EFFECT OF DEGREE OF SANITATION FROM SLAUGHTER THROUGH FABRICATION ON THE MICROBIOLOGICAL AND SENSORY CHARACTERISTICS OF BEEF

Steers were slaughtered, dressed, and fabricated using conventional procedures or strict sanitary procedures. Strict sanitary procedures involved antemortem washing of steers, use of disposable gloves, careful handling of carcasses to prevent cross-contamination, and spraying of carcasses with hot (55-degrees-C) 1% L-lactic acid before evisceration and before entering the chill cooler. Mean aerobic plate counts (APC, log10/cm2) of carcasses slaughtered under strict sanitary conditions and of subprimals (boneless strip loins and ribs) from animals handled under strict sanitary conditions and stored at 1-degrees-C in high-oxygen barrier (HOB) film (0 to 80 d) were lower than those of carcasses and subprimals from animals slaughtered and fabricated using conventional procedures. In most cases, APCs of steaks displayed in polyvinyl chloride (PVC) film for 0 to 6 d from animals and subprimals handled under strict conditions were lower than those of steaks from animals and subprimals handled under conventional procedures. Bacillus spp., Micrococcus spp., and yeasts were the dominant (50% or more of microflora) microbial types on carcasses that were slaughtered and dressed using strict sanitary conditions. For carcasses slaughtered using conventional procedures, Micrococcus spp. and to a lesser extent Streptococcus, coagulase-negative Staphylococcus and/or coryneform bacteria were the dominant microbial types. After 20 d of storage, there were no consistent differences in the percentage distribution of microbial types on the two groups of subprimals. Lactobacilli dominated the microflora of subprimals at that time. When scores for lean color, surface discoloration, fat color, overall appearance, and odor of steaks from subprimals handled under strict sanitary conditions were significantly different (P < 0.05) from controls, treated steaks were more desirable than those of comparable steaks from control subprimals.