怀山药多酚氧化酶特性及其无硫护色研究  

Study on properties of polyphenol oxidase in dioscorea opposite and antibrowning without sulphite

作　　者：陈艳珍[1] 任广跃[1] 张仲欣[1] 

机构地区：[1]河南科技大学食品与生物工程学院,洛阳471003

出　　处：《中国食品添加剂》2009年第5期107-112,共6页China Food Additives

基　　金：河南省重点科技攻关计划项目(编号:092102110023);河南科技大学科学研究基金项目(编号:2008ZY040)

摘　　要：以新鲜怀山药为试验材料,邻苯二酚为底物,在408nm波长下,采用分光光度法测定怀山药多酚氧化酶的活力。研究了pH、温度、底物浓度和抑制剂等不同因素对怀山药多酚氧化酶活力的影响,结果表明,怀山药多酚氧化酶的最适pH=6.0,最适温度为30℃,热稳定性随着加热时间的增加而趋于降低,多酚氧化酶的活力随底物浓度的变大而增高,随酶液浓度的变大而成直线上升趋势;L-半胱氨酸、柠檬酸、维生素C及NaCl四种抑制剂都能达到不同程度的抑制效果。正交试验结果表明,怀山药的最佳无硫护色配比为:L-半胱氨酸、柠檬酸、维生素C及NaCl的质量分数分别为0.02%、1.4%、0.016%和2.5%,浸泡时间为3h。Polyphenol oxidase activities of fresh Dioscorea opposite were spectrophotometrically determined at 408 nm with pyrocatechol as substrate at different pH,temperatures,substrate concentrations and inhibitors and so on.The results showed that the optimum pH and temperature for PPO activity was 6.0 and 30℃respectively,thermal stability of polyphenol oxidase was declined as the heating time increasing.Besides,polyphenol oxidase activity could be enhanced with raising substrate concentration and grew sharply with enzyme concentration increasing.Polyphenol oxidase activity could be restrained by four inhibitors (L-cysteine,citric acid,VC and NaCl) in varying degrees.The results of the orthogonal experiment showed that the optimal antibrowning without sulphite composition of Dioscorea Opposite was L-cysteine 0.02%,citric acid 1.4%,VC 0.016%,NaCl 2.5% and steeping time 3h.

关 键 词：怀山药 多酚氧化酶 酶特性 护色 

分 类 号：TS201.2+5[轻工技术与工程—食品科学]