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In this study, the efficacy of ultrasonication for bacterial inactivation at two different temperatures (10 and 50C) in different model systems (saline, nutrient broth, and sterilized sugarcane juice) and natural sugarcane juice was studied. The survival of bacterial cells in response to various treatments was affected by the sonication medium. The heat and ultrasound resulted in significantly (p < 0.05) higher reduction in the viability of cells in sterile sugarcane juice and saline. The kinetic study showed a significant correlation (R2 = 0.86–0.99) between treatments and inactivation of bacteria. The time required for 5 log reduction was also lower for thermosonication as compared to sonication in all the model systems. This observation was confirmed in case of natural sugarcane juice, where higher log reduction was obtained at 50C as compared to 10C ultrasonication. Thus, by applying the additional heat along with ultrasound, faster inactivation could be achieved. Practical Applications Fresh sugarcane juice is considered as a refreshing drink around the globe; however, its availability is limited due to poor keeping quality, mainly attributed to the microbial spoilage. This article investigated the combined effect of ultrasound and heat treatment for the control of microbial growth in sugarcane juice. The application of low level of heat in combination with ultrasound resulted in higher loss in the viability of microbial cells as compared to ultrasound alone. This alternative method for preservation of sugarcane juice developed here can be utilized not only to enhance its shelf life but also to retain nutritional value.

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