研究了含不同质量浓度钙离子（0~100mg/L）的水对绿茶浸提茶汤的理化成分及感官品质的影响。研究结果表明,随着钙离子质量浓度的升高,浸提茶汤浊度增加,pH值下降;总固形物和氨基酸含量呈增加趋势,茶多酚和蛋白质含量呈下降趋势,而咖啡碱和黄酮化合物含量差异不显著;儿茶素EGC含量呈增加趋势,C、EGCG、GCG、ECG及CG含量都呈下降趋势,EC含量差异不显著;Al3+、Cu2+、Na+、Zn2+含量呈下降趋势,而K+、Mg2+、Mn2+含量呈增加趋势;茶汤感官品质下降,逐渐变浑浊,熟闷味加重,苦涩味增加。钙离子主要通过参与冷后浑形成、诱导儿茶素组分异构化及氧化分解反应等作用影响茶汤品质。
The effect of different Ca2+ concentration（0~100mg/L）on the chemical components and sensory quality of extracted green tea infusion was investigated. The results showed that, with the increasing of Ca2+ concentration, the turbidity of tea infusion increased, pH decreased; the contents of total solids and free amino acids increased, the contents of tea polyphenols and protein decreased, but there was no significant difference in the contents of caffeine and flavones; the contents of EGC increased, the contents of C, EGCG, GCG, ECG and CG decreased, but there was no significant difference in the contents of EC; the contents of Al3+, Cu2+, Na+, Zn2+ decreased, and the contents of K+, Mg2+, Mn2+ increased; tea infusion turned turbid, ripe and sulks odour enhanced, and bitter and astringency strengthened. The effect of Ca2+ on tea infusion quality maybe arisen by participating in tea cream formation, inducing epimerisation of catechins and appearing decomposition reaction.
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