. The percentage of children consuming sweetened beverages ( P<.01) and condiments ( P<.001) decreased while the mean gram amount consumed increased ( P<.05) and ( P<.0001). The mean gram amount of lunch and dinner consumed increased ( P<.0001) but snacks decreased ( P<.0001), resulting in no change in total gram amount consumed in a 24-hour period. Conclusions Trends in food consumption patterns of children should be considered in the design and implementation of population-based behavior strategies for the promotion of health and prevention of chronic diseases beginning in childhood.

Eating patterns and obesity in children: The Bogalusa Heart Study

Background Childhood obesity is a growing public health problem. This study examined the association between eating patterns and overweight status in children who participated in the Bogalusa Heart Study. Methods A single 24-hour dietary recall was collected on a cross-sectional sample of 1562 children aged 10 years (65% Euro-American [EA], 35% African American [AA]) over a 21-year period. Overweight was defined as body mass index greater than the 85th percentile using Centers for Disease Control and Prevention reference standards. Multivariate logistic regression was used to investigate the association between eating patterns and overweight. Results Consumption of sweetened beverages (58% soft drinks, 20% fruit flavor drinks, 19% tea, and 3% coffee) ( p<0.001); sweets (desserts, candy, and sweetened beverages) ( p<0.001); meats (mixed meats, poultry, seafood, eggs, pork, and beef) ( p<0.051); and total consumption of low-quality foods ( p<0.01) were positively associated with overweight status. Total amount of food consumed, specifically from snacks, was positively associated with overweight status ( p<0.05). There was a lack of congruency in the types of eating patterns associated with overweight status across four ethnic–gender groups. The percent variance explained from the eating pattern–overweight models was very small. The interaction of ethnicity and gender was significantly associated with overweight status ( p<0.001). The odds of being overweight for EA males were 1.2 times higher than for AA females. Conclusions These results demonstrate that numerous eating patterns were associated with overweight status, yet the odds of being overweight were very small. Additional studies are needed to confirm these findings in a longitudinal sample having multiple days of assessment.

Effect of Enrobing and Adding Antioxidants on the Quality of Pork Patties

The effect of applying edible coating and addition of antioxidants (butylated hydroxyanisole (BHA) plus butylated hydroxytoluene (BHT) in a 1:1 ratio) on pork patties were investigated prior to achieve desired physico-chemical, microbiological and sensory qualities. For this, five treatments were conducted as (i) control (neither coated nor antioxidants treated); (ii) coated without antioxidants treated; (iii) coated and antioxidants added in the batter mix only (100 ppm); (iv) coated and antioxidants added in meat mix (100 ppm) only; and (v) coated and antioxidants added both in the batter mix (50 ppm) and the meat mix (50 ppm). Addition of antioxidants both in the batter mix and the meat mix significantly (p<0.05) reduced the microbial loads and thiobarbituric acid (TBA) values. The TBA values significantly (p<0.05) increased up to day 14 and then progressively increased with the advancement of each interval of storage days up to 28 days. Total plate count significantly (p<0.05) increased with the increase in storage days.Coliform and Staphylococcus aureus were absent throughout the storage days in all samples. Staphylococcus aureus however, were present in the control group at day 14 and in enrobed (coated) patties (without antioxidants treated) at 28th day. Addition of antioxidants to batter mix and meat mix did not substantially enhance bacteriostatic activity. Application of coatings and antioxidants retarded the loss of firmness, flavor, changes in appearance and color, and also other sensory attributes. Control patties were better with respect to microbial quality and TBA values but had poorer sensory quality than coated patties.

Evaluation of a novel enrichment procedure for the isolation of Escherichia coli O157 from naturally contaminated raw beef, lamb and mixed meat products

The aim of this study was to compare enrichment at 41·5°C for 24 h in a prototype enrichment broth developed by Oxoid, UK (sTSB), with enrichment at 37°C for 6 h in buffered peptone water supplemented with vancomycin, cefixime and cefsulodin (BPW-VCC) for isolation of Escherichia coli O157 from naturally contaminated raw beef, lamb and mixed meat products.A total of 120 meat samples from previous surveillance studies, 91 of which were previously positive and 29 previously negative for E. coli O157, were used for the study. All had been stored at −70°C for between 19 and 58 months since first examination. Of the 91 previously positive samples, 67 were positive after enrichment in sTSB and 42 were positive after enrichment in BPW-VCC;E.coli O157 was not recovered from 20 previously positive samples by either method. Of the 29 previously negative samples, three were positive by enrichment in sTSB and two were positive by enrichment in BPW-VCC;E.coli O157 was not recovered from 25 previously negative samples by either method.Of the 71 isolates obtained from the meat samples, only 53 had the same toxin genotype and plasmid profile as the E.coli O157 isolated from the sample originally. On four occasions, the strain isolated originally, the strain isolated from re-culture in BPW-VCC and the strain isolated from sTSB were all different. The only feasible explanation for these differences is that two or more different strains of E.coli O157 were present in the original sample. Results of strain typing ofE.coli O157 isolated from food samples, particularly during an outbreak investigation, should therefore be interpreted with caution.

