Abstract:
The valorization of grape skins, a by-product of the wine industry, represents a viable strategy for developing functional foods aligned with sustainable production principles. This study aimed to incorporate grape skin powder into a Panna Cotta-type dessert and assess its influence on nutritional value, functional properties, sensory quality, and overall product safety. Formulations were prepared with four inclusion levels of grape skin powder: 1.0%, 2.5%, 5.0%, and 7.5%. Physicochemical analyses revealed that the addition of powder significantly influenced product characteristics. The total polyphenol content increased from 94.25 mg GAE/100 g in the control to 324.91 mg GAE/100 g at 7.5%, resulting in a corresponding enhancement of antioxidant activity (from 19.42% to 69.55% radical inhibition via DPPH assay). These improvements suggest a clear functional enrichment of the product with increasing powder concentration. Color parameters were also affected, with a pronounced intensification of red and violet tones, contributing to a more attractive appearance. In terms of texture, hardness increased moderately, while springiness remained within acceptable sensory thresholds, indicating a firmer yet still palatable consistency. Sensory analysis, showed that samples with 2.5% and 5.0% grape skin powder achieved the best balance between taste, texture, color, and overall acceptability. Higher concentrations, although richer in antioxidants, introduced slight bitterness and graininess that impacted the hedonic scores. Microbiological tests confirmed the absence of pathogens such as Escherichia coli, Salmonella spp., and Staphylococcus aureus, validating product safety. The study demonstrates that grape skin powder can be successfully incorporated into a dairy-based dessert, creating a novel functional product with enhanced antioxidant properties and good consumer acceptance. The results support a circular economy model and contribute to the development of clean-label, health-promoting foods derived from agro-industrial by-products.