Effect of Different Ratio of O_2-CO_2 on Enzymatic Browning Factors of Housui Pear Fruit During Postharvest Storage

Taking Housui pear fruit as test material,the effect of different ratio of O2∶CO2treatments on the browning of Housui pear fruit during storage(0±0.5)℃ was investigated by observing changes in respioratory intensity,ethylene production,elative electrical conductivity,MDA content,browning index,and the activities of polyphenol oxidase(PPO)and peroxidase(POD).The results showed that Housui pear was respiration climacteric fruit,appropriate ratio of O2∶CO2could reduce the growth of browning index.The times of peak occurrence of the activities of PPO and POD were postponed,the decomposition of phenolic compounds was inhibited,the formation of MDA was decreased,occurrence of browning of fruit was delayed,5% O2+1% CO2 had the best effect on inhibition of fruit browning.Phenolics content and PPO activity was highest in the peels,the second was the core,and at last the pulp,however,the activity of POD was skinfleshcore,but the skin and flesh browning were not happened during the storage.