- Email: [email protected]
Salmonella prevalence in beef lymph nodes and feces from cattle harvested at five Mexican abattoirs
Abstracts
105 Evaluation of process control to prevent contamination of beef with non-O157 Shiga toxin-producing Escherichia coli (STEC) in U.S. export abattoirs in Honduras and Nicaragua B.D. Chaves, M. Maradiaga, M.A. Calle, L. Thompson, S.P. Jackson, T. Jackson, M.F. Miller, L.G. Garcia, A. Echeverry⁎, H. Ruiz, M.M. Brashears, Texas Tech University, Lubbock, United States Objectives: The objectives of this project were to determine 1) the prevalence of non-O157 STEC on beef hides and carcasses in export abattoirs in Honduras (Plant A) and Nicaragua (Plant B) and 2) if current practices and interventions controlled final carcass contamination. Materials and methods: Samples were collected on the foreshanks from the hides, at pre-evisceration, and after application of an antimicrobial treatment (2–2.5% lactic acid spray). A PCR protocol was used to assess the presence of S. enterica and STEC serogroups O26, O45, O103, O111, O121, O145, and O157. In Plant A, 30 swabs were collected at each point for a total of 90 samples corresponding to 30 animals. Similarly, 50 swabs were collected at each point in Plant B for a total of 150, corresponding to 50 animals. An FSISapproved PCR protocol was used to assess the presence of STEC serogroups O26, O45, O103, O111, O121, and O145 using the Dupond Qualicon BAX® system. Results: In Plant A, 23.3% (7/30) of hides contained at least one STEC serogroup, whereas in Plant B, 90.0% (45/50) tested positive. Preevisceration samples had a prevalence of 6.7% (2/30) for Plant A and of 0% for Plant B. No STEC were detected after antimicrobial intervention. Serogroups O26, O45, and O121 were the most prevalent in plant A with frequencies of 27/75 (36.0%), 24/75 (32.0%), and 18/75 (24.0%), respectively. In Plant B, O26 and O121 were predominant with 47.5% (38/80) and 46.3% (37/80), respectively. Conclusion: The results of this study indicate that STEC were present on the hides but current hygienic practices and interventions effectively controlled them and reduced final carcass contamination. This information will serve to these companies as evidence of adequate process control. Keywords: Abattoir, Honduras, Nicaragua, Non-O157 STEC, Process control doi:10.1016/j.meatsci.2013.07.143
106 Inhibition of foodborne pathogens in “no nitrate- or nitrite-added” bacon brine and bacon A.G. Mckeitha,⁎, E.W. Millsb, C.N. Cutterc, K.B. Kephartb, aAgriculture, Western Kentucky University, Bowling Green, United States, bAnimal Sciences, Pennsylvania State University, University Park, United States, c Food Science, Pennsylvania State University, University Park, United States Objectives: Processed meats manufactured using natural curing ingredients may exhibit color, flavor and shelf-life attributes similar to traditional products. However, few reports describe the effects of natural curing ingredients on survival and growth of foodborne pathogens in meat products. Therefore, the objective of this study was to evaluate the inactivation of vegetative Clostridium perfringens (CP), Listeria monocytogenes (LM), Escherichia coli O157:H7 (EC) and Salmonella Typhimurium (ST) inoculated in bacon brine formulations using natural nitrate (vegetable juice powder, Symrise, Teterboro, NJ) with starter culture (CS-299 Bactoferm, Chr Hansen, Inc., Milwaukee, WI), natural nitrite with a natural cure accelerator (celery baste and cherry baste aid, Newly Weds, Chicago, IL), and traditional cure (sodium nitrite and sodium erythorbate). Materials and methods: All cure ingredients were utilized at the concentrations recommended by the manufacturers and sodium nitrite
489
