The Effect of Thermosonication Treatment on the Inactivation of Clostridium perfringens Spores

Clostridium perfringens spores, which are extremely resistant and difficult to kill, can easily cause food spoilage and foodborne diseases. In this study, the effect of simultaneous ultrasound and heat (thermosonication, TS) treatment for C. perfringens spore inactivation was investigated. The TS treatment at 26.67 W/mL and 80 °C or 90 °C for 30 min resulted in 5.77 and 5.89 log inactivation of C. perfringens spores, respectively. A strong synergistic effect of TS treatment on spore inactivation was observed. The mechanism of TS treatment on spore inactivation was further investigated by comparing the structural changes and release of substances in the spore core using microscopic and spectroscopic assays. The results revealed that TS treatment directly inactivated C. perfringens spores by destroying spore coat, cortex, and inner membrane, along with the release of calcium dipicolinic acid (Ca²⁺-DPA), protein, nucleic acid, and other substances in the spore core. This study could provide a method to control C. perfringens spores in food industry.