Extent of Microbial Contamination in United States Pork Retail Products

Abstract

To determine the extent of microbiological contamination of U.S. pork, 384 samples of retail pork were collected from 24 stores in six cities, including (i) whole-muscle, store-packaged pork; (ii) fresh, store-packaged ground pork and/or pork sausage; (iii) prepackaged ground pork and/or pork sausage; and (iv) whole-muscle, enhanced (injected or marinated; 60% store-packaged, 40% prepackaged) pork. Additional samples (n = 120) of freshly ground pork and/or pork sausage were collected from two hot-boning sow/boar sausage plants, two slaughter and fabrication plants, and two further-processing plants. Samples were analyzed for aerobic plate counts (APC), total coliform counts (TCC), Escherichia coli counts (ECC), and incidences of Salmonella spp., Listeria monocytogenes, Campylobacter jejuni, Campylobacter coli, and Yersinia enterocolitica. Mean log APC and TCC were highest (P < 0.05) for store-ground pork, while whole-muscle, enhanced products and prepackaged ground products had the lowest (P < 0.05) APC. Mean log APC and TCC were higher (P < 0.05) in samples from the slaughter and fabrication plants than in samples from hot-boning and further processing plants. Mean log ECC were lower (P < 0.05) in samples from further-processing plants compared to slaughter and fabrication plants and hot-boning, sow and boar sausage plants. L. monocytogenes was detected in 26.7% of plant samples and 19.8% of retail samples and was present more frequently in ground products. Y. enterocolitica was detected most often in whole-muscle, store-packaged cuts (19.8%) and in store-ground product (11.5%). Salmonella spp. were found in 9.6% of retail samples and 5.8% of plant samples, while C. jejuni and C. coli were found in 1.3% of retail samples and 6.7% of plant samples. Pork products exposed to the most handling and processing appeared to be of the poorest microbiological quality. These results should be useful in risk assessments that are directed at the identification of actions that could enhance food safety.

Prevalence, Enumeration, Serotypes, and Antimicrobial Resistance Phenotypes of Salmonella enterica Isolates from Carcasses at Two Large United States Pork Processing Plants

“…There were six pork-related Salmonella outbreaks in the United States during 2007 that resulted in 208 illnesses and 24 hospitalizations (14,18). Studies on the prevalence of Salmonella in U.S. retail pork products are very limited, and results vary from "less than 2%" in one study (66) to 9.6% in another (27). The prevalence of Salmonella on carcasses in the United States after chilling (chilled final) examined between 2001 and 2009 ranged between 2 and 4% according to the annual reports of the Food Safety and Inspection Service (FSIS) testing of U.S. slaughter establishments (33).…”

Use of Pulsed-Field Gel Electrophoresis To Characterize the Heterogeneity and Clonality ofSalmonellaIsolates Obtained from the Carcasses and Feces of Swine at Slaughter

“…Pork products may be particularly risky, since two recent studies detected Salmonella spp. in 10 and 16% of raw retail pork products (10,26). Contamination of pork products by Salmonella is often the result of feces being spread onto carcasses during the slaughter and processing of swine.…”

Microbiological hazards at several stages of production and distribution of cooked sausages

“…in sausage pastes (Table 1), is the result of the frequent presence of these microorganisms in raw meat (Bell and Kyriakidis 1998, Chart et al 2000, Duffy et al 2001, Genigeorgis 1987, Limpitakis et al 1999. The presence of many other foodborne pathogens, including Cambylobacter spp (Duffy et al 2001), and Yersinia enterocolytica (Bottone 1997, Duffy et al 2001) has been reported also. This fact practically makes us consider all pastes as positive for foodborne pathogens and therefore they must be handled properly in order to prevent any potential contamination of cooked sausages as well as the areas where they are stored, sliced and packaged.…”

“…Ο πληθυσμός των κολοβακτηριοειδών ή ταν > 2.400 MPN/g τόσο στο κολλαγόνο όσο και στις κρε-ατόπαστες, ενώ διαπιστώθηκε και η παρουσία της E. coli σε όλα τα δείγματα. ΣΥΖΗΤΗΣΗ Η παρουσία των L. monocytogenes, E. coli και Salmo nella spp στις κρεατόπαστες (Πίνακας 1) είναι αποτέλε σμα της υψηλής συχνότητας μόλυνσης του κρέατος με τους μικροοργανισμούς αυτούς (Bell and Kyriakidis 1998, Chart et al 2000, Duffy et al 2001, Genigeorgis et al 1989, Limpitakis et al 1999, Letellier et al 1999.…”

“…Έχει επίσης αναφερθεί η παρουσία και άλλων ειδών όπως Campylobacter spp (Duffy et al 2001), Yersinia enterocolitica (Bottone 1997, Duffy et al 2001, Letellier et al 1999, τα οποία αποτελούν επίσης αίτια πρόκλησης τροφιμογενών λοιμώξεων.…”