and sodium erythorbate were used at concentrations approved by the United States Department of Agriculture. In all instances, salt and sugar were added to 20% and 5% of brine formulation, respectively. Three replications with two quarter bellies per replication per treatment were utilized to evaluate the inhibition of foodborne pathogens of “no nitrate- or nitrite-added” bacon. Bellies were inoculated with a cocktail of the four foodborne pathogens (initial inoculation ~8 log10 CFU/mL for each pathogen), injected with respective brine treatments (10% target pump), and cooked to an internal temperature of 53 °C. Following approximately 24 h of chilling, bellies were sliced and vacuumpackaged. Individual, refrigerated sliced bacon samples were taken at 0, 1, 3, 7, 14, and 21 days after inoculation and evaluated for remaining bacterial populations on selective agars for each pathogen evaluated. Enumeration of pathogens was done using direct plating and/or enrichment procedures for each pathogen. Results: The pH of each brine was different (P b 0.05) from each other with the natural nitrate brine having the lowest pH (4.01) and the natural nitrite having the highest pH (7.48). The no cure had a pH of 4.81 and the traditional cure had a pH of 5.58. However, once the brine was inoculated into the belly they quickly buffered to near neutral (pH ~ 6.8). There were no differences (P N 0.05) among the treatments for aerobic bacteria, coliforms, and generic E. coli. Inoculated bellies treated with natural nitrate, natural nitrite, traditional cure, and no cure exhibited growth (~7 log10 CFU/g) of LM, EC, and ST (P N 0.05). Traditional cure was more effective at inhibiting CP than all other treatments, regardless of day of storage (P b 0.05). Conclusion: Traditional cure was the only treatment that resulted in no growth of CP. The information from this study can be utilized by the USDA or processed meat manufacturers when making their decision about the usage of “natural curing” ingredients in cured meat products. Keywords: Bacon, Foodborne pathogens, Nitrite doi:10.1016/j.meatsci.2013.07.144
107 Salmonella prevalence in beef lymph nodes and feces from cattle harvested at five Mexican abattoirs H. Ruiz⁎, M.F. Miller, S. Gragg, G.H. Loneragan, L.G. Garcia, M.M. Brashears, Animal and Food Science, Texas Tech University, Lubbock, United States Objectives: The objective of this study was to determine the prevalence by city and the overall prevalence of Salmonella isolated from LNs and feces collected from cattle at harvest in five Mexican harvest facilities in Veracruz, Merida, Cualta, Cancun and Playa del Carmen, Mexico. Materials and methods: From each carcass, one lymph node from the following; mandibular (MAN), mediastinal (MENS, mesenteric (MES) and subiliac (SUB) was collected (n = 1056) and feces (FE) was also collected from the same carcasses (n = 267). LN samples were enriched using tryptic soy broth (TSB), subjected to immunomagnetic separation (IMS) and streaked on Xylose Lysine Desoxycholate (XLD) agar and Brilliant Green Sulfa (BGA) and final confirmation for Salmonella with latex agglutination. Feces samples were enriched using a primary enrichment of Buffered Peptone Water (BPW), and secondary enrichments of Rappaport–Vassiliadis Broth (RV) and Tetrathionate Broth (TT) and were streaked using selective media Xylose Lysine Tergitol-4 (XLT-4) and typical colonies where selected and agglutinated. Results: For the city of Veracruz, prevalence was as follows: 49.15%, 4.23%, 63.55%, 67.79%, and 77.11% for MAN LN, MENS LN, MES LN, SUB LN and FE, respectively. Merida prevalence was as follows: 23.00%, 19.67%, 40.87%, 8.51%, and 55.44% for MAN LN, MENS LN, MES LN, SUB LN and FE, respectively. Cualta prevalence
490
Abstracts
was as follows: 30.00%, 20.00%, 10.00%, 0.00%, and 40.00% for MAN LN, MENS LN, MES LN, SUB LN and FE, respectively. Cancun prevalence was as follows: 18.75%, 0.00%, 37.5%, 12.50%, and 81.25% for MAN LN, MENS LN, MES LN, SUB LN and FE, respectively. Playa Del Carmen prevalence was as follows: 50.00%, 12.50%, 62.50%, 12.5%, and 50.00% for MAN LN, MENS LN, MES LN, SUB LN and FE, respectively. Lastly, overall prevalence was 35.47%, 9.38% 49.48%, 36.99% and 66.40% for MAN LN, MENS LN, MES LN, SUB LN and FE, respectively. Conclusion: Results suggest that Salmonella is commonly harbored in cattle lymph nodes throughout the body with certain lymph nodes having higher prevalence of Salmonella. Also, results suggest that anatomical location may play a role in variation of prevalence with Mesenteric lymph nodes having the highest overall prevalence; Mediastinal lymph nodes had the lowest prevalence. These findings should be further investigated to better understand potential infection pathways, mode of action, opportunities for Salmonella control in ground beef products and eventually a resolution to Salmonella infection in beef lymph nodes.
