| Anthocyanins are water-soluble pigments, which are found abundantly in plants. However, anthocyanins are unstable and break due to several factors. The stability of anthocyanins could be increased by applying co-pigmentation with the addition of flavonoids, polyphenols, alkaloids, amino acids, organic acids, or self-association. This study aimed to observe the effect of co-pigmentation with catechin from Indonesian gambier (Uncaria gambir) to enhance the stability and antioxidant activity of black rice anthocyanin in isotonic sports drink during storage. Anthocyanins extracted from black rice (30 mg/L) were used for isotonic sports drink formulation. The addition of 0.1 µg/L catechins to the drink with catechin: drink ratio (1:1) significantly increased antioxidant activity (89.30±1.12%). In a storage period of one month at room temperature (25oC), anthocyanin content and antioxidant activity in isotonic sports drinks showed a significant decrease than that at 4oC. Catechin co-pigmentation in the drinks increased anthocyanin stability and antioxidant activity compared to that of control (drinks without catechin). In conclusion, co-pigmentation with catechin derived from Indonesian gambier could be applied to enhance the stability and antioxidant activity of black rice anthocyanin in isotonic sports drink during storage at cold temperature (4oC) for one month. |