摘要
葡萄的褐变与其有机酸的代谢密切相关,褐变的程度与有机酸含量下降的梯度成正比。有机酸含量的降低使pH向碱性方向移动,从而诱发多酸氧化酶的活性,引起褐变。所以一定含量的有机酸是保持果实品质、防止酶促褐变的重要因素。贮藏期间,无核白葡萄有机酸含量急剧减少,pH环境变化剧烈,果实褐变程度最重;喀什哈尔葡萄有机酸贮备的绝对值虽然小于无核白,但下降平缓,变化幅度小,所以褐变程度小于无核白;木纳格葡萄有机酸的损失最少,pH环境变化细微,无褐变发生。所以多酚氧化酶引起果实褐变与有机酸损失率有密切关系。
The relationship between the browning and metabolism of organic acid is close in grapes, and comes the direct ratio. The reduction in the content of organic acid makes pH move toward the basicity,and the result makes PPO activity to be brought out,and the browning occured with the increasing of PPO activity. So, just the right amount of organic acid is important to keep the quality and to prevent the browning impelled by PPO in grapes.Organic acid content in Wuhebai grape reduces rapidly during storage,so the change of pH is obvious in the grape,and the browning degree is the most serious among three varieties. The absolute value of organic (?)cid in Kashihaer grape is less than that in Wuhebai grape,but its reduction is gently,that is to say,the changing range is narrow,so,its browning degree is lighter than that of Wuhebai grape. The loss of organic acid in Munage grape is the least,so is the chang of pH,and there is not browning in the grape. So,there is a close relationship between the browning caused by PPO and the loss rate of organic acid in grapes.
出处
《干旱区研究》
CSCD
北大核心
1992年第4期68-71,共4页
Arid Zone Research
关键词
葡萄
贮藏
有机酸
代谢
褐变
grapes
storage
organic acid
browning
