鲜切黄藤笋褐变与3个酶活性变化的灰色关联分析

Grey Relational Analysis between the browning and related enzyme activities in fresh-cut Daemonorops margaritae shoots

黄藤笋是指黄藤嫩梢中的可食部分,是一种有待开发的森林保健蔬菜,褐变是导致鲜切黄藤笋品质劣变的主要原因。对可能导致黄藤笋褐变的3个酶活性进行动态测定并作灰色关联分析,结果表明,鲜切黄藤笋在10℃下贮藏28 d过程中,亮度L*值逐步下降,即褐变加重;过氧化物酶(POD)、多酚氧化酶(PPO)和苯丙氨酸解氨酶(PAL)活性先上升后下降,后期POD活性有所回升,PPO活性持续下降,PAL活性则维持低水平。POD、PPO和PAL活性与褐变度的灰度关联系数分别是0.8968、0.8074和0.5977,表明POD和PPO在鲜切黄藤笋酶促褐变过程中起主导作用。

The shoot of Daemonorops margaritae（Hance） Beccari,central eatable part in the tip of the rattan,was a potential resource of forest vegetable.Rapid browning is the main postharvest defect of fresh-cut D.margaritae shoots.In this study,fresh-cut D.margaritae shoots were stored for 28 days at 10℃ and the browning index（the L＊ hunter value or lightness） and activities of phenylalanine ammonia-lyase（PAL）,polyphenol oxidase（PPO） and peroxidase（POD） were measured in an interval of 7 days.The results showed that the L＊ hunter values decreased steadily during storage,showing obviously browning occurred during this period.POD,PPO and PAL enzymatic activities showed a general trend of increase in the first 7 days and of decrease thereafter.But POD activity recorded a slight rebound,PPO activity demonstrated a gradually decrease,while PAL activity kept the low level in the last period.Grey relational coefficient between the browning and enzymatic activities of POD,PPO and PAL were 0.8968,0.8074 and 0.5977 respectively,indicated that POD and PPO played a leading role in enzymatic browning of fresh-cut D.margaritae shoots.