壳聚糖与柠檬酸复配涂膜液对草莓保鲜效果的研究

Study on The Fresh-keeping Effects of Chitosan and Citric Acid Complex Films on Strawberry

将草莓分别进行壳聚糖1%-柠檬酸2%、壳聚糖1%-柠檬酸3%、壳聚糖1%-柠檬酸4%、空白对照4种方式涂膜处理,于4℃下贮藏5 d,对其采后生理指标(颜色、硬度、腐烂率、可溶性固形物、呼吸强度、过氧化物酶和多酚氧化酶活性等)进行测定。结果表明:壳聚糖涂膜能减缓草莓贮藏过程中的褐变程度,延缓草莓果肉的软化,降低草莓的腐烂率;壳聚糖处理的草莓样品组的呼吸强度分别由32.65,33.59,32.31 m L·(kg·h)-1升至69.98,62.42,64.63 m L·(kg·h)-1,而对照组的呼吸强度升至83.98m L·(kg·h)-1,其中壳聚糖1%-柠檬酸4%涂膜液的保鲜效果最好。

To determine of physiological and biochemical indexes （ such as color, hardness, rot-ting rate, soluble solids, respiratory rate, peroxidase （ POD） and polyphenol oxidase （ PPO） activity ） of strawberry, we conduct the treatments with strawberry under concentration of 1%chitosan and citric acid of different concentration （2%, 3%, 4% and water ） different concen-tration of 1% chitosan and citric acid of different concentration （2%, 3%, 4%） during storage at for 5 days. Experimental results showed that chitosan treatments have better fresh effects for strawberry in the storage The treatment with chitosan coating can decrease the degree of brown-ing, slow down the softening and reduce the rotting rate. The respiratory rate of the sample by chitosan coating is increased from 32. 65ml/（kg·h）, 33. 59ml/（kg·h）, 32. 31ml/（kg·h） to 69. 98ml/（kg·h）, 62. 42ml/（kg·h）, 64. 63ml/（kg·h）respectively, from o day to the fifth day, by comparing with the control sample reaching 83. 98ml/（kg·h） at the fifth day, the treatment of 1% - chitosan - 4%citric acid have the best fresh-keeping effect. remarkable compared with the control sample reached 83. 98ml/（kg·h） at the fifth day, the treatment of 1% - chitosan - 4%citric acid have the best effect.