Application of the Tea Polyphenols Composite Edible Membrane in Preservation of Pear

In this paper,the preservation effect of Korla pear after coating was studied. The effects of the addition of tea polyphenols and CMC,glycerol and the content and kinds of starch in edible composite membrane on the weight loss rate of pear were analyzed by single factor experiments. The tea polyphenols and CMC addition in edible membrane were studied by response surface experiment. The storage experiments were also carried out,and the hardness,soluble solids,titratable acids,and polyphenol oxidase activities of fragrant pears were tested by drying them in a drying oven at 30℃ for 45 min. The results showed that after 30 d of storage at 30℃,when corn starch of 5 g was added to 100 mL deionized water,the addition amount of glycerin was 1 g and that of tea polyphenols was 3 g,the added amount of CMC was 0.3 g,the weight loss rate of korla pear treated with coating preservative was 4.33%±0.2%。In the storage experiment,the hardness and titratable acid contents of the pear in the coated group decreased more slowly than that in the uncoated group with the prolonged storage time,but the values in the coated group and the uncoated group showed an increasing trend in the determination of soluble solids and polyphenol oxidase activity,while the values in the coated group increased more slowly than those in the uncoated group. The fruits of the coated group were intact within 30 d,while those of the uncoated group were rotten and deteriorated within 20 d. So that the tea polyphenols composite edible membrane would have a good effect on the preservation of pear,and it could effectively prolong the freshness of pear.