ArticleMolecules (Basel, Switzerland)2021
Effect of Water Hardness on Catechin and Caffeine Content in Green Tea Infusions.
Article in Molecules (Basel, Switzerland), 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers, 2 of them syntheses that pooled it.
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Who cites it
14 citing papers in PubMed, 2 syntheses or guidelines pooled it, 31 citations in OpenAlex.
- Tea and liver fibrosis: a bibliometric analysis of mechanisms, translational challenges, and emerging trends.Frontiers in nutrition · 2026Pooled it
- Anti-Influenza with Green Tea Catechins: A Systematic Review and Meta-Analysis.Molecules (Basel, Switzerland) · 2021Pooled it
- Compositional Diversity and Functional Interactions of Bioactive Compounds in Japanese Green Tea: Focus on Matcha, Sencha, and Gyokuro.Molecules (Basel, Switzerland) · 2026Review
- Matcha as a Source of Bioactive Compounds: A Review of Health-Promoting Properties and Potential Applications.Nutrients · 2026Review
- Marine Klebsiella sp. RR1-mediated AgNPs functionalized with matcha: synthesis, characterization, and evaluation of antibacterial, antioxidant, anti-inflammatory, and gene regulation of breast cancer potentials.Microbial cell factories · 2026Article
- Deciphering the Flavor Chemistry, Processing and Quality Evaluation Methods of Milk Tea: A Comprehensive Review.Foods (Basel, Switzerland) · 2026Review
- Association of tea consumption with all-cause/cardiovascular disease mortality in the chronic kidney disease population: an assessment of participation in the national cohort.Renal failure · 2025Article
- Development of Pretreatment Approaches for Authentic Representation of Tea Infusion Aroma.Foods (Basel, Switzerland) · 2025Article
- Stress-Relieving Effects of Japanese Green Tea: Evaluation Using the Molar Ratio of Caffeine and Epigallocatechin Gallate to Theanine and Arginine as an Indicator.Foods (Basel, Switzerland) · 2025Article
- Effects of Green Tea Extract Epigallocatechin-3-Gallate on Oral Diseases: A Narrative Review.Pathogens (Basel, Switzerland) · 2024Review
- Effect of the type of brewing water on the sensory and physicochemical properties of light-scented and strong-scentedFood chemistry: X · 2024Article
- Tea film formation in artificial tap water.Soft matter · 2023Article
- Quality characteristics of green Tea's infusion as influenced by brands and types of brewing water.Heliyon · 2023Article
- Bibliometric and visual analysis in the field of tea in cancer from 2013 to 2023.Frontiers in oncology · 2023Article
Corrections and comments
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Authors and funding
6 authors at 1 institution in 1 country.
Funding
Abstract
The health benefits of green tea are associated with its high catechin content. In scientific studies, green tea is often prepared with deionized water. However, casual consumers will simply use their local tap water, which differs in alkalinity and mineral content depending on the region. To assess the effect of water hardness on catechin and caffeine content, green tea infusions were prepared with synthetic freshwater in five different hardness levels, a sodium bicarbonate solution, a mineral salt solution, and deionized water. HPLC analysis was performed with a superficially porous pentafluorophenyl column. As water hardness increased, total catechin yield decreased. This was mostly due to the autoxidation of epigallocatechin (EGC) and epigallocatechin gallate (EGCG). Epicatechin (EC), epicatechin gallate (ECG), and caffeine showed greater chemical stability. Autoxidation was promoted by alkaline conditions and resulted in the browning of the green tea infusions. High levels of alkaline sodium bicarbonate found in hard water can render some tap waters unsuitable for green tea preparation.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.