MICROBIOLOGICAL AND SENSORY ATTRIBUTES OF RETAIL CUTS OF BEEF TREATEDWITH ACETIC AND LACTIC-ACID SOLUTIONS

This research characterized the effect of 0.6 and 1.2% acetic and lact ic acids applied for 20 and 120 s at a temperature of 1 to 2 degrees C on total colony forming units (CFU) and Escherichia coli counts, and sensory qualities including shear value, expressible moisture, color a nd sensory panel of retail cuts of beef rib steaks. Microbial inhibiti on was directly proportional to the concentration and times of treatme nt with a 1.2% acid treatment for 120 s being the most effective treat ment for reducing microbial counts, for both acids. Although there wer e significant reductions (p <0.05) in bacterial populations, these red uctions which had a maximum of 2.0 log, were of questionable practical significance. The inhibitory effect of the acids decreased with stora ge time, up to 9 days. Treatment with both the acids resulted in paler meat (p <0.05) than the non-treated control. There were no significan t differences (p >0.05) in shear values or expressible moisture due to acid treatment. Sensory panels reported only small differences betwee n the samples. These results indicate that an aqueous acetic or lactic acid treatment of retail beef reduced total CFU and E. coli numbers i mmediately after treatment, but the magnitude was less than 1 log. How ever, a residual influence was observed so that after 3 and 9 days bot h acid treatments inhibited total CFU and E. coli growth by up to 2 lo gs compared with the non-treated control samples.