短波紫外线处理对采后香菇褐变的影响

Effects of Shortwave Ultraviolet Treatment on the Browning of Postharvest Lentinula edodes

为了控制采后香菇在贮藏过程中的褐变并提高其贮藏品质,本试验采用不同剂量(2、4、6和8 kJ·m^(-2))短波紫外线(UV-C)对新鲜香菇进行预处理,研究不同剂量UV-C处理对香菇色泽、总酚含量、多酚氧化酶(PPO)活性、过氧化物酶(POD)活性、超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性、苯丙氨酸解氨酶(PAL)活性、可溶性蛋白含量、还原糖含量、游离氨基酸含量以及香菇表面微生物的影响。结果表明,UV-C处理延缓了香菇色泽的下降,保持了较高的总酚含量,并且有利于POD、SOD、CAT和PAL活性维持在较高水平,抑制了PPO活性,同时可以保持较高的还原糖和可溶性蛋白含量,在一定程度上延缓了蛋白质的降解,而且可以有效抑制微生物的生长,其中4 kJ·m^(-2) UV-C处理效果最佳。综上所述,UV-C处理可以有效地抑制香菇褐变,延长其贮藏期。本研究结果为香菇的贮藏保鲜提供了理论依据。

In order to control the browning of postharvest Lentinus edodes during its storage and improve the storage quality,different doses(2,4,6 and 8 kJ·m^(-2))of shortwave ultraviolet(UV-C)were applied to the fresh Lentinus edodes.The effects of different doses of UV-C on the color,total phenol content,polyphenol oxidase(PPO),peroxidase(POD),superoxide dismutase(SOD),catalase(CAT),phenylalanine ammonialyase(PAL),soluble protein,reducing sugar,free amino acids and surface microorganisms of Lentinus edodes were investigated in this study.The results showed that UV-C treatment could delay the color decline of Lentinus edodes,maintaining a high content of total phenols,which also helped to maintain the activities of PAL,SOD,CAT and POD at a higher level.The activity of PPO was inhibited and the degradation of protein was delayed to a certain extent.The content of reducing sugar and soluble protein was maintained at a higher level,which all effectively inhibited the growth of microorganisms.Among them,4 kJ·m^(-2) UV-C treatment was the best effective.In this study,UV-C treatment can effectively inhibit the browning of Lentinus edodes and prolong its storage period,which supports for the preservation of Lentinus edodes.