速溶藏茶制备工艺优化、功能性成分及抗氧化性分析

张恒; 郑俏然; 何靖柳; 韦婷; 刘翔; 章斌

doi:10.13386/j.issn1002-0306.2020070363

速溶藏茶制备工艺优化、功能性成分及抗氧化性分析

Optimization of Preparation Technology of Instant Tibetan Tea and Analysis of Its Functional Components and Antioxidant Activity

摘要

摘要: 为制备速溶藏茶，本研究以速溶藏茶得率、藏茶多糖提取量和藏茶茶多酚提取量为指标，通过单因素实验和响应面试验优化了速溶藏茶浸提工艺，并进一步研究了冷冻干燥和喷雾干燥对速溶藏茶中功能性成分和体外抗氧化活性的影响。结果表明，藏茶最佳浸提条件为料液比1:53 （g/mL），温度98.5 ℃，浸提时间1.5 h，浸提次数3次，此时速溶藏茶得率为29.72%±0.13%，藏茶多糖提取量为6.06±0.03（g/100g），藏茶茶多酚提取量为6.27±0.05（g/100g）利用UHPLC-QqQ-MS/MS检测出冷冻干燥和喷雾干燥的速溶藏茶中均有10种功能性成分，EGCG、GA、GCG、ECG为速溶藏茶主要功能性成分，且冷冻干燥的速溶藏茶中EGC、EGCG和槲皮素含量更高（P<0.05）。冷冻干燥速溶藏茶对DPPH自由基和ABTS自由基清除能力的IC₅₀分别为0.247、0.417 mg/mL；喷雾干燥速溶藏茶对DPPH自由基和ABTS自由基清除能力的IC₅₀分别为0.339、0.443 mg/mL，可见，速溶藏茶具有较好的抗氧化活性。

Abstract: To prepare instant Tibetan tea, the extraction technology was optimized by single factor experiment and Box-Behnken response surface design, with the yield of instant Tibetan tea, the extraction of polysaccharide and the extraction of polyphenols as the evaluation index.The results showed that the optimal extraction conditions were as follows: solid-liquid ratio 1:53 (g/mL), extraction temperature 98.5 ℃, extraction time 1.5 h, and extraction 3 times. Under the optimal extraction conditions, the yield of instant Tibetan tea was 29.72%±0.13%, the extraction of polysaccharide was (6.06±0.03) g/100 g, and the extraction of Tibetan tea polyphenols was (6.27±0.05) g/100 g. Ten kinds of functional components in instant Tibetan tea were detected by UHPLC-QqQ-MS/MS, EGCG, GA, GCG and ECG were the main catechins. The contents of EGC, EGCG, quercetin in freeze-dried instant Tibetan tea were higher than those in spray-dried instant Tibetan tea (P<0.05). The IC₅₀ of freeze-dried instant tea on scavenging ability of DPPH and ABTS free radicals were 0.247 and 0.417 mg/mL, and the IC₅₀ of spray-dried instant tea on scavenging ability of DPPH and ABTS free radicals were 0.339 and 0.443 mg/mL. Therefore, the instant Tibetan tea powder has good antioxidant activity.