Effect of Heat Shock Treatment on Browning and Related Enzyme Activities in Cold-Stored Broadbean Seeds

The effects of short term 45℃ heat-shock treatments for 30, 60 and 120 s on browning and activities of enzymes related to browning in broadbean( Vica faba L.)seeds during storage at 1℃ were investigated in this experiment. The results indicated that 45℃ treatment for 60 s significantly inhibited the respiratory rate(Fig.1A), PPO and PAL activities(Fig.3A, 4A), retarded the increase in MDA(Fig.1B), total phenolic content and browning degree(Fig.4B, 5B), inhibited the decreases in chlorophyll and Vc contents(Fig.2A, 5A), thereby delaying the senescence process and keeping better quality. Treatment with 45℃ water for 120 s, however, promoted the increase in MDA content(Fig.1B), browning degree(Fig.5B), and the decrease in Vc content(Fig.5A).