Total phenol content and antioxidant activity (FRAP method) of six varieties of Iranian Tea

In this study، antioxidant activity and total phenolics of six tea type were analysed during various brewing time. For this purpose، Green، Kalemoorchei، Telepofaki، Chakoshsabz، Pashekaste، and red tea were brewed from 2 min up 10 min. Total antioxidant activity was determined as ferric reducing/antioxidant power (FRAP) assay. Total phenol content was determined using spectrophotometric technique، based on the Folin-Ciocalteau reagent and calculated as Gallic acid equivalents. The results showed the extraction of phenols increased with brewing time specially، up to seven minute and after that increased slowly. Total phenolic of black tea was more than red tea but less than green tea. Green tea followed with Kalemoorchei had the highest amount of phenol content (6. 076 & 5. 629 mM/g). The lowest amount was related to red tea (2. 234 mM/g). The brewing time had most effect on extraction total phenolics in black tea types. The antioxidant measurements showed that Chakosh-sabz tea and Taleh-pofaki had the highest and the lowest antioxidant activity، respectively.