不同梨果实褐变特异性分析

以黄金梨、大香水、新梨七号为试材,研究了贮藏后梨褐变不同部位酚类物质含量和种类、多酚氧化酶(PPO)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)的活性及可溶性蛋白的关系。结果表明,梨果实中的酚类物质以绿原酸为主,果实褐变与酚类物质含量和多酚氧化酶活性,特别是二者在果实中不同部位的分布特性有关。黄金梨果心与其他部位比较具有较高的酚类物质含量和PPO活性。由果皮至果心CAT活性依次降低,而果皮中POD活性极大地高于其他部位。SOD的活性与褐变的直接关系不明显。

Analysis of Browning Characteristic in Pear Fruits

The enzymatic browning and physio-biochemical changes of Whangkeumbae?Daxiangshui and Xinli No.7 were studied during the late storage. The activities of enzymes including Polyphenol Oxidase (PPO), Superoxide Dismutase(SOD), Catalase(CAT), Peroxidase (POD) and the contents of soluble protein, phenolics contents and varieties in the pericarp, sarcocarp and core of the pear fruits were measured. The results showed that the contents of chlorogenic acid was the main phenolics in pear fruit, the fruit browning was related to the contents of phenolics and PPO activity, especially the distribution in the different parts of the pear fruit. The highest of content of phenol and PPO activity among the tested parts were in the core of fruit in Whangkeumbae. CAT activity gradually decreased from the pericarp to the core of fruit and POD activity was much higher in the pericarp than that in other parts. No marked relationship between SOD activity and browning was observed.