The valorization of fruit by-products represents a sustainable strategy for developing functional foods. This study evaluated the incorporation of orange peel into kefir-based cream cheese as a value-added ingredient. Dried and ground peel was added at 1% and 5% (w/w), in non-fermented and brine-fermented forms, and its effects on physicochemical, microbiological, and functional properties were assessed. Orange peel enhanced texture and imparted a yellow–orange hue, slightly lowered pH, and increased titratable acidity, indicating improved acidification. Total phenolic content (50–300 mg GAE/100 g dw) and antioxidant activity (40–140 µmol TE/g dw) were markedly enhanced, supporting the potential of citrus by-products in functional dairy formulations.
Gusmão et al. (2026) studied this question.