MICROBIOLOGICAL QUALITY OF BEEF CARCASSES AND VACUUM-PACKAGED SUBPRIMALS - PROCESS INTERVENTION DURING SLAUGHTER AND FABRICATION

Beef carcass sides (n = 9 per replicate) were sprayed with water (W), 200 ppm chlorine (C), or 3% (vol/vol) lactic acid (L) immediately after rail inspection and at the end of an 8-h spray-chill cycle, resulting in a total of nine different spray combinations. All treatment combinations involving chlorine and/or lactic acid reduced carcass contamination. The reductions in mean log(10) CFU/cm(2) for carcass aerobic plate count (APC) data ranged from 0.4 to 1.8. The treatment combination using lactic acid at both spray times (Let) resulted in the greatest reduction. Additionally, treatment combinations involving lactic acid at either time and in combination with water or chlorine tended to reduce APCs more than those treatment combinations without acid. Browning of blood splashes was observed on carcasses sprayed with lactic acid and persisted until fabrication at 72 h postmortem. A companion study was designed, in conjunction with the carcass decontamination study, to evaluate effect of carcass treatment on the microbiological quality of subprimal subdivisions derived from treated carcasses. A facet of the subprimal study evaluated chlorine spray (200 ppm) and microwave radiation as approaches to improving subprimal shelf life and safety. Cuts taken from sprayed carcasses were vacuum packaged with or without intervention treatments, stored at 1 to 2 degrees C and evaluated for both APC and pathogen populations at specified intervals of up to 120 days. These results demonstrated that neither carcass nor intervention treatment had any significant (P > 0.05), beneficial effect on the microbiological quality of subprimal cuts.