Antilisterial effect of two bioprotective cultures in a model system of <scp>I</scp>berian chorizo fermentation

Abstract

Summary This study reports the different effects of two bioprotective cultures on the growth of different L isteria monocytogenes strains by a rapid assay simulating the first stage of I berian chorizo fermentation. Ground pork with or without protective cultures was inoculated with L . monocytogenes and incubated under two different conditions simulating the traditional, slow fermentation temperature (7 °C, 1 day) and a high, fast fermentation temperature (20 °C, 1 day), followed in both cases by storage at 7 °C for 13 days. Both bioprotective cultures reduced the growth of L . monocytogenes by at least 2 log CFU g −1 at the end of both incubation periods compared with a noninoculated culture control lot. The best results were obtained with the strain L actobacillus sakei CTC 494, which exerted a bactericidal effect on L . monocytogenes under both conditions assayed, achieving a 5.4‐log reduction after 14 days compared with the control when the initial temperature was 20 °C.