柠檬精油复合涂膜对椪柑采后品质的影响

Effects of Compound Coating of Lemon Essential Oil Composite Coating on Postharvest Storage Quality of Ponkan

为提高柑橘的保鲜效果,本试验以椪柑为材料,研究柠檬精油及其与壳聚糖、氯化钙和纳他霉素复配对果实采后贮藏品质的影响。结果表明,柠檬精油及其与壳聚糖、氯化钙和纳他霉素复配可以降低果实腐烂率和失重率,抑制果实呼吸速率,延缓果实可滴定酸(TA)和维生素C(Vc)的降解,更好地维持果实营养价值和感官品质;柠檬精油及其复合物可提高果实超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活性,抑制果皮相对电导率的上升和果肉丙二醛(MDA)含量的积累。其中,1%柠檬精油+1%壳聚糖+1%氯化钙+300 mg·L^-1纳他霉素复配对椪柑保鲜效果最好,其果实Vc和TA含量最高,腐烂率、失重率、果皮相对电导率和果肉MDA含量最低,且在维持抗氧化酶(CAT、SOD和POD)活性方面的效果最优。本研究结果为柠檬精油及其复配物作为防腐剂保鲜果蔬提供了理论支撑。

To improve the fresh-keeping effect of citrus,the effects of lemon essential oil and its mixture with chitosan,calcium chloride and natamycin on postharvest storage quality of Ponkan mandarin were investigated in this study.The results showed that all the treatments could reduce the rate of fruit decay and weight loss,inhibited respiration rate,and delayed the decompostion of titratable acids and Vc,which helped to maintain nutritional value and preserve sensory quality of ponkan.In addition,lemon essential oil and its mixture also significantly enhanced the activities of SOD,CAT and POD,and inhibited the increase of relative electric conductivity and accumulation of MDA content during storage.Specially,the ponkan treated by the mixture with 1%lemon essential oil,1%chitosan,1%calcium chloride and 300 mg·L^-1 natamycin had the highest contents of titratable acids and Vc,the lowest rate of fruit decay and weight loss,MDA content and relative electric conductivity,and better activities maintenance of SOD,CAT and POD,all of which suggested that this mixture had the best fresh-keeping effect for the storage of ponkan.These results will provide theoretical evidence for using lemon essential oil mixture as preservative for the storage of fruits and vegetables.