Ultrasound-synergized gas in ensuring the sterilization and physicochemical quality of fruit and vegetables: A review

Ultrasound has attracted abundant research interest due to its advantages of high efficiency and low-carbon. Many researchers have proven the effect of ultrasonic treatment in controlling pathogenic microorganisms in fruit and vegetables (FVs) to ensure the quality and safety of FVs. However, ultrasonic treatment alone has limited influence on microorganisms, and the hurdle technology which combines it with other sterilization techniques is an effective way to address its drawbacks. Some gases (O3, CO2, ClO2, etc.) have a broad-spectrum bactericidal effect, when combined with ultrasound, they can significantly improve the antimicrobial effect on FVs and reduce the production of toxic substances. This paper reviews the effects of sonoporation, sonochemistry and sonoluminescence caused by ultrasonic cavitation effects, focuses on the antimicrobial synergistic mechanism and applications of ultrasound with gas in ensuring the quality and safety of FVs. Furthermore, this review presents an outlook on the challenges required to overcome in the future, hoping to provide a reference for the future practical utilization of ultrasound with gas to promote the sterilization effect and preserve the physicochemical quality of FVs.