砂梨果肉褐变与酚类物质及相关酶活性的相关分析

Correlation analysis of flesh browning between phenolic compound and relavent enzymatic activity in fruit of Pyrus pyrifolia

【目的】为了探明砂梨褐变的内在机制,为砂梨贮藏与加工过程中品种选择和褐变控制提供理论依据,【方法】以11个砂梨品种的成熟果实为试材,测定总酚与酚类物质组成及含量、GSH含量、PPO、SOD、CAT、PAL、POD酶活性等相关指标。【结果】结果表明,不同品种酶促褐变程度有很大差别,‘新兴’和‘早生黄金’褐变较重,而‘秋黄’和‘丰水’较轻。绿原酸、儿茶素、芦丁和没食子酸是梨果肉中含量较高的酚类物质。总酚含量与果实褐变度相关性最高,绿原酸次之,儿茶素最低。【结论】梨果肉褐变相关酶活性与酚类物质组分及含量对其酶促褐变的影响程度因品种不同而存在差异。梨果肉酶促褐变与总酚和绿原酸含量的相关度高于与酶类的相关度。

【Objective】The study was to reveal the internal mechanism of browning in Pyrus pyrifolia Nakai and to provide theoretical foundation for the cultivar selection and the browning control during processing and storage.【Method】With 11 pear cultivars（＇Whangkeumbae＇,＇Hosui＇,et al.） as the experimental materials,total phenol and phenolic compound contents,GSH content,PPO,SOD,CAT,PAL,and POD activities in fruit were analysed.【Result】The results showed that the enzymatic browning level exhibited remarkable difference among tested cultivars,and the browning of ＇Xinxing＇ pear and ＇Josengwhangkeum＇ was more severe while ＇Qiuhuang＇ and ＇Hosui＇ was less.Chlorogenic acid,violaquereitrin,（＋）-catechin,gallic and caffeic acids were higher concentrated polyphenols in fruit.Total polyphenoics had the highest correlation with browning,followed by chlorogenic acid.Comparatively,（＋）-catechin had the lowest correlation with browning.【Conclusion】The influence of the activity of enzymes related to fruit browning,phenolic composition and their contents on enzymatic browning varied in different varieties.The correlation between total phenol or chlorogenic acid and enzymatic browning of fruit was higher than that between enzymes and browning.