油橄榄叶多酚的酶法提取及稳定性研究

Enzymatic Extraction and Stability of Polyphenols from Olive Leaves

以橄榄叶为原料,运用酶法提取叶片中多酚类物质,并对其加工稳定性进行探讨。在优化复合酶配比的基础上,采用单因素和均匀试验设计方法,考察酶解时间、酶解温度、pH值、酶用量和料液比5个因素对橄榄叶粗多酚得率的影响。并在此基础上,研究甜味剂、防腐剂、氧化剂和还原剂对油橄榄叶粗多酚加工稳定性的影响。结果表明:复合酶的最佳配比为纤维素酶∶果胶酶∶中性蛋白酶为1∶1∶2;橄榄叶粗多酚的最佳提取方案是酶解时间40 min,酶解温度72℃,pH值4.2,酶用量7.1%,料液比1∶52(g/mL);粗多酚在葡萄糖、蔗糖、阿斯巴甜和木糖醇溶液中的稳定性依次降低;低浓度山梨酸钾中多酚稳定性较好,山梨酸钾对多酚稳定性整体优于苯甲酸钠;高浓度氧化剂和还原剂对多酚稳定性均有较大影响。

Take olive leaves as the raw materials,the polyphenols in olive leaves are extracted by enzymatic method,and the processing stability is discussed.On the basis of optimizing the ratio of complex enzyme,single factor and uniform experimental design method are used to investigate the effects of five factors such as enzymolysis time,enzymolysis temperature,pH value,dosage of enzyme and ratio of solid to liquid on the yield of crude polyphenols from olive leaves.On this basis,the effects of sweeteners,preservatives,oxidants and reductants on the processing stability of crude polyphenols from olive leaves are studied.The results show that the optimum ratio of complex enzyme is cellulase∶pectinase∶neutral protease of 1∶1∶2;the optimum extraction scheme of crude polyphenols from olive leaves is enzymolysis time of 40 min,enzymolysis temperature of 72℃,pH value of 4.2,enzyme dosage of 7.1%and solid-liquid ratio(g/mL)of 1∶52,the stability of crude polyphenols in glucose,sucrose,aspartame and xylitol solution decreases in turn,the stability of polyphenols in low-concentration potassium sorbate is better than that in sodium benzoate,and the stability of polyphenols in high-concentration oxidant and reductant is greatly affected.