Changes in the microflora on commercial beef trimmings during their collection, distribution and preparation for retail sale as ground beef.

A commercial process for ground meat production, from the collection of meat plant trimmings to the retailing of consumer packs of ground beef, was examined. The selected process compiled with current concepts of Good Manufacturing Practice. During storage for up to 18 days before grinding, most trimming developed a flora of lactobacilli, of up to 10(7) CFU/g. Numbers of coliforms and of Escherichia coli on stored trimmings increased little and not at all, respectively. Increased total counts, and numbers of both coliforms and E. coli in displayed product indicated loss of control of the temperature of the displayed packaged product. It appears that the need to store a product, taking into account the unpredictable fluctuations in supply and demand, will inevitably result in much ground beef carrying large numbers of spoilage bacteria. Furthermore, currently accepted Good Practice in the retail handling of ground beef does not adequately control either spoilage or the growth of pathogenic bacteria.