Influence of temperature and sakacin A concentration on survival ofListeria innocua cultures

Abstract

The antimicrobial activity of sakacin A, a bacteriocin produced byLactobacillus sakei, was investigated at 30, 10 and 4°C againstListeria innocua in stationary and lag phases of growth. When sakacin was added toListeria innocua cells in stationary phase, two death kinetics were observed. Populations ofListeria innocua were reduced up to threelog cycles when sakacin A was increased from 0 (control) to 1600 AU ml−1. When sakacin A was added toListeria innocua cells in lag phase, lag time, inhibition time and rate were proportionally extended, and maximum population decreased when employing higher bacteriocin levels. Sakacin A was found to influenceListeria innocua growth, a microorganism able to grow at 4 °C. At refrigerated temperatures, the addition of sakacin A was found to inhibitListeria innocua cell growth. Sakacin A may be considered a promising molecule to be used as antimicrobial agent to preserve the shelf life of refrigerated foods.