participants indicated having existing food defense plans prior to the workshops while 84% indicated intent to implement and/or make changes to their plan. Seventy-five percent had an increased knowledge of food defense, biosecurity, and traceability after workshop completion. Individual scores improved up to 42%. Conclusion: Many of the areas and points of an operation may often be overlooked or taken for granted under normal day to day activities by employees which can jeopardize the overall food safety and security. Through effective food defense training and education, farmers and food manufacturers including distributors and suppliers will be able to better assess all vulnerable points to develop a defense plan that is best suited for their operation. Whether problems arise from intentional or unintentional means, farmers and food manufacturers need to be prepared to respond quickly and efficiently to problems that arise. Through these workshops 117 members of the food industry chain now have a better understanding of food defense and are better prepared to continue and increase the overall safety of our food supply. Keywords: Food defense, Food producers, Meat/poultry processors, Traceability
Keywords: Beef, Feces, Lymph node, Salmonella doi:10.1016/j.meatsci.2013.07.145
doi:10.1016/j.meatsci.2013.07.146
Meat Science Education and Extension Tools
Muscle and Lipid Biology and Biochemistry
108 Producer and processor knowledge enhancement of food defense and traceability as a result of training J.B. Williams⁎, A.F. Hood, E.L. Griswold, Food Science, Nutrition, and Health Promotion, Mississippi State University, MS, United States
109 Differential abundance of sarcoplasmic proteome in beef inside and outside semimembranosus muscle S.P. Sumana,⁎, M.N. Naira, M.K. Chatlia,b, S. Lia, P. Josepha,c, C.M. Beacha, G. Rentfrowa, aUniversity of Kentucky, Lexington, United States, b Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana, India, cKalsec, Inc., Kalamazoo, United States
Objectives: Agriculture and food are global industries, and any attack on these would be felt worldwide. There are numerous points of vulnerability within the food chain for intentional and unintentional contamination which jeopardize the overall safety and biosecurity of our food supply. Intentional as well as unintentional threats and attacks can occur in various ways: biological, physical, radiological, chemical or nuclear. USDA has enhanced efforts recently to encourage all meat, poultry and egg processing operations to have viable Food Defense Plans in place by 2015. With a target of 90% voluntary compliance by 2015, the small and very small plants are currently well behind the stated target which could lead to mandatory compliance. With passage of the Food Safety Modernization Act of 2011 and the recent publication of guidelines for compliance requirements for produce and other human food from FDA, food defense and hazard assessments will be mandatory for producers and processors of foods under FDA regulation. The objective of this research and subsequent training sessions was to promote awareness and educate all types of food producers and food manufacturers on the principles of food defense, biosecurity and traceability of agricultural commodities and ingredients used in human food production. For those operations with existing plans, the intent was to further advance training and knowledge to their sector of the industry. Materials and methods: Food defense and traceability plans evaluate all areas of a business and infrastructure including: personnel, incoming ingredients/pesticides/feed, supplies, supply transportation, processing, finished product transportation, and product tracking. Training was conducted through seminars, workshops, supplementary materials, and checklists. Pre-tests and post-tests were administered to determine knowledge base and improvement. Results: Preliminary investigations indicated that most small and very small operations were unprepared for such incidents and threats. Eight training sessions were conducted at various locations with a total of 117 participants made up of meat and poultry processors (44) and various other food commodity producers (73). Fifty-four percent of
