不同涂膜处理对云南新鲜天麻保鲜效果的影响

Effects of Different Coating Treatments on Preservation of Fresh Gastrodia elata in Yunnan Province

【目的】研究不同涂膜处理对云南新鲜天麻保鲜效果的影响。【方法】以云南省彝良县小草坝天麻为试材,以处理1(不涂膜)为对照,研究处理2(2%壳聚糖)、处理3(2%壳聚糖+20μl薄荷精油)对天麻贮藏过程中失重率、色差值L^*、a^*、b^*、c^*值、蛋白质含量、多酚氧化酶(PPO)、过氧化物酶(POD)、超氧化物歧化酶(SOD)活性变化的影响。【结果】各处理经过80 d的贮藏后,天麻失重率随着贮藏时间的延长而不断增加,最高达10%,L^*,c^*值不断下降,a^*,b^*值不断增加,蛋白质含量略微下降,PPO活性增加,最高至25 U/g,POD、SOD活性均先增加后降低。处理2天麻的失重率、POD、SOD活性比处理3低,处理3天麻的L^*,c^*值比处理2高,a^*,b^*值及PPO活性比处理2低。【结论】涂膜处理有利于天麻保存期的延长,不添加薄荷精油有利于保持天麻的水分和抗氧化性酶(POD/SOD)活性,而添加薄荷精油有利于减轻天麻色泽的变化。

【Objective】The purpose was to study the fresh-keeping effect of different coating treatments on Yunnan Gastrodia elata.【Method】Taking treatment 1(uncoated) as a control,the effects of treatment 2(2 % chitosan),treatment 3(2 % chitosan +20 μl mint essential oil) on weight loss rate,color difference L^*,a^*,b^*,c^* value,protein content,polyphenol oxidase(PPO),peroxidase(POD),superoxide dismutase(SOD) activity in gastrodia elata storage were studied,with Gastrodia elata(Yiliang,Yunnan)as material.【Result】After 80 days storage of all treatments,the maximum weight loss rate was 10 %,and L^*,c^* value decreased continuously,and a^*,b^* value increased,and the change range of protein content was small,and PPO activity increased continuously,the highest to 25 U/g,POD and SOD activity increased and then decreased.The weight loss rate,POD and SOD activity of Gastrodia elata of the treatment 2 were lower than the treatment 3.The L^* and c^* values of the treatment 3 were higher than the treatment 2,but its the a^* and b^* values,PPO activity were lower than that of the treatment 2.【Conclusion】The results indicated that coating treatment was beneficial to prolong the shelf life of Gastrodia elata.Without peppermint essential oil was beneficial to maintain the weight of Gastrodia elata and the activity of antioxidant enzymes(POD,SOD),but adding peppermint essential oil to reduce the color change of Gastrodia elata.