Microbial Decontamination of Calf Carcasses by Lactic Acid Sprays

Six experiments were done with a total of 73 veal calves. Two pilot experiments were concerned to determine the maximal concentrations of lactic acid sprays that were acceptable in terms of fat cover color score and flavor score of lean Longissimus muscle. These pilot experiments indicated that concentrations up to 1.25% (vol/vol) of L-lactic acid did not produce unacceptable discoloration, and concentrations up to 2.00% (vol/vol) were not significantly different from controls in terms of flavor. In four additional experiments, the bactericidal properties of 1.25% L-lactic acid sprays were quantified. When measured 24 h postmortem, aerobic colony counts (3 d, 30°C) were reduced by 0.8 and 1.3 log₁₀ CFU/cm² on breast and perineum, respectively. Enterobacteriaceae counts, that were approximately 1.8 log₁₀ CFU/cm² initially, were reduced below their limit of detection (<1.3 log₁₀ CFU/cm²) as a result of lactic acid treatment. All tests for Salmonella were negative. Few, if any, Lactobacillaceae were isolated both in treatment and control groups.