The demand for natural pigments in the food industry is increasing. Color and stability of anthocyanins of chagalapoli (Ardisia compressaK.) fruit added to an isotonic beverage as microcapsules and free extract were evaluated at two temperatures (4 and 25 °C) in the absence of light. Anthocyanins degradation followed first-order kinetics in the evaluated conditions. The stability of anthocyanins, measured by the variables reaction rate (K), half-life time (t1/2), and anthocyanin retention (AR), was affected significantly (p< 0.01) by temperature. At the end of storage at 4 °C, AR was 91.2 ± 0.28% and 89.63 ± 0.22% in the beverages with microcapsules (BM) and with anthocyanins from extract (BE), respectively, without a significant difference (p≥ 0.05) between them. However, at 25 °C, AR in the BM was 53.72 ± 0.27%, a significantly lower value (p≤ 0.05) than that in BE (58.83 ± 1.37%). The color difference values (ΔE) in beverages stored at 4 °C were 3.81 and 2.17 for BM and BE, respectively, while at 25 °C, it was 8.57 and 8.21, respectively. The most stable anthocyanin was cyanidin 3-galactoside. Chagalapoli anthocyanins, both as microcapsules or as an extract, are adequate for adding natural color to isotonic beverages.