三种原料前处理方式对淮山罐头品质的影响

为解决热烫预处理易造成淮山罐头汤汁浑浊的问题,提高淮山罐头品质,分析比较热烫处理和以果葡糖浆为渗透液的真空渗透处理、常压渗透处理三种原料预处理方式对淮山罐头品质的影响。结果表明,热烫处理虽然能够钝化多酚氧化酶和过氧化物酶活性,从而起到较好的护色作用,但是会对淮山的表面组织结构造成严重破坏,导致电导率增加,硬度下降达34.80%。常压渗透和真空渗透处理组的淮山,由于糖液的渗入,结构更加致密,在罐头加工前处理时间内,并不会使样品发生明显褐变,对细胞膜的破坏程度均远低于热烫处理。常压渗透5 h和真空渗透3 h、4 h、5 h的淮山硬度均较新鲜淮山有所上升,但抗坏血酸含量明显下降;真空渗透处理组的淮山组织结构更完整,所制成淮山罐头的感官评分高于相同渗透时间的常压渗透处理组和热烫处理组。真空渗透脱水预处理能有效减少淮山罐头浑汤问题,提高罐头品质。

Effect of three pretreatment methods on the quality of canned Chinese yam

In this paper, the effects of three methods for material pretreatment on the quality of canned Chinese yam were analyzed and compared, which included blanching treatment, vacuum osmotic treatment and atmospheric osmotic treatment with fructose syrup as osmotic solution. The results showed that the blanching treatment group was able to inactive polyphenol oxidase and peroxidase, and thus had better color protection, but the structure of Chinese yam in blanching treatment group was seriously damaged and led to an increased conductivity, and its hardness decreased by 34.80%, while the structures of yam in atmospheric osmosis and vacuum osmosis treatment groups were denser due to the osmosis of sugar solution, the sample would not be significantly browned during the processing time before canning, and the damage to the cell membrane was much lower than vacuum osmotic dehydration. The hardness of Chinese yam in atmospheric osmosis at 5 h and in vacuum osmosis at 3 h, 4 h and 5 h were both higher than that of fresh Chinese yam, but ascorbic acid content decreased significantly. Moreover, the structure of Chinese yam in vacuum osmotic treatment group was more complete, and the sensory score of canned yam was higher than those of atmospheric osmotic treatment group with the same osmotic time and blanching treatment group. Vacuum osmotic dehydration is an effective way to solve the problem of canned soup turbidity and improve the quality of canned Chinese yam.