Resistance of heat‐shocked cells ofListeria monocytogenesto mano‐sonication and mano‐thermo‐sonication

Publisher Website
Google Scholar
Abstract
Heat shocks did not increase the resistance of Listeria monocytogenes to an ultrasonication treatment under pressure (Mano-Sonication; MS). While heat-shocked cells (180 min, 45 °C) became sixfold more heat resistant than native cells (D62 = 1·8 min vs D62 = 0·24 min), the resistance of native and heat-shocked cells to MS (200 kPa, 117 μm) was the same (DMS = 1·6 min). The inactivation rate of non-heat-shocked cells of L. monocytogenes by a combined heat/ultrasonication treatment under pressure (Mano-Thermo-Sonication; MTS) was an additive effect. On the contrary, on heat-shocked cells, the inactivation rate of MTS was greater than that of heat added to the inactivation rate of MS (synergistic effect) in the range 62–68 °C.