|Cason Jr, John|
Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 28, 2001
Publication Date: N/A
Interpretive Summary: Clostridium perfringens is a cause of bacterial food-borne disease in man which is often associated with consumption of poultry products. Previous studies conducted thirty years ago demonstrated that C. perfringens occurs in the poultry processing plant. Since procedures and equipment in the processing plant have changed, this study was conducted to determine the current status of contamination of representative broiler chicken processing plants with cells of this pathogen. In addition, for the first time, levels of contamination with C. perfringens heat- resistant spores were determined because the spore form survives cooking procedures used in food preparation, a factor contributing to most food-borne disease outbreaks involving C. perfringens. C. perfringens was isolated from the water of the scald tank and chill tank in the processing plant and from the processed chicken carcasses. Numbers of this organism decreased from the beginning to the end of processing and were low on the processed carcass. A high proportion of contamination was in the form of heat-resistant spores. The incidence of C. perfringens on processed carcasses ranged from 0 to 67% depending on the processing plant and flock being processed. In conclusion, commercially processed chicken remains a potential source for food-borne disease caused by this pathogen if the processed product is not prepared properly by the consumer.
Technical Abstract: Processing procedures have changed since Clostridium perfringens (Cp) was reported to contaminate the processing plant and the processed carcasses of broiler chickens (Lillard, 1971). Therefore, a study was conducted to determine the incidence and numbers of Cp in processing plant samples. Of three pre-selected broiler chicken flocks from two integrators, the incidence of Cp associated with the three flocks was 40% of post-processing scald water samples, 13% of pre- and post- processing chill water samples and 19% of carcass rinses. In Trial 2, samples from each tank of a three-tank counterflow scalder, from the pre-chill and chill tanks and from carcasses were collected in the middle of a processing shift of a processing plant. The incidence of Cp was 100% of water samples from scald tank 1, 100% from scald tank 2, 100 % from scald tank 3, 88% from the pre-chill tank, 63% from the chill tank, and 67% of carcass rinse samples. The mean MPN of Cp for contaminated samples decreased from log10 5.1/100 ml of water in scald tank 1 to log10 1.3/100 ml in the chill tank. The mean MPN in carcass rinse samples was log10 1.2/100ml. The incidence and mean MPN of Cp in samples after heat shock indicated that much of the contamination arises from heat-resistant spores of this organism.