Application of encapsulated tomato by-product extract as a colorant in mascarpone

Agricultural by-products, often underutilized, represent a significant opportunity to obtain sustainable value-added products to develop new functional foods. In this context, the (typically discarded) aerial parts of tomato plants (Solanum lycopersicum L. var. cerasiforme), were studied as new sources of natural bioactive compounds, focusing the extraction and encapsulation (using spray drying with maltodextrin as the encapsulant) of chlorophylls. The encapsulated natural colorant was subsequently incorporated into mascarpone cheese to assess its stability and effect on nutritional and antioxidant properties. The obtained extracts were mainly characterized by high concentrations of bioactive compounds, particularly quercetin-3-O-deoxyhexoside (14.4 ± 0.3 mg/g). The colorant imparted a greener hue to the mascarpone (a* -6.0 ± 0.05 vs. -1.7 ± 0.05 in control, p < 0.001) and maintained antioxidant activity (OxHLIA EC₅₀ = 1440 ± 72 to 1166 ± 66 μg/mL, p = 0.030) without altering the nutritional profile (p > 0.05). Moreover, no cytotoxicity was observed, and the fatty acid composition remained unchanged. Accordingly, the studied encapsulated colorant might be used as a functional ingredient in other dairy products, imparting an attractive color while preserving nutritional integrity. In conclusion, the incorporation of TAPC is an effective strategy to enrich dairy products with natural pigments and bioactive compounds without compromising quality. Future research is needed to explore its application in other food matrices and assess long-term storage effects.