Effect of cell wall enzyme activity on the degredation of pectin during postharvest softening of plum fruit

To explore the postharvest softening and effect of cell wall enzyme activity (PE, exo-PG, endo-PG and EG) on the degradation of protopectin to souble pectin (WSP、ASP、HSP、SSP) , the experiment was carried out by Banbianhong plum using texture analyzer during storage at ordinary temperature. The results showed that, the changing of PE activity was little, exo-PG activity kept reducing, meanwhile endo-PG activity kept rising during the storage of pulm fruit and EG activity after storing 8d kept rising at ordinary temperature. The changing of pulp hardness and adhesiveness had a close relationship with the content of protopectin and SSP.The content of ASP affected the decrease of adhesiveness significantly (p <0.01) , while HSP affected pulp hardness significantly (p <0.05) . The changing of pulp hardness (p <0.01) and adhesiveness (p <0.05) had significant correlation with exo- PG activity. The changing of endo- PG activity presented a significantly correlation with the decline of pulp hardness (p<0.05) . The activity of PE presented a significantly correlation with the content of protopectin, ASP, HSP and WSP (p<0.05) , exo-PG presented a significantly correlation with the content of protopectin and HSP (p <0.01) , SSP and WSP (p <0.05) . Endo-PG had a great influence on protopectin and HSP (p<0.05) . EG had little effect on the degradation of pectin.