INHIBITION OF LISTERIA-MONOCYTOGENES BY CARNOBACTERIUM-PISCICOLA IN VACUUM-PACKAGED COOKED CHICKEN AT REFRIGERATION TEMPERATURES

Listeria monocytogenes inhibition by bacteriocinogenic Carnobacterium piscicola DX or nonbacteriocinogenic C. piscicola 2818 was examined in vacuum-packed minimally processed chicken cubes with gravy at 4, 8 an d 15C. C. piscicola DX and C. piscicola 2818 at 10(4) CFU/g were coino culated individually with a pool of three Listeria monocytogenes strai ns at 10(2) CFU/g. At 4 and 8C, C. piscicola DX inhibited growth oft. monocytogenes by 3 logs, significantly (p < 0.05) more than did C. pis cicola 2818. At 15C both C. piscicola strains inhibited L. monocytogen es by one log cycle. The pH of all inoculated systems decreased from a n initial pH of 6. 14 to final values ranging from 6.06 to 5.65 depend ing on the inocula used. Bacteriocin was detected in the systems coino culated with C. piscicola DX. These studies demonstrate that lower tem peratures and bacteriocin production enhanced L. monocytogenes inhibit ion by C. piscicola.