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The influence of ultrasonic technology on the sterilization effect and quality of Cucurbita pepo juice were studied in this paper. The sterilization rate under conditions of control 100W, 200W, 300W ultrasonic, color difference, total chlorophyll content, pH changes on juice Cucurbita pepo were determined. The results showed that the total color difference, browning index, whiteness index and total chlorophyll content of the juice had significant changes, while the pH had no significant changes. Ultrasonic has a certain influence on the sterilization effect of Cucurbita pepo, and ultrasonic treatment is helpful to maintain the quality of pumpkin juice in a certain range. In the future, it is hoped that ultrasonic technology will combine with other technologies to achieve commercial sterility while minimizing the loss of quality in Cucurbita pepo.

The objective of this study was to investigate the effects of ultrasonic treatment on the aroma profile of pumpkin juice. Samples were treated according to the experimental design, with a numerically controlled ultrasonic instrument at an ultrasound frequency of 45 kHz under various conditions (treatment times of 10, 20, and 30 min, sample temperature of 25(± 2)∘C, and powers of 180, 240, and 300 W). The aromatic profiles of pumpkin juice showed that a total of 52 volatile components were detected in the 10 groups of pumpkin juices, including 16 alcohols, 11 alkane olefins, 6 aldehydes, 4 ketones, 4 esters, and 11 others. Alcohol compounds had the highest content among all volatile compounds; the most abundant were 1-Octen-3-ol, (E, Z)-3, 6-Nonadien-1-ol, 1-hexanol, and (Z) -3-Nonen-1-ol. Compared to the untreated samples of juices, ultrasonic treatment leads to the formation of new compounds or the disappearance of compounds found in the untreated samples. The findings presented in this study provide a deeper understanding of the application of ultrasound to enhance the volatile components of pumpkin juice.

In this study, single factor experiment and orthogonal experiment were used to study the extraction effect of carotenoids from navel orange in southern Jiangxi Province assisted by ultrasonic technology. The experimental results showed that when hexane: ethanol=1:1 as the extraction agent, liquid to solid ratio of 1:30, extraction time of 8 min, ultrasonic power of 250 W, extraction temperature of 25°C, extraction times of 4 times, the best extraction effect of carotenoids from Gannan navel orange was obtained.