果肉的褐变机理

Physiological mechanism of flesh browning of nane

木奈果肉褐变是酚类物质、多酚氧化酶与氧结合起酶促反应的结果．但酚、酶在果肉细胞中是区域化分布的，果实含Ｃａ量降低使膜透性增加，为酚、酶和氧接触提供了条件，果实缺Ｃａ是木奈果肉褐变的主要原因，通过提高果实的含Ｃａ量可有效地防止果肉褐变．

In this test, flesh browning of nane was caused by the combination of phenolics, polyphenol oxidase and oxygen, but phenolic and polyphenol oxidase were compartmentalizedly distributed in flesh cell and the low calcium content of fruit could cause the increase in cell membrane permeability, which provided the available condition for the combination of phenolics, polyphenol oxidase and oxygen. Therefore the deficiency in the calcium content of fruit was the main reason for flesh browning of nane and increasing the calcium content of fruit could prevent the flesh of nane from browning.