LOW-DOSE GAMMA-IRRADIATION AND REFRIGERATED STORAGE IN-VACUO AFFECT MICROBIAL-FLORA OF FRESH PORK

Vacuum-packaged ground fresh pork samples absorbed gamma radiation dos es of 0, 0.57, 1.91, 3.76, 5.52, or 7.25 kGy at 2-degrees-C. Samples w ere analyzed after 1, 7, 14, 21, 28, or 35 days storage at 2-degrees-C for presence and number of aerobic and anaerobic mesophiles and endos pore formers, and aerobic psychrotrophs. Conventional plate counts did not detect surviving microflora in any sample that received an absorb ed dose of 1.91 kGy or higher, even after refrigerated storage for up to 35 days. The microflora in the control were predominantly Gram-posi tive for the first 21 days; however, Serratia predominated at 28 and 3 5 days. Staphylococcus, Micrococcus, and yeast species predominated in samples that received 0.57 kGy.