Comparison of culture, PCR and immunoassays for detecting Escherichia coli O157 following enrichment culture and immunomagnetic separation performed on naturally contaminated raw meat products

The aims of this study were (i) to evaluate the specificity and sensitivity of three previously described PCR assays for the detection of Escherichia coli O157 and, (ii) to compare PCR, culture, and two visual immunoassays (VIAs), BioSign™ and Path-Stik™, for detecting E. coli O157 after enrichment culture and immunomagnetic separation (IMS) performed on various naturally contaminated raw beef, lamb and mixed meat products. Twelve sorbitol nonfermenting (SNF) verocytotoxin-producing (VT+) E. coli O157, 6 SNF VT− E. coli O157, 4 sorbitol fermenting (SF) VT+ E. coli O157, 3 SF VT− E. coli O157, 23 E. coli belonging to 17 other serogroups and 12 organisms of other species were used to check the specificity of PCR reactions. Only one primer pair generated amplimers only with E. coli O157 and was used for all subsequent work. After enrichment culture and on inoculated minced beef samples, PCR was as sensitive as culture for detecting 9 of the 12 strains of E. coli O157, but up to 4 log 10 more sensitive than culture for detecting three strains. Of the 120 samples of naturally contaminated meat products examined, 80 (67%) were positive by PCR, 70 (58%) were positive by BioSign™, 69 (58%) were positive by culture and 67 (56%) were positive by Path-Stik™. Although both VIAs lacked sensitivity when compared to PCR, both compared favourably with culture and both were extremely rapid and easy to perform, giving a result in less than 15 min. Eleven samples were positive by PCR and both VIAs, but negative by culture because culture plates were heavily overgrown with SF organisms, making detection of any E. coli O157 present impossible.

Trends in nutrient intake of 10-year-old children over two decades (1973-1994) : the Bogalusa Heart Study.

Dietary intakes of 10-year-old children were examined in seven cross-sectional surveys to observe secular trends in nutrient intake and food consumption patterns over 2 decades (1973-1994). Total energy intake remained unchanged from 1973 to 1994. However, when expressed as energy per kilogram body weight, intake decreased from 65.5 kcal in 1973 to 55.4 kcal in 1994 because children's weight increased. A significant trend was noted in ponderal index, which increased from 12.31 (1973-1974) to 13.71 (1992-1994), with an actual weight gain of 1.45 kg from 1973 to 1979 and 2.71 kg from 1981 to 1994. Linear trends also were noted for total fat (negative), saturated fat (negative), dietary cholesterol (negative), polyunsaturated fat (positive), and total carbohydrate (positive). There was a significant increase in percent energy from protein and carbohydrate and a significant decrease in percent energy from fat, primarily saturated and monounsaturated fat. Trends in nutrient intakes of children reflected trends in food consumption. The percentage of total fat from fats/oils, mixed meats, eggs, milk, pork, and desserts decreased, while that from poultry, cheese, and snacks increased. Although more children met dietary recommendations for total fat, saturated fat, and dietary cholesterol, the vast majority continued to exceed prudent diet recommendations.

Time budget, foraging activities, diet and occurrence of aspergillosis in captive yellowheads (Mohoua ochrocephala)

Instantaneous and focal animal sampling were used to describe various activities and foraging methods of eight captive yellowheads. They spent, on average, 74% of their time foraging, and most often foraged on the ground. Gleaning was the most frequently employed feeding method. The birds’ diet consisted of a proprietory insectivore meat mix, a variety of arthropods and miscellaneous foods. Nectar consumption was observed in this species for the first time. The study has implications for the prevention of avian aspergillosis in captive birds.

