ArticleFoods (Basel, Switzerland)2025
Determination of L-Theanine and Caffeine Contents in Tea Infusions with Different Fermentation Degrees and Brewing Conditions Using the Chromatographic Method.
Article in Foods (Basel, Switzerland), 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.
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Who cites it
4 citing papers in PubMed.
- Seasonal and processing differences in nonvolatile compounds and volatile aroma of teas from Zhaoyuan, China: insight into "spring green, summer black, autumn dark" quality pattern.Food chemistry: X · 2026Article
- Effects of L-theanine on cognition, mood and sleep: evidence from human trials.Frontiers in nutrition · 2026Review
- Unveiling Fermentation Effects on the Functional Composition of Taiwanese Native Teas.Molecules (Basel, Switzerland) · 2026Article
- From molecular mechanisms to translational applications: a parallel assessment of green and black tea modulation of oxidative stress.Nutrition & metabolism · 2025Review
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Authors and funding
2 authors.
Funding
Abstract
This study aimed to determine the caffeine and L-theanine contents in tea infusions prepared under varying fermentation degrees, brewing conditions (temperature and time), and serving methods (tea bag/loose-leaf). Infusions of six tea types (green, white, yellow, oolong, black, and Pu-erh) and various serving forms of green, white, and black tea were brewed at 80 °C and 100 °C for 2, 5, and 10 min. Contents were analyzed using reversed-phase high-performance liquid chromatography. Caffeine levels were highest in black and yellow tea (14 ± 1.0 mg/200 mL and 13.8 ± 0.2 mg/200 mL, respectively), both of which were significantly higher than the levels in green, white, and oolong tea (11 ± 2.1 mg/200 mL; 5.8 ± 0.7 mg/200 mL; and 4 ± 1.6 mg/200 mL, respectively;
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