In this study, three brands of green tea collected from different markets of Rawalpindi, Pakistan were screened to identify best brewing method for green tea preparation and characterize their antioxidant potential. Brand A, brand B and non-branded green tea were examined for antioxidant potential by DPPH (1,1-Diphenyl-2-picrylhydrazyl) radical scavenging assay and reducing power method. Samples were prepared by ten different recipes used in different cultures. Distilled water and ethanol was used as solvent. Three brewing methods with highest, lowest and moderate antioxidant activities were identified and analyzed for phytochemical constituents such as phenolic compounds, flavonoids, tannins, saponins, proteins, alkaloids and steroids. Cold cocktail showed highest antioxidant activity (85.9%), soft infusion showed moderate (70.6%) while hard infusion indicated lowest antioxidant potential (59.9%) amongst all the green tea brands tested. Phenolic compounds, tannins and proteins were found in all tea types with varying strength due to different brewing method. Alkaloids were not present in any type of green tea while steroids were found in brand A and B.
Key words: Camellia sinensis; phytoconstituents; antioxidant assay; brewing methods; cold cocktail
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