Bacteriological Quality of Meat and Public Health
Dr.Kedar Karki
Background:
Developing countries are faced with a high incidence of food poisoning outbreaks related to the consumption of meat, with obvious economic consequences. During informal slaughter of animals the threat of food poisoning or transfer of lethal zoonoses such as anthrax, is particularly intense. The prime objective of a meat hygiene and safety programme is the assurance of wholesomeness and the supply of quality meat sold to the consumer. The presence of a meat inspection system examines grossly apparent abnormalities during the ante-mortem and post mortem examination, but does not recognize complex microbial contamination, which could later precipitate major public health hazards and economic loss in terms of food poisoning and spoilage of meat .Surface contamination of carcasses during slaughter and processing can be reduced by ensuring good manufacturing practices such as hygiene and sanitation of the floor, equipment, and carcasses, with suitable disinfectants and sanitizers. To enable risks involved to be estimated and appropriate measures to be taken, analysis of the slaughtering process has to be complemented by collection of abattoir-specific microbiological monitoring data, in accordance with hazard analysis critical control point (HACCP) principles. A regular microbiological examination of carcasses allows reliable conclusions to be drawn with regard to long-term hygienic conditions in abattoirs.
Sources of food contamination
Sources of food contamination may be primary, coming directly from an infected food animal or its secretions, or excretions; or secondary, resulting from contamination in handling of food.
Primary contamination
A food animal may be slaughtered while it is either infected with a microbial pathogen or contaminated with chemical or other residues. In some instances, this presents an occupational hazard to stockyard or abattoir workers, but more often it poses a threat to the consumer. Ante-mortem inspection reveals only a small percentage of these cases.
Secondary contamination
Secondary infection may come from infected humans or live-animal carriers of pathogens, soil, equipment, excreta and hands, nasal discharges, contaminated wounds, contaminated water, insects or feed additives. Infected humans may be the source of contamination at any point in the food chain but are most frequently implicated when preparing food for the table.
All fresh meat becomes contaminated with microorganisms during the slaughter and dressing process, some of these bacteria may include pathogens which are food poisoning microorganisms. Microbiological testing forms part of HACCP implementation. Testing should be used to investigate microbiological effects of the operations within, or affecting, any process, in order to validate the procedure adopted for controlling microbiological contamination of products. Microbiological testing for HACCP must involve the enumerator and indicator organism.
Indicator organisms
Indicator organisms are a group of bacteria that are indicative for the possible presence of organisms of concern, such as pathogens. They are used in assessment of the overall quality of a food and hygiene conditions present during processing. Indicator organisms include: total aerobic counts, coli forms, Enterobacteriaceae, generic E.coli, fecal and streptocoi.This will indicate how much clean, hygienic and healthy environment is there in slaughter places.
