Inhibiting Effect Of Glutathione Treatment On Alcohol Softening Of Winter Jujube

Winter jujube(Zizyphus jujuba cv.Dongzao)is one of the characteristic agricultural products in Xinjiang.Its fruit is not only fresh and delicious,but also has high medicinal and nutritional value.In the process of storage,it is easy to produce a large amount of ethanol because of anaerobic respiration,accompanied by the phenomenon of softening and browning of jujube fruit which is called alcohol softening.The phenomenon of alcohol softening during storage greatly affected the fresh sales of jujube fruit.Therefore,it is of great significance to reduce the occurrence of alcohol softening and improve the storage quality of winter jujube.Taking semi red winter jujube as experimental material,fruits were soaked with 0.5 g/L,1.0 g/L and 2.0 g/L glutathione,and stored at 20±2 ℃ and 0±1 ℃.And then,study the effects of glutathione treatment on postharvest storage quality,cell wall metabolism and ethanol metabolism of winter jujube fruits in different conditions,and discuss the inhibitory effect of glutathione treatment on alcohol softening of winter jujube fruits.The main results are as follows:(1)The results showed that glutathione treatment had a certain inhibitory effect on alcohol softening of jujube fruit under different storage conditions,but compared with 0.5 g/L and 2.0 g/L,1.0 g/L glutathione treatment had the best effect on inhibiting alcohol softening of winter jujube fruit and reducing the decay rate.Besides,1.0 g/L glutathione treatment could effectively inhibit the increase of respiration intensity,cell membrane permeability and malondialdehyde content,slow the decrease of soluble solid content,titratable acid content and ascorbic acid content,and better maintain the firmness and color of winter jujube fruit.The results showed that 1.0 g/L glutathione treatment could effectively inhibit the softening and decay of winter jujube fruit,and better maintain the postharvest quality.(2)Under different storage conditions,1.0 g/L glutathione treatment could effectively inhibit the increase of activities of cell wall degrading enzymes,including PME,PG and CEL.The degradation of NSP and cellulose and the increase of WSP and CSP were delayed.The result indicated that inhibition of glutathione treatment on alcohol softening is closely related to the regulation of cell wall metabolism.(3)1.0 g/L glutathione treatment decreased the activities of ADH and PDC in winter jujube fruit,delayed the increase of ethanol and pyruvic acid content,which indicated that glutathione could reduce the alcohol softening of winter jujube fruit by regulating the activities of related enzymes of ethanol metabolism in winter jujube fruit.