Evaluation of processing characteristics of beverage by different purple-fleshed sweetpotato （ Ipomoea batatas L.） varieties

In order to understand the effects of raw material varieties on stability of purple-fleshed sweet potato （Ipomoea batatas L.） beverage，nine varisties of purple-fleshed sweetpotatoe were collected from Guangdong Province，and the stability of beverage was compared during the storage at room temperature. The results showed that there were no significant changes in the value of pH，contens of total soluble solid and phenolics. After 30 days， the amount of precipitate of Guangshu No. 11-173，12-87，and 13-79 increased by 58.6%，105.8%，and 68.4%， respectively，while the relative turbidity declined sharply at 15 d，the results indicated that the suspension stability of beverage made from these purple-fleshed sweetpotatoes was poor，and the three cultivars were suitable for makingclear beverage after clarified. Small amout of precipitate and no significant changes in relative turbidity were observed in Guangzishu No. 2，8，9，11，and Guangshu No. 13-203，the results suggested that these cultivars were suitable for cloudy beverage processing. The least change of colour was observed in Guangzishu No. 9，and the total chromatic aberration ΔE* increased 5.70. The highest content of total phenolics was found in Guangzishu No. 9，which reached 150.5 mg/100mL，followed by Guangzishu No. 11 and Guangshu No. 11-173；while the highest content of total anthocyanins was observed in Guangzishu No. 11，which reached 20.5 mg/100mL，followed by Guangshu No. 11-173 and Guangzishu No. 9. The results suggested that the cultivars were suitable for functional beverage processing.