Sterilization effects of thermo-sonication treatment on Salmonella

The new sterilization technologies of high efficiency and low effect on nutritional components have been widely concerned.The reconstituted milk, was inoculated with Salmonella, and sterilization effects of thermos-sonication treatment were studied.The physicochemical parameters of pre-and post-treatment were also analyzed in this study.The results showed that the significance order of factors affecting the killing logarithm value was: ultrasonic temperature, ultrasonic time, and ultrasonic power.Taking 5.0 killing logarithm value ( the percentage of killing rate was 99.999% for Salmonella) as reference, the optimal sterilization conditions were: ultrasonic time of 8.8 min, ultrasonic power of 307 W, and ultrasonic temperature of 50 ℃.Under these conditions, the physicochemical parameters did not change obviously, and the diameter of fat globules was reduced remarkably ( p < 0.05) , only 17.86% of pre-treatment sample.Therefore, it indicates that the thermo-sonication technique has huge potential for application as a sterilization method in liquid milk industry.