Physicochemical Properties and Antioxidant Profile of a Fermented Dairy Beverage Enriched with Coffee By-Products

Functional beverages are increasingly sought as components of a healthy diet, and goat milk offers a nutritious base with unique sensory attributes. This study aimed to develop a novel fermented goat milk beverage enriched with spent coffee grounds (SCG) extract, utilizing SCG’s high natural antioxidant content to improve nutritional and functional properties. SCG was extracted via aqueous solid–liquid extraction and lyophilized; its extract was incorporated into goat milk–fructose blends at 0%, 1%, and 2% (w/v). Analyses included physicochemical characterization (pH, acidity, fat, and protein), total phenolic content, and antioxidant capacity via DPPH assay, alongside consumer sensory evaluation for acceptance and purchase intent. Results demonstrated that higher SCG extract levels significantly increased pH, phenolic concentrations, and radical scavenging activity while reducing titratable acidity. The 2% SCG formulation achieved the highest overall, taste, and aftertaste acceptance and purchase intention. These findings suggest that SCG-enriched goat dairy beverages are feasible functional foods with enhanced antioxidant properties and consumer appeal, promoting valorization of coffee by-products.