Microbiological hazards and hygiene practices associated with meat from the deboning room of a grade a red meat abattoi

Abstract

In this study red meat samples were collected from a deboning room of a grade A abattoir. The samples were analysed for the presence of Bacillus cereus, Staphylococcus aureus, Pseudomonas spp., Listeria monocytogenes, Escherichia coli and Salmonella spp. The total plate counts as well as Enterobacteriaceae were also enumerated. The average B. cereus count over the sampling period was 8.32 x 103 du.g-1 , for S. aureus and Pseudomonasspp. 1.72 x 105 du.g-1 and 1.7 x 105 du.g-1 respectively and for E. coli 3.4 x 105 du.g-1 . Sixty percent of the samples were positive for presumptive Salmonella spp. while 52% of the samples tested positive for the presence of L. monocytogenes. The total plate and Enterobacteriaceae counts were 1.7 x 107 du.g-1 and 4.6 x 106 cfu.g-1 respectively. Almost without exception, the counts exceeded the microbiological guidelines for raw meat as proposed by the South African Department of Health. The interrelationships between the micro-organisms were also determined, and a strong correlation between the total plate counts and Enterobacteriaceae, Pseudomonas spp. and Staphylococcus aureus was respectively noted. Because deboning is such a labour and handling intensive process the practices, knowledge and attitudes of the meat handlers regarding personal and general hygiene were assessed by means of a structured questionnaire. The meat handlers were interviewed in their preferred language on aspects relating to personal and general hygiene appl ied in the deboning room. The results obtained indicated that a need exists for communication between management and workers as well as a need for more training in relation to personal and general hygiene. However, basic personal and hygiene practices such as the wearing of overalls and gumboots, as well as the cleaning and disinfection of equipment are applied, but need to be optimised in order to be effective.New approaches are being implemented to reduce the occurrence of food borne disease outbreaks. Risk assessment and HACCP are viewed as concepts that have become increasingly important in ensuring safe food upon consumption. In this study therefore, a stepwise identification procedure for food borne microbiological hazards was applied to evaluate pathogens associated with deboned vacuum-packaged red meat. The application of the hazard identification procedure resulted in the compilation of a pathogen list which included: B. cereus, S. aureus, presumptive Salmonella spp., L. monocytogenes, Clostridium botulinum and C perfringens. The list also included Pseudomonas spp., which are predominantly spoilage microorganisms. Finally a revised hazard identification flow sheet using information from both empirical data and literature was proposed.