Destruction of Salmonella enteritidis in liquid egg white as the function of treatment temperature and heating rate

In our study we investigated the effect of heat treatment temperature and heating rate on heat resistance of Salmonella enteritidis. The samples were heated from 4 °C to 48,96-56,04 °C by a heating rate 0,76-9,24 °C·min-1 and the changes of the colony counts were determined at given time by plating to XLD agar with overlay. We used Central Composite Rotatable Design (CCRD) in our experiment and Response Surface Method (RSM) was used to evaluate the data. Our results pointed out that beside the temperature of heat treatment the heating rate have also an effect on the heat destruction of Salmonella enteritidis. In case of heating rate 9,24 °C·min-1 the D52,5-value was 2.32 min, however at heating rate 0,76 °C·min-1 the D52,5-value was 19.23 min. In our measurements the samples were heated with linear heating rate in laboratory scale. so further studies are necessary to describe the heat resistance changes of Salmonella enteritidis under parameters which model the industrial heating circumstances