Microbiological Safety of Retail Vacuum-Packed and Modified-Atmosphere-Packed Cooked Meats at End of Shelf Life

Abstract

A study of retail modified-atmosphere-packed and vacuum-packed cooked ready-to-eat meats was undertaken from September through mid-November 2003 to determine the microbiological quality at the end of shelf life and to establish any risk factors in the production, storage, and display of this product. Examination of 2,981 samples using Microbiological Guidelines criteria revealed that 66% were of satisfactory or acceptable microbiology quality, 33% were of unsatisfactory quality mainly due to high aerobic colony counts and Enterobacteriaceae concentrations, and 1% were of unacceptable quality due to the presence of Listeria monocytogenes at 100 CFU/g or higher (27 samples; range of 10(2) to 106 CFU/g) and Campylobacter jejuni (1 sample), indicating a risk to health. All samples at the end of the shelf life had satisfactory (<20 CFU/g) and/or acceptable (<102 CFU/g) levels of Staphylococcus aureus and Clostridium perfringens, four samples (<1%) had unsatisfactory levels of Escherichia coli (range of 102 to 106 CFU/g) and 5.5% of the samples contained L. monocytogenes at <20 CFU/g (4.8%) or between 20 and 100 CFU/g (0.7%). More samples of chicken (45%; 224 of 495 samples), beef (43%; 160 of 371 samples), and turkey (41%; 219 of 523 samples) were of unsatisfactory or unacceptable quality compared with ham (23%; 317 of 1,351 samples) or pork (32%; 67 of 206 samples). Twelve different L. monocytogenes typing characters (serotype-amplified fragment length polymorphism type-phage type) were evaluated for isolates recovered from samples of unacceptable quality, and the 1/2-IX-NT type was recovered from almost half (48%) of these samples. Salmonella was not detected in any samples examined. Risk factors identified for cooked meats that were microbiologically contaminated more frequently included vacuum packaging, packaging on retail premises, slicing, temperature not monitored in display units, and no hazard analysis system in place. Results from this study also suggest that the shelf life assigned to some modified-atmosphere-packed and vacuum-packed meats may not be appropriate.

Deteriorating Inventory Model for Chilled Food

“…exceed the 7 logCFU/g, most meat products will be inedible [30,42,[52][53][54][55][56][57]; we can set to be equal to 7− ( )/7; hence the value of will decrease if ( ) increases.…”

The Effect of Washing of Carcasses with Sodium Hypochlorite Solution and Vacuum Packaging on the Microbiological and Physiochemical Quality of the Breast Meat from Old Hen during Storage at 4℃

“…일반적으로 총 호기성 미생물 증식이 7 Log CFU/g 수준이면 식품이 부패한 것으로 판단 (Sagoo et al, 2007;Mbarki et al, 2009 (Egan et al, 1981;Ohashi et al, 1991 (Kweon et al, 1995). Dahl(1957) …”

Request for updating the former SCVPH opinion on Listeria monocytogenes risk related to ready-to-eat foods and scientific advice on different levels of Listeria monocytogenes in ready-to-eat foods and the related risk for human illness - Scientific Opinio

“…Parameters associated with the presence of the bacterium include food packaging type, preparation practices (e.g. the use of slicing machines for meat products), storage temperatures, the stage of sampling with respect to shelf life, the lack of an effective HACCP system, and the lack of education and training of food handlers (Lewis et al, 2006;Lianou and Sofos, 2007;Little et al, 2007;Sagoo et al, 2007).…”