Polyphenolic profile and in vitro biological activity of Serbian orange (skin fermented white) wines

Orange wines are made from white grapes, but with prolonged skin contact during fermentation. Available data on their composition and potential health benefits are limited, so polyphenolic profile (HPLC analysis) and in vitro biological activities (enzyme inhibition, antioxidant, and anti-inflammatory) of 24 Serbian orange wines were analyzed, including the correlation between determined composition and bioactivities. The wines displayed distinct polyphenolic profiles, enabling partial differentiation based on overall polyphenol content, including dominant components (catechin, gallic and caffeic acids), along with occasional occurrences of anthocyanins. However, no discernible distinctions were noted based on grape varieties, vintage, or producer. All twenty-four orange wines showed a reasonable inhibition of digestive enzymes and lipid peroxidation, twenty-one samples reduced ROS generation in the cell-based assay, but only two suppressed both PGE₂ and TXA₂ production in U937 cells, implicating possible functional food properties. No significant correlation between polyphenolic profile and determined biological activities was noticed.