PEDIOCOCCUS-ACIDILACTICI PO2 BACTERIOCIN PRODUCTION IN WHEY PERMEATE AND INHIBITION OF LISTERIA-MONOCYTOGENES IN FOODS

Growth of Pediococcus acidilactici PO2 and production of associated bacteriocin (pediocin PO2) were demonstrated in whey permeate (WP) supplemented with 0.5-4% yeast extract (YE). Initial pH 6.5 (without PH regulation during fermentation) was optimal for production of pediocin PO2 in WP containing 2% YE. A pediocin-rich dairy ingredient (PRDI) powder was made of the fermented WP and applied in heat-treated whole milk and pasteurized liquid whole egg. PRDI inhibited Listeria monocytogenes in milk. L. monocytogenes was inhibited by untreated liquid whole egg and PRDI appeared to contain a factor that offsets the inherent antilisterial action of the egg product.