曲酸对鲜切马铃薯与莲藕的褐变及其相关酶活性的影响

以马铃薯(Solanum tuberosum)、莲藕(Nelumbo nucifera Gaertn)为试材,研究了0.1%、0.3%和0.5%曲酸处理鲜切马铃薯片及莲藕片在模拟货架期(4℃)的色泽及相关酶活性变化。结果表明,曲酸能不同程度地抑制马铃薯与莲藕的多酚氧化酶(PPO)、过氧化物酶(POD)和苯丙氨酸解氨酶(PAL)的活性。其中,0.3%和0.5%曲酸处理在保持鲜切马铃薯片及莲藕片色泽,抑制PPO,POD,PAL活性的效果好于未经处理的对照及1%柠檬酸的参比处理。未经处理的马铃薯片、莲藕片外观品质保持为5~6d或4~6d,0.3%和0.5%曲酸处理后的马铃薯片与莲藕片的货架期分别达10d或12d,1%柠檬酸的参比处理分别是8~10d或6~8d。

Role of kojic acid in changes of browning and activities of its related enzymes from sliced Potato and Lotus

The changes of browning degree and activities of polyphenoloxidase （PPO）, peroxidase （POD） and phenylalanine ammonialyase （PAL） in sliced potato （Solanum tuberosum） and lotus（Nelumbo nucifera Gaertn）treated by kojic acid at 0.1% ,0. 3% or 0.5% were investigated during shelf life at 4 ℃. The results showed that the treatments of kojic acid inhibited the browning and activities of PPO, POD and PAL. The treatments with 0.3% and 0.5% kojie acid gave better effects on maintaining color of sliced potato or lotus and inhibited activities of PPO, POD and PAL than those in the untreated or the treatment with 1% citric acid. The shelf life with the acceptable appearances of sliced potato or lotus at 4 ℃ were 5-6 d or 4-6 d in the untreated,10 d or12 d in 0.3% or 0.5% kojie acid% 8-10 d or 6-8 d in 1% citric acid, respectively.