Abstract: Enzymatic browning is a kind of physiological disease harmful to the pear postharvest qualities during storage. The enzymatic browning and physio-biochemical changes of Cuiguan pear were studied during : A, the room temperature storage; B, the cold storage (0℃) and C, the cold storage (0℃) in polyethylene film bags of 0.04mm thickness storage. The results indicated. (1) After 16 days’ storage, the A、B and C treatment could keep the good fruit rate of Cuiguan pear as 25.12%, 87.27% and 98.64%, respectively. The cold storage (0℃) could increase the activity of superoxide dismutase (SOD), inhibit the producing rate of active oxygen and MDA and delay the senescence and softening. (2) During the storage the phenol compounds were synthesized in Cuiguan pear at first ,then decomposed. The activity of polyphenol oxidase (PPO) took place first, then degraded. Following the decrease of phenol compounds, the browning reaction took place. The oxidization of phenol compounds pro- moted by PPO was considered the cause.

Key words: Cuiguan pear, storage, enzymatic browning, physio-biochemical change