Determination of the Effects of Adding Milk and Sugar on the Antioxidant Capacity of Oolong Tea by Chemical and Cell Culture-Based Antioxidant Assays

• Main Authors: Angkana Wipatanawin, Sudarat Phongsawanit, Thadthanan Maneeratprasert, Sittiwat Lertsiri, Pawinee Deetae
• Language: English
• Published: Science Faculty of Chiang Mai University 2019
• Subjects: tea; milk; sugar; sweetener; cellular antioxidant activity; FIC; ABTS; CAA
• Online Access: http://it.science.cmu.ac.th/ejournal/dl.php?journal_id=5955; http://cmuir.cmu.ac.th/jspui/handle/6653943832/66145
• Institution: Chiang Mai University

The effect of sugars and/or milk on the antioxidant capacity of Oolong tea was evaluated using 2,2´-azino-bis 3-ethylbenzothiazoline-6-sulfonic acid diammonium salt (ABTS), ferrous ion-chelating (FIC) and cellular antioxidant activity (CAA) assays. The addition of sugar did not alter the antioxidant capacity of tea (p < 0.05), however with the addition of sweetener an 18% and 14% increase was observed using ABTS and FIC assays respectively. In contrast, using the CAA method, the sweetener decreased the tea antioxidant capacity by 8%. Milks and milks and sugars decreased the antioxidant capacity of tea by 30% and 45% respectively determined by ABTS and CAA assays, with an opposite result using the FIC method. The chemical and cellular based methods showed poorly correlated values.