Low-frequency ultrasonic treatment: A potential strategy to improve the flavor of fresh watermelon juice

A molecular sensory science approach was used to explore the effects of ultrasonic treatment on aroma compounds of watermelon juice. Watermelon juice was submitted to ultrasonic power at 325 W for 20 min. Ultrasonic treatment reduced odor related to cucumber and green descriptors, whilst significantly improved odors related to sweet, floral, and fruity descriptors, thus contributing to the overall flavor of watermelon juice. Compared with untreated watermelon juice, the amount and concentration of volatile compounds in ultrasonicated watermelon juice increased by 82.50% and 111.84%, respectively. Notably, 22 alkene compounds were newly formed in ultrasonicated watermelon juice, which contributed to sweet and fruity aroma of watermelon juice. The findings of the present study suggest that ultrasonic treatment may be a potential method to improve the overall flavor of watermelon juice.