萝卜低盐腌制过程中脆度变化原因探究

Reasons for brittleness changes of radish during pickling process with low-salt content

蔬菜腌制过程中,随着腌制时间的延长,其质地逐渐变软。该研究通过检测萝卜腌制过程中水分、食盐、总酸、乙醇不溶物等含量的变化,研究多聚半乳糖醛酸酶、纤维素酶活性随腌制时间与脆度变化之间的关系,并观察不同腌制时期萝卜的组织微观结构变化。结果显示,腌制萝卜样品的脆度随着腌制时间的延长呈不断下降的趋势,总酸含量与脆度呈显著负相关(P<0.05),水分含量与脆度间相关性较低(P>0.05)。原果胶、乙醇不溶物、木质素与萝卜脆度呈显著正相关(P<0.05)。纤维素含量与脆度相关性较低(R2为0.832 3)。萝卜腌制过程中纤维素含量由2.96%降至2.34%,变化幅度较小。腌制萝卜扫描电镜结果表明,随着腌制的进行,其细胞壁逐渐皱缩、塌陷。

During the pickling process, the texture of vegetables gradually becomes soft as the pickling time prolonged. In this study, the relationship between polygalacturonase and cellulase activity and the changes of pickling time and brittleness was studied by detecting the changes of water, salt, total acid and alcohol-insoluble residue （AIR） contents in the radish pickling process. The microstructure changes of radish in different pickling periods were observed as well. The results showed that the brittleness of pickled radish samples showed a decreasing trend with the prolongation of the pickling time, and the total acid content was significantly negatively correlated with the brittleness （P〈0.05）, and the correlation between water content and brittleness was low （P〉0.05）. There was a significant positive correlation between the protopectin, AIR and lignin and the crispness of radish （P〈0.05）. The correlation between cellulose content and brittleness was low （R^2=0.832 3）. The content of cellulose decreased from 2.96% to 2.34% during the pickling process, and the variation range was small. The results of scanning electron microscopy of pickled radish showed that the cell wall gradually shrinked and collapsed with the pickling process.