Objectives: Beef semimembranosus muscle has distinct colorstable outside (OSM) and color-labile inside (ISM) regions. The differential color stability between OSM and ISM has been partly attributed to the variations in temperature and pH decline during carcass chilling. Nonetheless, the underlying molecular mechanisms are not completely understood. Differential abundance of sarcoplasmic proteome influences color stability of beef muscles. However, the proteome basis for intra-muscular variations in the color stability of beef semimembranosus is yet to be investigated. Therefore, our objective was to characterize the sarcoplasmic proteome of beef OSM and ISM. Materials and methods: Eight (n = 8) beef inside rounds (48 h post-mortem; IMPS # 168) were procured from a commercial packaging plant. The semimembranosus muscles were separated and fabricated into ISM and OSM. Samples for proteome analyses were collected and frozen at − 80 °C. Sarcoplasmic proteome was extracted from each sample and subjected to two-dimensional gel electrophoresis in duplicate. Gels were stained, and the images were analyzed. Protein spots exhibiting differential abundance (P b 0.05) were subjected to tryptic digestion and were identified using tandem mass spectrometry. Results: Beta-enolase, fructose-bisphosphate aldolase A, phosphoglycerate mutase, and phosphatidylethanolamine-binding protein 1 were over-abundant in ISM, whereas triose phosphate isomerase and creatine kinase M-type were over-abundant in OSM. Beta-enolase, fructose-bisphosphate aldolase A, and phosphoglycerate mutase are enzymes critically involved in glycolysis. Conclusion: The over-abundance of three glycolytic enzymes in color-labile ISM suggests the possibility that a rapid post-mortem pH decline associated with high glycolytic activity could accelerate myoglobin oxidation, compromise the metmyoglobin reduction system, and thus potentially contribute to discoloration.
105 Evaluation of process control to prevent contamination of beef with non-O157 Shiga toxin-producing Escherichia coli (STEC) in U.S. export abattoirs in Honduras and Nicaragua B.D. Chaves, M. Maradiaga, M.A. Calle, L. Thompson, S.P. Jackson, T. Jackson, M.F. Miller, L.G. Garcia, A. Echeverry⁎, H. Ruiz, M.M. Brashears, Texas Tech University, Lubbock, United States Objectives: The objectives of this project were to determine 1) the prevalence of non-O157 STEC on beef hides and carcasses in export abattoirs in Honduras (Plant A) and Nicaragua (Plant B) and 2) if current practices and interventions controlled final carcass contamination. Materials and methods: Samples were collected on the foreshanks from the hides, at pre-evisceration, and after application of an antimicrobial treatment (2–2.5% lactic acid spray). A PCR protocol was used to assess the presence of S. enterica and STEC serogroups O26, O45, O103, O111, O121, O145, and O157. In Plant A, 30 swabs were collected at each point for a total of 90 samples corresponding to 30 animals. Similarly, 50 swabs were collected at each point in Plant B for a total of 150, corresponding to 50 animals. An FSISapproved PCR protocol was used to assess the presence of STEC serogroups O26, O45, O103, O111, O121, and O145 using the Dupond Qualicon BAX® system. Results: In Plant A, 23.3% (7/30) of hides contained at least one STEC serogroup, whereas in Plant B, 90.0% (45/50) tested positive. Preevisceration samples had a prevalence of 6.7% (2/30) for Plant A and of 0% for Plant B. No STEC were detected after antimicrobial intervention. Serogroups O26, O45, and O121 were the most prevalent in plant A with frequencies of 27/75 (36.0%), 24/75 (32.0%), and 18/75 (24.0%), respectively. In Plant B, O26 and O121 were predominant with 47.5% (38/80) and 46.3% (37/80), respectively. Conclusion: The results of this study indicate that STEC were present on the hides but current hygienic practices and interventions effectively controlled them and reduced final carcass contamination. This information will serve to these companies as evidence of adequate process control. Keywords: Abattoir, Honduras, Nicaragua, Non-O157 STEC, Process control doi:10.1016/j.meatsci.2013.07.143
