Utilization of grape pomace as a value-added phenolic component for oat milk production

Abstract Grape pomace (GP), a wine industry byproduct rich in dietary fibre and polyphenols is used in this study to increase the nutritional, phytochemical, and sensory qualities of oat milk. Lactose-intolerant people, vegans, and health-conscious customers drink oat milk because it is plant-based, dairy-free, and sustainable product. Although rich in β-glucan and minerals, typical oat milk lacks phenolic compounds and antioxidant capability, limiting its functional dietary potential. In this work, GP extract was incorporated into oat milk to improve its bioactive profile, stability, and sensory appeal, addressing the growing market demand for plant-based functional beverages. The study evaluated the impact of GP fortification on phenolic composition, antioxidant activity, and consumer acceptance. Physicochemical research suggests oat milk has stable emulsion characteristics at a pH of 6.77±0.12 and titratable acidity of 0.43±0.21. Bioactive components increased significantly with GP supplementation, according to phytochemical profiling. After adding 0.2% GP to plain oat milk, the total phenolic content (TPC) increased from 35.08±2.30 mg GAE/g DW to 101.43±25 mg GAE/g DW, while the total flavonoid content (TFC) increased from 69.56±1.5 to 180.11±18 mg QE/g DW, consquently antioxidant activity increased to 48±8 mM Trolox/g DW. The anthocyanin concentration increased significantly, showing GP's potential to transport phenolic chemicals. On a nine-point hedonic scale, 0.2% GP-fortified oat milk had the highest consumer acceptability in flavour, colour, aroma, mouthfeel, and overall acceptability. Higher concentrations (0.3% and 0.5%) had stronger flavours and deeper colours, reducing acceptability. The results indicate that GP fortification, especially at 0.2%, enhances oat milk's nutritional and functional profile while keeping its taste. This study promotes grape pomace as a sustainable, value-added ingredient for plant-based functional beverages, boosting circular economy and health-conscious food innovations.