A SURVEY OF MICROBIAL LEVELS FOR INCOMING RAW BEEF, ENVIRONMENTAL SOURCES, AND GROUND-BEEF IN A RED MEAT PROCESSING PLANT

A microbial survey was performed for a midwestern red meat processing plant that produces retail cuts and ground beef. Samples were obtained from incoming ingredients, beef during processing, finished product, food contact and environmental surfaces, and the air. Aerobic plate co unt (APC), coliform count (CC), and Escherichia coli count (ECC) were determined for each sample. Product samples (25 g) were taken from bee f carcasses, boxed beef, and ground beef. Swab samples (10 cm(2)) were obtained from food surfaces, food contact surfaces, floors, and walls . All samples were plated on aerobic plate count Petrifilm (for APC) a nd E. coil Petrifilm (for CC and ECC). Average log(10) APC for product samples ranged from 3 cfu g(-1) for retail cuts to nearly 7 cfu g(-1) for boxed beef and the brisket and flank areas of beef carcasses. Ave rage log(10) APC for ground beef samples was 4.6 cfu g(-1). Average lo g(10) CC for product samples ranged from 1.4-2.3 cfu g(-1). Highest CC was usually obtained from the brisket area of the beef carcass. Avera ge log(10) ECC ranged from < 1-2 cfu g(-1) and ECC was usually highest in finished ground beef. Average surface counts for log(10) APC range d from < 1 cfu cm(2) on sanitized processing equipment to 5 cfu cm(-2) on processing floors. Coliforms and E. coli were rarely recovered fro m food contact surfaces or from food surfaces. Airborne log(10) APC wa s generally low (0.6 cfu m(-3)) except for the carcass receiving area where counts were 2.4 cfu m(-3). The most important factor contributin g to source and level of microbial contamination for ground beef and r etail cuts was from incoming raw materials obtained from different sup pliers of beef. Microbial testing for beef products and the environmen t is an important fool for identifying and monitoring potential hazard s as part of HACCP and GMP program development. (C) 1997 Academic Pres s Limited.