Replacement of fish meal in diets for Australian silver perch, Bidyanus bidyanus: III. Digestibility and growth using meat meal products

Apparent digestibility and availability coefficients for beef and bone meal, lamb and bone meal, a high protein meal from mixed species (mixed meat meal, reduced ash, no bones) and from Provine®, a high protein meal based on selected ingredients, were determined for juvenile silver perch. Experimental diets comprised a reference diet plus meat meal products at either 15% or 30% inclusion. Silver perch readily accepted diets with up to 30% meat meal. Digestibility coefficients for dry matter, energy, protein, and availability coefficients for amino acids were determined to assist with the formulation of diets to assess growth of silver perch. Digestibility coefficients for dry matter, energy, and protein all increased with increasing protein content in the meat products. Average amino acid availability coefficients were highest for the mixed meat meal and Provine®. Availability coefficients for alanine, arginine, glycine, methionine, proline and serine were all significantly higher for these products than for either beef or lamb meal. Availability of sulphur amino acids was significantly lower in Provine® than in other products. Compared with fish meal, all meat products contained less lysine and some meat products were also low in phenylalanine, isoleucine, and histidine. An increase in total protein content, through removal of bone, improved the nutritional value of meat meal in silver perch diets. Juvenile silver perch were grown for 65 days in 10 000-l tanks, using one of five diets with similar digestible nitrogen, energy, and dry matter but different contents of fish meal, lamb meal, and Provine®. Fish growth was reduced when diets contained less than 13% fish meal and more than 9% Provine®. However, feed conversion efficiency and protein retention efficiency (PRE) were unaffected by diet formulation. These results indicate that meat meal can replace most of the fish meal in silver perch diets without reducing fish performance.

Trends in Nutrient Intake of 10-Year-Old Children From 1973-1994: The Bogalusa Heart Study

Twenty-four hour dietary recalls were obtained from 7 cohorts of 10 year-old-children (35% black, 65% white; N=1465) over a 21 year period. Secular trends in energy, macronutrient, cholesterol, and fatty acid intakes were compared with dietary recommendations and trends in food consumption patterns. Total energy intake was virtually the same over the study period (2054-2224 kcal); boys had higher intakes than girls. There was a negative trend for energy intake relative to body weight (65.5+28.6 [SD] to 55.4+26.1; p<.0001) due to increases in absolute weight. Linear trends over time were observed for total fat (93. l[gm] ±46.5 to 84.6+40.4; p< 003); saturated fat (38.2 [gm]+18.9 to 29.7+16.0; p< 0001); unsaturated fat (49.1 [gm]+26.2 to 42.3±22.9; p<.0001); and cholesterol (324[mg]+219 to 246+181; p<.0001). There was a significant increase in percent energy from protein (13.0+3.4 to 13.9+3.8; p<.001) and carbohydrate (49.4+ 9.5 to 51.3+9.2; p<.002); and a significant decrease in percent energy from fat (38.4+7.9 to 35.8+8.0; p< 0001), primarily saturated (15.9+3.5 to!2.5+4.0; p<.0001) and monounsaturated (14.1+4.3 to 11.9+3.0; p<.0001) fats. Trends in nutrient intake are consistent with trends in types of foods consumed by children. The percentage of fat from mixed meats, poultry, breads, and grains has increased. Despite improvement in intake of children, 80%, 70%, and 73% exceeded the recommended intake for total fat, saturated fat, and dietary cholesterol, respectively. Data suggest that there is an ongoing need for continued monitoring of dietary intakes and health promotion efforts for US children.

Free and bound fatty acid oxidation products in archaeological ceramic vessels

While oxidation products of unsaturated fatty acids, for example dicarboxylic acids (hereafter diacids), must form during the use of unglazed ceramic vessels for the processing of animal and plant products, such components have never been observed during studies of absorbed lipids. Their absence from the extractable lipid fraction is presumed to be the result of their loss from potsherds through groundwater leaching. Lipid oxidation products including short-chain dicarboxylic acids, ω-hydroxy acids and longer-chain hydroxy and dihydroxy acids have now been observed as components probably covalently bound into solvent insoluble residues of potsherds recovered from waterlogged deposits. These components were only revealed following alkaline treatment of the insoluble residues. A similar mixture of diacids was observed in high abundance in the free lipid fraction of vessels recovered from an exceptionally arid deposit where groundwater leaching would never have occurred. These results confirm the formation of oxidation and probable polymerization products of unsaturated fatty acids during vessel use and burial.

Preservation of Vacuum-Packaged Pork Liver Paté by Fermentation.

Fermentation with Lactobacillus plantarum and Pediococcus cerevisiae was evaluated as a natural method of preservation for use in pork liver paté. Addition of both starter strains to a raw meat mix (108 CFU g-1) lowered the pH to 4.0 in 15 h at 30°C. Subsequent cooking to a core temperature of 70°C followed by vacuum packaging resulted in a product which remained acceptable for longer than 22 days when stored at 4°C and 10°C. Addition of glucose did not increase the activity of the lactic acid starter organisms, indicating the presence of endogenous fermentable substrate in the raw ingredients. Challenge test studies employing Staphylococcus aureus , Salmonella infantis , and Clostridium sporogenes were carried out in finished product at 37°C. No recovery was observed 7 days postinoculation. Results from this investigation indicate the potential use of lactic acid starter cultures to obtain a microbiologically stable product with enhanced safety.