Studies on Physical,Chemical Properties and Antioxidant Activities of Red Oolong Tea

• Main Authors: Wu, Zheng-Xian, 吳政憲
• Other Authors: Lee ,Shih-Chieh
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/33894982009077122623

碩士 === 大葉大學 === 生物產業科技學系 === 101 === In this study, using the Tai-tea No. 12 and Dah Yeh Oolong，were used to made of Tai-tea No. 12-38、Tai-tea No. 12-63、Tai-tea No. 12-65、Dah Yeh Oolong No. 61、Dah Yeh Oolong No. 72，respectively. General physical and chemical analysis of tea、color values、antioxidant activities and HPLC catechins and total changes of plate number for teas testes were measured. Physical and chemical analysis of partial results have shown that water content and pH values were no significant difference in five kinds of teas. Based on color analysis,L value to that of Tai-tea No. 12-65 has the highest and brightest colors; Tai-tea No. 12-65 has smallest brightest colors and greenish color; b value to that fo Dah Yeh Oolong No. 72 has the highest and the yellow side values. The determination of antioxidant activities indicated that total polyphenol content for Tai-tea No. 12-38 was the highest. Its DPPH radical scavenging ability also was the highest which has 60.02% scavenging ability in 600.2 mg dry weight among all five tea samples tested. In addition to that, Tai-tea No. 12-38 have the best test results among five teas in reducing power, ABTS radical scavenging effect. Tai-tea No. 12-63 has the best chelating ability of ferrous ions effect, 79.41％ in 794 mg dry base. Catechins contents in Red Oolong tea were qualitative and quantitative analyzed by HPLC. The amount of tatol catechin contents were approximation equal to that of Tai-tea No. 1238 and Dah Yeh Oolong No. 61. On the contrary, Dah Yeh Oolong No. 72 has the lowest catechins contents. Based on the these results,in the five kinds of tea tested, Tai-tea No. 12- 38 was best in antioxidant activities in catechin content.