Verification of prediction of growth of Listeria monocytogenes micro-organism in chicken meat

Abstract

Raw chicken meat was comminuted and homogenised. There were measured water activity and pH (aw = 1 for temperature 25°C, pH = 5.8 for temperature 8°C). Input raw material was investigated for the presence of Listeria monocytogenes (negative) and the raw meat was inoculated by Listeria monocytogenes CCM 4699. Number of Listeria monocytogenes, total plate count and number of coliforms were determined in the range 0-7 days by bacteriological survey for the storage temperatures 4.9, 7 and 8.3°C. The increase of Listeria monocytogenes counts has been registered for temperature 4.9°C about log 1.5 CFU/g after 6 days, for temperatures 7 and 8.3°C about 2 log CFU/g (regarding to the starting counts). The prediction for listeria growth with the aid of Food MicroModel was also made. The best agreement between the experimentally analysed number of bacteria and prediction was received for the lowest incubation temperature 4.9°C.

Keywords

• micro-organism
• listeria monocytogenes
• chicken meat
• food micromodel verification