106 Inhibition of foodborne pathogens in “no nitrate- or nitrite-added” bacon brine and bacon A.G. Mckeitha,⁎, E.W. Millsb, C.N. Cutterc, K.B. Kephartb, aAgriculture, Western Kentucky University, Bowling Green, United States, bAnimal Sciences, Pennsylvania State University, University Park, United States, c Food Science, Pennsylvania State University, University Park, United States Objectives: Processed meats manufactured using natural curing ingredients may exhibit color, flavor and shelf-life attributes similar to traditional products. However, few reports describe the effects of natural curing ingredients on survival and growth of foodborne pathogens in meat products. Therefore, the objective of this study was to evaluate the inactivation of vegetative Clostridium perfringens (CP), Listeria monocytogenes (LM), Escherichia coli O157:H7 (EC) and Salmonella Typhimurium (ST) inoculated in bacon brine formulations using natural nitrate (vegetable juice powder, Symrise, Teterboro, NJ) with starter culture (CS-299 Bactoferm, Chr Hansen, Inc., Milwaukee, WI), natural nitrite with a natural cure accelerator (celery baste and cherry baste aid, Newly Weds, Chicago, IL), and traditional cure (sodium nitrite and sodium erythorbate). Materials and methods: All cure ingredients were utilized at the concentrations recommended by the manufacturers and sodium nitrite
489
and sodium erythorbate were used at concentrations approved by the United States Department of Agriculture. In all instances, salt and sugar were added to 20% and 5% of brine formulation, respectively. Three replications with two quarter bellies per replication per treatment were utilized to evaluate the inhibition of foodborne pathogens of “no nitrate- or nitrite-added” bacon. Bellies were inoculated with a cocktail of the four foodborne pathogens (initial inoculation ~8 log10 CFU/mL for each pathogen), injected with respective brine treatments (10% target pump), and cooked to an internal temperature of 53 °C. Following approximately 24 h of chilling, bellies were sliced and vacuumpackaged. Individual, refrigerated sliced bacon samples were taken at 0, 1, 3, 7, 14, and 21 days after inoculation and evaluated for remaining bacterial populations on selective agars for each pathogen evaluated. Enumeration of pathogens was done using direct plating and/or enrichment procedures for each pathogen. Results: The pH of each brine was different (P b 0.05) from each other with the natural nitrate brine having the lowest pH (4.01) and the natural nitrite having the highest pH (7.48). The no cure had a pH of 4.81 and the traditional cure had a pH of 5.58. However, once the brine was inoculated into the belly they quickly buffered to near neutral (pH ~ 6.8). There were no differences (P N 0.05) among the treatments for aerobic bacteria, coliforms, and generic E. coli. Inoculated bellies treated with natural nitrate, natural nitrite, traditional cure, and no cure exhibited growth (~7 log10 CFU/g) of LM, EC, and ST (P N 0.05). Traditional cure was more effective at inhibiting CP than all other treatments, regardless of day of storage (P b 0.05). Conclusion: Traditional cure was the only treatment that resulted in no growth of CP. The information from this study can be utilized by the USDA or processed meat manufacturers when making their decision about the usage of “natural curing” ingredients in cured meat products. Keywords: Bacon, Foodborne pathogens, Nitrite doi:10.1016/j.meatsci.2013.07.144
107 Salmonella prevalence in beef lymph nodes and feces from cattle harvested at five Mexican abattoirs H. Ruiz⁎, M.F. Miller, S. Gragg, G.H. Loneragan, L.G. Garcia, M.M. Brashears, Animal and Food Science, Texas Tech University, Lubbock, United States Objectives: The objective of this study was to determine the prevalence by city and the overall prevalence of Salmonella isolated from LNs and feces collected from cattle at harvest in five Mexican harvest facilities in Veracruz, Merida, Cualta, Cancun and Playa del Carmen, Mexico. Materials and methods: From each carcass, one lymph node from the following; mandibular (MAN), mediastinal (MENS, mesenteric (MES) and subiliac (SUB) was collected (n = 1056) and feces (FE) was also collected from the same carcasses (n = 267). LN samples were enriched using tryptic soy broth (TSB), subjected to immunomagnetic separation (IMS) and streaked on Xylose Lysine Desoxycholate (XLD) agar and Brilliant Green Sulfa (BGA) and final confirmation for Salmonella with latex agglutination. Feces samples were enriched using a primary enrichment of Buffered Peptone Water (BPW), and secondary enrichments of Rappaport–Vassiliadis Broth (RV) and Tetrathionate Broth (TT) and were streaked using selective media Xylose Lysine Tergitol-4 (XLT-4) and typical colonies where selected and agglutinated. Results: For the city of Veracruz, prevalence was as follows: 49.15%, 4.23%, 63.55%, 67.79%, and 77.11% for MAN LN, MENS LN, MES LN, SUB LN and FE, respectively. Merida prevalence was as follows: 23.00%, 19.67%, 40.87%, 8.51%, and 55.44% for MAN LN, MENS LN, MES LN, SUB LN and FE, respectively. Cualta prevalence
490
Abstracts
was as follows: 30.00%, 20.00%, 10.00%, 0.00%, and 40.00% for MAN LN, MENS LN, MES LN, SUB LN and FE, respectively. Cancun prevalence was as follows: 18.75%, 0.00%, 37.5%, 12.50%, and 81.25% for MAN LN, MENS LN, MES LN, SUB LN and FE, respectively. Playa Del Carmen prevalence was as follows: 50.00%, 12.50%, 62.50%, 12.5%, and 50.00% for MAN LN, MENS LN, MES LN, SUB LN and FE, respectively. Lastly, overall prevalence was 35.47%, 9.38% 49.48%, 36.99% and 66.40% for MAN LN, MENS LN, MES LN, SUB LN and FE, respectively. Conclusion: Results suggest that Salmonella is commonly harbored in cattle lymph nodes throughout the body with certain lymph nodes having higher prevalence of Salmonella. Also, results suggest that anatomical location may play a role in variation of prevalence with Mesenteric lymph nodes having the highest overall prevalence; Mediastinal lymph nodes had the lowest prevalence. These findings should be further investigated to better understand potential infection pathways, mode of action, opportunities for Salmonella control in ground beef products and eventually a resolution to Salmonella infection in beef lymph nodes.
participants indicated having existing food defense plans prior to the workshops while 84% indicated intent to implement and/or make changes to their plan. Seventy-five percent had an increased knowledge of food defense, biosecurity, and traceability after workshop completion. Individual scores improved up to 42%. Conclusion: Many of the areas and points of an operation may often be overlooked or taken for granted under normal day to day activities by employees which can jeopardize the overall food safety and security. Through effective food defense training and education, farmers and food manufacturers including distributors and suppliers will be able to better assess all vulnerable points to develop a defense plan that is best suited for their operation. Whether problems arise from intentional or unintentional means, farmers and food manufacturers need to be prepared to respond quickly and efficiently to problems that arise. Through these workshops 117 members of the food industry chain now have a better understanding of food defense and are better prepared to continue and increase the overall safety of our food supply. Keywords: Food defense, Food producers, Meat/poultry processors, Traceability
Keywords: Beef, Feces, Lymph node, Salmonella doi:10.1016/j.meatsci.2013.07.145
doi:10.1016/j.meatsci.2013.07.146
Meat Science Education and Extension Tools
Muscle and Lipid Biology and Biochemistry
108 Producer and processor knowledge enhancement of food defense and traceability as a result of training J.B. Williams⁎, A.F. Hood, E.L. Griswold, Food Science, Nutrition, and Health Promotion, Mississippi State University, MS, United States
109 Differential abundance of sarcoplasmic proteome in beef inside and outside semimembranosus muscle S.P. Sumana,⁎, M.N. Naira, M.K. Chatlia,b, S. Lia, P. Josepha,c, C.M. Beacha, G. Rentfrowa, aUniversity of Kentucky, Lexington, United States, b Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana, India, cKalsec, Inc., Kalamazoo, United States
