Decoding the Taste Profile of Chardonnay Marc Through Sensory-Directed Fractionation

Chardonnay marc, a winemaking coproduct consisting of grape skins, seeds, and stems, shows potential as an upcycled food ingredient with possible health-promoting properties and distinctive flavor. Although its aroma chemistry has been comprehensively studied, the taste chemistry remains unexplored. Herein, 39 taste-active compounds were identified through sensory-directed fractionation using solid-phase extraction, sequential liquid-phase extraction, and preparative reverse-phase high-performance liquid chromatography, followed by sensory analysis. Dose over threshold (DOT) calculations indicated fructose and glucose contributed to sweetness, whereas tartaric, glucuronic, gluconic, and malic acids imparted sourness. Astringency was driven by 4 flavonol glycosides, with quercetin-3-O-rutinoside being most influential. A taste simulation model formulated from sensory-active compounds with DOT > 1 closely matched the taste profile of Chardonnay marc. This study provides insight into taste-active compounds of Chardonnay marc and lays a foundation for future research on processing effects, flavor optimization, and the broader valorization of food industry coproducts.