压榨对酿酒葡萄皮渣酚类物质提取及抗氧化活性的影响

酿酒葡萄皮渣（皮和籽）生物活性物质含量丰富，具有很高的再加工利用价值。对鲜葡萄皮渣进行压榨处理后再干燥，研究压榨对皮渣的酚类物质提取及抗氧化活性的影响。结果表明：压榨处理可以快速降低葡萄皮渣水分含量，缩短干燥时间、提高可溶性膳食纤维提取率。压榨葡萄皮总酚、原花青素的提取量均有所增加，其含量分别为19.56 mg/g和22.64 mg/g。压榨葡萄皮的抗氧化能力高于未压榨葡萄皮，其DPPH、ABTS及羟自由基清除率分别为62.90%、70.18%和41.09%，铁氰化钾还原能力及金属离子螯合能力分别为0.23%和21.33%。压榨籽和皮籽混合物的酚类物质和抗氧化活性则明显降低。抗氧化活性与总酚、原花青素存在显著的相关关系（P＜0.01）。

Effect of squeezing on phenolic compounds extraction and antioxidant activity of wine grape pomace

As grape pomace (including peels and seeds) is rich in bioactive substances, it has great value of reproducing and utilization. In this study, fresh wine grape pomace was squeezed and then dried, to study the effect of squeezing on the phenolic compounds extraction and antioxidant activity of pomace. The results showed that squeezing could quickly reduce the moisture content, shorten the drying time and enhance the extraction yield of soluble dietary fiber. The extract content of total polyphenols, proanthocyanidin in squeezed grape skin all increased, being 19.56 mg/g and 22.64 mg/g, respectively. The antioxidant activity of squeezed peels was higher than that of peels without squeezing. The DPPH, ABTS and HRSA scavenging capacity of squeezed peels were 62.90%, 70.18% and 41.09%, respectively. The potassium ferricyanide reducing power and metal-chelating activities of squeezed peels were 0.23% and 21.33%. However, as for the squeezed seeds and the pomace (mixture of seeds and peels), the phenolic compounds and antioxidant activity reduced significantly. There was obvious correlation of antioxidant activity with total polyphenols and proanthocyanidin（P＜0.01）.