Effects of Refrigerated Storage on Lactic Acid Bacteria Viability and Antioxidant Activity of Goat Milk Yogurt Fortified with White Rice Bran Flour

White rice bran flour is a potential functional ingredient due to its dietary fiber and antioxidant compounds. This study evaluated the effects of refrigerated storage on the viability of lactic acid bacteria (LAB) and antioxidant activity of goat milk yogurt fortified with white rice bran flour. Goat milk yogurt supplemented with 4% white rice bran flour was stored at 4°C for 0, 1, 2, 3, and 4 weeks using a completely randomized design with four replications. LAB viability was determined by the Total Plate Count method, while antioxidant activity was measured using the DPPH assay and expressed as IC₅₀ values. Data were analyzed using one-way ANOVA followed by Duncan’s test. Storage period significantly affected LAB viability and antioxidant activity (p < 0.05). LAB counts decreased from 2.57 × 10⁷ CFU/mL at week 0 to 4.90 × 10⁶ CFU/mL at week 2, although a slight increase occurred at week 3. Antioxidant activity increased during storage, indicated by a decrease in IC₅₀ values from 226.85 to 64.98 μg/mL. Refrigerated storage reduced LAB viability but enhanced antioxidant activity. Storage for up to two weeks is recommended to maintain the functional quality of white rice bran-fortified goat milk yogurt.