MICROBIOLOGICAL EFFECTS OF ACID DECONTAMINATION OF PORK CARCASSES AT VARIOUS LOCATIONS IN PROCESSING

The microbiological effect of hot (55-degrees-C), 1% (v/v) lactic acid sprayed on the surface of pork carcasses (n = 36) immediately after dehairing, after evisceration (immediately before chilling) or at both locations in slaughter/processing was determined. Mean aerobic plate counts (APCs) of all acid-treated carcass surfaces were numerically lower than those of control carcasses; however, in most cases these reductions were not statistically significant (P > 0.05). All samples tested for the presence of Salmonella and Listeria were negative. No significant differences in sensory characteristics or microbiological counts were evident for acid-treated and control carcass loins that were vacuum packaged and stored 0-14 days post-fabrication. Mean pH value and scores of sensory attributes such as lean color, surface discoloration, fat color, overall appearance and off-odor of chops from acid-treated carcasses were not significantly and/or consistently different from chops of comparable control carcasses. The role of bacterial attachment to pork skin and its effect on the decontaminating efficiency of lactic acid are discussed.