Initial Chilling Rate Effects on Bacterial Growth on Hot-Boned Beef ¹

We studied the chilling rate of hot-boned beef required to control bacterial growth during storage and display. Hot-boned cuts were chilled to 21 C by 3, 5, 9, and 12 h after their removal from the carcass. Cuts were vacuum-stored at 2.2 C for 14 or 21 d, then displayed at 2.2 C for 3 days under natural fluorescent lighting. Initial bacterial loads of hot-boned cuts were low (Log 0-3 CFU/cm²). Conventionally chilled beef (48 h at 2.2 C) and hot-boned cuts chilled to 21 C by 3, 5, and 9 h had lower bacterial counts and more desirable color and odor than hot-boned cuts chilled slower (12 h to 21 C). In general, indicator organisms and potential pathogens (coliforms, fecal coliforms, coagulase-positive Staphylococcus aureus , Clostridium perfringens , and fecal streptococci) were more numerous for cuts with slower chilling rates (9 and 12 h to 21 C) than for cuts chilled faster (3 and 5 h to 21 C and conventionally chilled beet). No Salmonella were detected. Hot-boned beef cuts are in good bacteriological condition (no potential health hazards) for storage if chilled to 21 C in 3 to 9 h.