Assessment of the hygienic characteristics of a process for dressing pasteurized pig carcasses

The hygienic characteristics of a process for dressing pasteurized pig carcasses were assessed. Initially, a randomly selected site on each of 25 randomly selected carcasses leaving the process was sampled by swabbing an area of approximately 100 cm(2). Total aerobic counts, coliforms and Escherichia coli were enumerated in each sample, to identify sites which yielded relatively high log(10) total (>2 cm(-2)), coliform (>1 100 cm(-2)) and/or E. coli (>1 100 cm(-2)) counts. The dressing process was inspected to provisionally associate each heavily contaminated site with an operation in the process. Then the hygienic effects of the selected operations were examined by sampling an appropriate site on each of 25 randomly selected carcasses entering and 25 leaving the operation, and when the site might be affected by a previous operation, by sampling the same site on 25 carcasses entering the process. Carcasses were heavily contaminated with coliforms and E. coli as a result of the operation involving opening of the throat and the floor of the mouth and the operation involving the withdrawal of the anus and a length of the rectum from the body cavity. The small (about 10%) fractions of E. coli in the coliforms recovered from most sites indicated that most of the E. coli on dressed carcasses originated from the mouth rather than the anus, on which most coliforms were E. coli. The two operations associated with heavy E. coli contamination can be regarded as the critical control points in a hazard analysis: critical control point (HACCP) system for the process. Those operations, and others that resulted in the deposition on carcasses of relatively heavy loads of bacteria but of few E. coli can be regarded as quality control points in a quality management (QM) system where storage stability is amongst the qualities to be assured. (C) 1997 Academic Press Limited.