Abstract:
In order to investigate the relationship between microwave pretreatment of raw apple and browning of apple juice, the effects of different microwave power and time treatment on the browning of apple juice during apple juice processing were studied. The results indicated that microwave treatment could improved the color value, reduced the activity of polyphenol oxidase and the content of total amino-nitrogen, and slightly increased the acidity of apple juice. With the microwave power of 720-900 W and time of 75-125 s, the color value of apple juice was higher, after 45 days storage at room temperature, with the microwave power of 900 W and time of 100 s, the color value of apple juice was 67.8 (91.5% higher than the control). Microwave pretreatment of raw apple to prevent the browning of apple juice is a simple, safe, feasible and economical processing method.