Survival of Listeria innocua in Minas Traditional Serro cheese during ripening

Cheese produced with raw milk can be a risk to consumer health. It is known that lactic acid bacteria present in raw milk and in natural starters can produce antimicrobial compounds against some food-borne bacteria. This work aimed to evaluate the survival of Listeria innocua in Minas Traditional Serro cheese during cheese ripening. The cheeses were inoculated with 10(1),10(2) or 10(3) CFU mL(-1) of the bacterium and were analyzed for 60 days of ripening at 30 degrees C. It was observed that the time and the dose of bacteria inoculated affected (p < 0.05) the survival of L innocua. Even when the lowest dose was inoculated, at the end of the 60 days, approximately 10(2) CFU mL(-1) of L. innocua was detected in the cheese. The lactic acid bacteria present in the milk and in the natural starter were not sufficient to guarantee the absence of L. innocua in Minas Traditional Serro cheese even after 60 days of storage, as is required by Brazilian legislation. (c) 2009 Elsevier Ltd. All rights reserved.