Comparison of hot versus cold boning of beef carcasses on bacterial growth and the risk of blown pack spoilage

Primals were prepared from beef Longissimus thoracis et lumborum (LTL), psoas major (PM), quadriceps femoris (QF) and semitendinosus (S) muscles from cold and hot boned carcasses, vacuum-packaged and stored for 42 or 100 days at 2 °C and 7 °C. Storage temperature, carcass or primal surface temperature, pH and aw were monitored. Samples were taken periodically and tested for total viable count mesophilic (TVCm), TVC psychrophilic (TVCp), total Enterobacteriaceae count (TEC), presumptive Pseudomonas spp., lactic acid bacteria (LAB), Clostridium spp. and Brochothrix thermosphacta. A fifth muscle, biceps femoris (BF), was used to examine the impact of hot boning on blown pack spoilage (BPS). Primal counts increased to 6-7 log10 cfu cm− 2 after 6 weeks. Significantly (P < 0.05) higher TEC, Pseudomonas spp. and Br. thermosphacta counts were observed on cold versus hot boned primals. In contrast, significantly (P < 0.05) higher TVC, LAB and Clostridium spp. concentrations were obtained on hot boned beef. Moreover, BPS pack distension/bursting occurred considerably sooner in hot boned product.