Objectives: Agriculture and food are global industries, and any attack on these would be felt worldwide. There are numerous points of vulnerability within the food chain for intentional and unintentional contamination which jeopardize the overall safety and biosecurity of our food supply. Intentional as well as unintentional threats and attacks can occur in various ways: biological, physical, radiological, chemical or nuclear. USDA has enhanced efforts recently to encourage all meat, poultry and egg processing operations to have viable Food Defense Plans in place by 2015. With a target of 90% voluntary compliance by 2015, the small and very small plants are currently well behind the stated target which could lead to mandatory compliance. With passage of the Food Safety Modernization Act of 2011 and the recent publication of guidelines for compliance requirements for produce and other human food from FDA, food defense and hazard assessments will be mandatory for producers and processors of foods under FDA regulation. The objective of this research and subsequent training sessions was to promote awareness and educate all types of food producers and food manufacturers on the principles of food defense, biosecurity and traceability of agricultural commodities and ingredients used in human food production. For those operations with existing plans, the intent was to further advance training and knowledge to their sector of the industry. Materials and methods: Food defense and traceability plans evaluate all areas of a business and infrastructure including: personnel, incoming ingredients/pesticides/feed, supplies, supply transportation, processing, finished product transportation, and product tracking. Training was conducted through seminars, workshops, supplementary materials, and checklists. Pre-tests and post-tests were administered to determine knowledge base and improvement. Results: Preliminary investigations indicated that most small and very small operations were unprepared for such incidents and threats. Eight training sessions were conducted at various locations with a total of 117 participants made up of meat and poultry processors (44) and various other food commodity producers (73). Fifty-four percent of
Objectives: Beef semimembranosus muscle has distinct colorstable outside (OSM) and color-labile inside (ISM) regions. The differential color stability between OSM and ISM has been partly attributed to the variations in temperature and pH decline during carcass chilling. Nonetheless, the underlying molecular mechanisms are not completely understood. Differential abundance of sarcoplasmic proteome influences color stability of beef muscles. However, the proteome basis for intra-muscular variations in the color stability of beef semimembranosus is yet to be investigated. Therefore, our objective was to characterize the sarcoplasmic proteome of beef OSM and ISM. Materials and methods: Eight (n = 8) beef inside rounds (48 h post-mortem; IMPS # 168) were procured from a commercial packaging plant. The semimembranosus muscles were separated and fabricated into ISM and OSM. Samples for proteome analyses were collected and frozen at − 80 °C. Sarcoplasmic proteome was extracted from each sample and subjected to two-dimensional gel electrophoresis in duplicate. Gels were stained, and the images were analyzed. Protein spots exhibiting differential abundance (P b 0.05) were subjected to tryptic digestion and were identified using tandem mass spectrometry. Results: Beta-enolase, fructose-bisphosphate aldolase A, phosphoglycerate mutase, and phosphatidylethanolamine-binding protein 1 were over-abundant in ISM, whereas triose phosphate isomerase and creatine kinase M-type were over-abundant in OSM. Beta-enolase, fructose-bisphosphate aldolase A, and phosphoglycerate mutase are enzymes critically involved in glycolysis. Conclusion: The over-abundance of three glycolytic enzymes in color-labile ISM suggests the possibility that a rapid post-mortem pH decline associated with high glycolytic activity could accelerate myoglobin oxidation, compromise the metmyoglobin reduction system, and thus potentially contribute to discoloration.