Nekvapil Jiří, Sumczynski Daniela, Salek Richardos Nikolaos, Bučková Martina
Department of Food Analysis and Chemistry, Faculty of Technology, Tomas Bata University in Zlín, Vavrečkova 5669, 760 01 Zlín, Czech Republic.
Department of Food Technology, Faculty of Technology, Tomas Bata University in Zlín, Vavrečkova 5669, 760 01 Zlín, Czech Republic.
Nutrients. 2024 Nov 26;16(23):4058. doi: 10.3390/nu16234058.
BACKGROUND/OBJECTIVES: This study tested the influence of in vitro digestion on the release of organic acids and low molecular weight saccharides of matcha.
The concentrations of analytes in the raw and undigested portion of matcha were measured using HPLC with spectrometric and refractometric detection to establish their residual values after a two-step enzymatic digestion that was finally presented as a retention factor.
It was established that dry matter digestibility values after simulated gastric and both gastric and intestinal phases were 67.3 and 85.9%, respectively. Native matcha, citric acid (44.8 mg/g), malic acid (32.2 mg/g), trehalose (36.1 mg/g), and L-arabinose (8.20 mg/g) reached the highest values and were predominant, whereas D-fructose, xylose, maltose, and saccharose were not detected. Regarding gastric phase digestion, succinic and malic acids, trehalose and D-glucose were the worst-releasing compounds and their remaining factors reached 34, 19, 18, and 50%, respectively, whereas L-arabinose was completely released. Focusing on gastric and small intestinal digestion, the least-releasing compounds of matcha tea leaves were succinic acid and trehalose, with their retention factors at 7 and 13%, which can proceed with the leaf matrix to the large intestine.
Malic, oxalic, and citric acids, the carbohydrates D-glucose, L-arabinose, and L-rhamnose, are almost entirely released from matcha tea during digestion in the stomach and small intestine and can be available for absorption in the small intestine. In the measurement of oxalic acid, considering that the process of shading tea leaves increases the concentration of this acid and its retention factor value is too small, it would be appropriate in the future to evaluate the recommended maximum daily intake of matcha tea for people sensitive to the formation of urinal stones.
背景/目的：本研究测试了体外消化对抹茶中有机酸和低分子量糖类释放的影响。
使用配备光谱和折光检测的高效液相色谱法测量抹茶原料和未消化部分中分析物的浓度，以确定经过两步酶消化后的残留值，最终以保留因子表示。
经测定，模拟胃消化阶段以及胃和小肠消化阶段后的干物质消化率分别为67.3%和85.9%。天然抹茶中，柠檬酸（44.8毫克/克）、苹果酸（32.2毫克/克）、海藻糖（36.1毫克/克）和L-阿拉伯糖（8.20毫克/克）含量最高且占主导地位，而未检测到D-果糖、木糖、麦芽糖和蔗糖。在胃消化阶段，琥珀酸和苹果酸、海藻糖和D-葡萄糖是释放最差的化合物，其残留因子分别达到34%、19%、18%和50%，而L-阿拉伯糖完全释放。关注胃和小肠消化，抹茶茶叶中释放最少的化合物是琥珀酸和海藻糖，其保留因子分别为7%和13%，它们可随叶片基质进入大肠。
苹果酸、草酸和柠檬酸，以及碳水化合物D-葡萄糖、L-阿拉伯糖和L-鼠李糖，在胃和小肠消化过程中几乎完全从抹茶中释放出来，可在小肠中被吸收。在草酸的测定中，考虑到遮荫茶叶的过程会增加这种酸的浓度且其保留因子值过小，未来对于对尿路结石形成敏感的人群，评估抹茶的推荐每日最大摄入量是合适的。
