关键词: 北碚447锦橙, 果皮结构, 果皮褐变, 生理特征

Abstract:

To reveal the occurrence mechanism of peel pitting of＂Beibei 447 Jincheng＂orange, physiological, biochemical and microstructural changes of ＂Beibei 447 Jincheng＂orange stored under normal temperature and ventilation condition were measured before and after pitting, and their relationships with pitting were investigated. After the formation of pitting, ＂Beibei 447 Jincheng＂ orange peel became crimpled and shriveled. Besides, disruption and atrophy of oil vacuole and deformation of cells around oil vacuole were both observed, and safranine dyed samples exhibited a deep color. A significant correlation was observed among peroxidase (POD), superoxide (SOD), polyphenoloxidase (PPO) activities and relative electrical conductivity (REC) or between these parameters and peel pitting rate. The occurrence of peel pitting was due to the interactions among these parameters. Moreover, there was no linear relationship between PPO activity and total phenol content. Thus, POD, SOD and PPO activities and REC can be considered crucial physiological features indicating peel pitting occurrence.

Key words: ＂Beibei 447 Jincheng＂ orange, microstructure of peel, peel pitting, physiological features