不同粒径对抹茶体外消化特性及抗氧化活性的影响

Effects of Different Particle Size on the in Vitro Digestibility Characteristics and Antioxidant Activity of Matcha

文章对不同粒径的抹茶经体外消化后生物活性物质及抗氧化活性进行了比较分析。结果表明,粒径不会影响抹茶的水分、灰分及茶氨酸含量。与未消化抹茶相比,经胃消化后,抹茶中茶多酚、茶多糖和咖啡碱的含量分别增加了19.64%~29.52%、30.29%~41.13%、11.38%~20.00%。此外,经胃消化后,抹茶中总儿茶素类化合物含量较消化前增加了12.33%~33.95%,还能显著提升抗氧化活性。经肠消化后,抹茶中茶多酚、大多数儿茶素类化合物和抗氧化活性显著下降。相关性分析发现,茶多酚、表儿茶素、表没食子酸儿茶素和表没食子儿茶素没食子酸酯与抗氧化活性均呈显著正相关。综上,通过800目网筛的抹茶理化特征符合GB/T 34778—2007《抹茶》的要求,且经体外消化后酚类物质保留最多。该研究可为抹茶的精深加工提供科学指导。

This paper compares the bioactive substances and antioxidant activities of matcha with different particle size after in vitro digestion.The results showed that the particle size does not affect the content of moisture,ash and theanine in matcha.Compared to undigested matcha,gastric digestion increased the contents of tea polyphenols,tea polysaccharides and caffeine by 19.64%–29.52%,30.29%–41.13% and 11.38%–20.00%,respectively.In addition,after gastric digestion,the content of total catechins in matcha increased by 12.33%–33.95% compared with that before digestion,and the antioxidant activity was significantly improved.After intestinal digestion,tea polyphenols,most catechins and antioxidant activity in matcha significantly decreased.Correlation analysis showed that tea polyphenols,epicatechin,epigallocatechin and epigallocatechin gallate in matcha positively correlated with antioxidant activity.In summary,the physicochemical characteristics of matcha that through the 800-mesh screen met the requirements of GB/T 34778—2007 Matcha,and the phenolic substances were most retained after in vitro digestion.This study can provide scientific guidance for the in-depth processing of matcha.