USE OF NISIN AND MICROWAVE TREATMENT REDUCES CLOSTRIDIUM-SPOROGENES OUTGROWTH IN PRECOOKED VACUUM-PACKAGED BEEF

Nisin (NS), microwave (MW), and nisin plus microwave (NS + MW) treatme nts were applied to precooked beef semitendinosus muscles inoculated w ith spores of Clostridium sporogenes. Samples were then vacuum package d and stored at 4 degrees C or 10 degrees C for 21 or 70 days. After 2 1 days of storage at 10 degrees C, NS and NS + MW reduced viable veget ative cell (VVC) counts by approximately 3 log cycles compared to the control. After 70 days storage, WC counts were higher (P < 0.05) at 10 degrees C than 4 degrees C only for the control. However, at 4 degree s C, WC counts for each treatment were not different (P > 0.05) from t hose of the control. After 70 days of storage at 10 degrees C, WC coun ts were lower (P < 0.05) for NS and NS + MW treatments than for the co ntrol.