无核白绿葡萄干清洗前后酚类物质变化及其与酶促褐变的关系

Changes of Phenolic Substances in Seedless White and Green Raisins before and after Washing and Their Relationship with Enzymatic Browning

【目的】分析无核白绿葡萄干清洗前后酚类物质含量变化及其与酶促褐变的关系,为研究葡萄干清洗褐变机理提供理论依据。【方法】检测无核白绿葡萄干清洗前后酚类物质的含量变化,分析酚类物质与葡萄干多酚氧化酶反应的活性变化,判断参与酶促反应的底物,采用相关性方法,分析影响葡萄干清洗褐变的主要酚类物质。【结果】无核白绿葡萄干清洗前后有质量变化的酚类物质有槲皮素、儿茶素、咖啡酸、山奈酚、P-香豆酸、绿原酸、阿魏酸、原儿茶酸、香草酸、龙胆酸、芥子酸、丁香酸、没食子酸。其中槲皮素、绿原酸、咖啡酸、P-香豆酸、山奈酚、儿茶素为葡萄干清洗前后参与酶促褐变的主要酚类物质。【结论】无核白绿葡萄干清洗前后,葡萄干褐变度与槲皮素,咖啡酸,山奈酚,儿茶素含量呈显著性相关。

【Objective】By analyzing the changes of phenolic compounds before and after cleaning green raisins and their relationship with enzymatic browning,this project aims to explore the mechanism of enzymatic browning in cleaned green raisins.【Method】Through detecting the content changes of monomer phenols before and after cleaning green raisins,the activity changes of these phenols and polyphenol oxidase reaction of raisins were analyzed,and the substrates involved in enzymatic reaction were determined.At the same time,the main phenols affecting the browning of raisins during cleaning were obtained by correlation analysis method.【Result】Phenolic substances with quality changes before and after cleaning of green raisins included quercetin,catechin,caffeic acid,kaempferol,P-coumaric acid,chlorogenic acid,ferulic acid,protocatechuic acid,vanillic acid,gentisic acid,sinapic acid,syringic acid and gallic acid.Among them,quercetin,chlorogenic acid,caffeic acid,P-coumaric acid,kaempferol and catechin were the main phenolic substances involved in enzymatic browning of raisins before and after cleaning.【Conclusion】Before and after cleaning green raisins,browning degree of raisins is significantly correlated with quercetin,caffeic acid,kaempferol and catechin contents.The research results provide theoretical basis for exploring browning mechanism of raisins cleaning.