Abstract: In order to accelerate the dissolution of intracellular anthocyanins into grape juice, Cabernet Cauvignon grapes were mechanically crushed and subjected to pectinase hydrolysis followed by microwave treatment. The conditions of pectinase hydrolysis and microwave treatment were optimized by Box-Behnken experimental design combined with response surface methodology for maximizing anthocyanin content in grape juice. Based on Box-Behnken experimental design, two regression models describing pectinase hydrolysis and microwave treatment were established. The optimal pectinase hydrolysis conditions were pectinase amount 1.1‰, hydrolysis temperature 40 ℃, and hydrolysis time 3.15 h, and the optimal microwave treatment conditions were grape amount 129.5 g, treatment time 19 s, and number of repeated treatments 3. Analysis of variance indicated that the two mathematical models were highly statistically significant (P＜0.0001), the lack of fit of each of which was not significant (P＞0.1), thereby being applicable to analyze and predict the dissolution of anthocyanins during grape juice processing. Grape juice with a higher anthocyanin content and a brilliant color can be obtained by the combined use of pectinase hydrolysis and microwave treatment.

Key words: Cabernet Cauvignon grape, anthocyanin, microwave, pectinase, response surface design