State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang West Road, Hefei, 230036, China.
School of Tea & Food Science and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei, 230036, China.
J Food Sci. 2021 Feb;86(2):327-333. doi: 10.1111/1750-3841.15571. Epub 2021 Jan 12.
Fresh tea leaves (Camellia sinensis; Chuanxiaoye) used to make tencha tea are a combination of the stem and leaf. Tencha made from the leaf alone is considered a high-quality tencha beverage with a seaweed-like aroma, mellow taste, and a green appearance. However, no study has investigated the differences between these two variants. In this study, the effects of stem removal on physicochemical properties and sensory quality of tencha beverage were investigated. The appearance feature, taste, and aroma were evaluated, and the results indicated that stem removal improved the quality of tencha beverages. The water extract, total free amino acids, total catechin, epigallocatechin gallate, caffeine, and chlorophyll were higher in leaf-only tencha (LOT) than in leaf and stem tencha (LST), whereas the crude fiber and phenol ammonia ratios were lower in LOT than in LST. Principal component analysis and hierarchical clustering analysis further discriminated between the tencha beverages with different stem contents. This study provided a theoretical basis for quality control by adopting a stem-leaf separation process in tencha manufacturing. PRACTICAL APPLICATION: This research provides theoretical guidance for improving tencha quality during manufacturing.
鲜茶叶（Camellia sinensis；川下叶）用于制作抹茶，是茎和叶的组合。只用叶子制成的抹茶被认为是一种高质量的抹茶饮料，具有海藻般的香气、醇厚的口感和绿色的外观。然而，尚未有研究调查这两种变体之间的差异。在这项研究中，研究了去除茎对抹茶饮料理化性质和感官质量的影响。评估了外观特征、口感和香气，结果表明去除茎可提高抹茶饮料的质量。仅用叶片制成的抹茶（LOT）的水提取物、总游离氨基酸、总儿茶素、表没食子儿茶素没食子酸酯、咖啡因和叶绿素含量高于叶和茎制成的抹茶（LST），而 LOT 的粗纤维和酚氨比低于 LST。主成分分析和层次聚类分析进一步区分了不同茎含量的抹茶饮料。本研究为在抹茶制造中采用茎叶分离工艺进行质量控制提供了理论依据。
