Tan Hui-Ling, Ojukwu Moses, Lee Le-Xuan, Mat Easa Azhar
School of Hospitality and Service Management, Sunway Universiti, 47500, Petaling Jaya, Selangor, Malaysia.
Food Technology Division, School of Industrial Technology, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia.
Heliyon. 2022 Dec 26;9(2):e12638. doi: 10.1016/j.heliyon.2022.e12638. eCollection 2023 Feb.
The influences of four types of brewing waters including tap water (TAP), alkaline ionized water (ALK), magnetized water (MAG) and mineral water (MIN), and two brands of commercial green tea (L and T) on quality characteristics of tea infusions were studied. The Oxidation Reduction Potential (ORP) values of the brewing waters was TAP > MAG, MIN > ALK. After brewing, all infusions showed a significant drop (p < 0.05) in pH values. The pH of original brewing waters of ALK (8.64) was the highest as compared to other waters, whereas L-MIN (pH 6.63) and T-MIN (pH 5.82) showed the highest pH values after brewing. Overall, the quality characteristics of green tea infusions were influenced by the brands of tea and the types of brewing water used. MAG was the most superior brewing water in extracting the green tea. Evidenced by total phenolic and flavonoids contents, both L-MAG and T-MAG infusions were superior in extracting antioxidative compounds as compared to other tea infusions. In addition, T-MAG infusion was the least astringent (P < 0.05) and scored the highest (P < 0.05) overall acceptability ( by sensory panelists.
研究了四种冲泡水（包括自来水（TAP）、碱性离子水（ALK）、磁化水（MAG）和矿泉水（MIN））以及两个品牌的商业绿茶（L和T）对茶汤品质特性的影响。冲泡水的氧化还原电位（ORP）值为TAP＞MAG，MIN＞ALK。冲泡后，所有茶汤的pH值均显著下降（p＜0.05）。与其他水相比，ALK原冲泡水的pH值最高（8.64），而L-MIN（pH 6.63）和T-MIN（pH 5.82）冲泡后的pH值最高。总体而言，绿茶茶汤的品质特性受茶叶品牌和所用冲泡水类型的影响。MAG是提取绿茶最优质的冲泡水。从总酚和黄酮含量来看，L-MAG和T-MAG茶汤在提取抗氧化化合物方面均优于其他茶汤。此外，T-MAG茶汤的涩味最轻（P＜0.05），总体可接受性评分最高（P＜0.05）（由感官评价员评定）。
