A second life for wine grapes: Discovering potentially bioactive oligosaccharides and phenolics in chardonnay marc and its processing fractions

Chardonnay Marc as a New Model for Upcycled Co-products in the Food Industry: Concentration of Diverse Natural Products Chemistry for Consumer Health and Sensory Benefits

“…Mean intakes for both flavanols and epicatechin were estimated at 260 and 36 mg/day, respectively . While encapsulated cocoa flavanol intake can certainly achieve these levels of intake, a combination of foods within a healthy diet such as apples, berries, wine, and tea may also provide similar flavanol levels. , For PBNP ingredients such as Chardonnay marc, with estimated epicatechin levels at approximately 0.9 mg/g, and up to 9 mg/g in the seeds, a daily serving of 2 teaspoons can provide up to 20% of the mean predicted flavanol intake level achieved by individuals in the EPIC cohort …”

“…However, some known tastants and chemosensory-active molecules have been reported from grapes, including from Chardonnay. These include the sour tasting organic acids (i.e., succinic, malic, citric, and tartaric acid), , the bitter flavan-3-ols and procyanidins, ,,,− and velvety astringent flavanol glycosides (i.e., quercetin-3- O -α- d -glucopyranoside) ,, (Figure ). In addition, amino acids and sugars with known taste activities have been reported. , Although, there have been no systematic studies reported on the taste chemistry of Chardonnay marc, based on the unique sensory attributes that it imparts to foods, along with its unique combination of potentially health promoting molecules, Chardonnay marc is a promising source of sensory-active molecules.…”

“…PBNPs present in wine grape marc also include a complex carbohydrate fraction that can significantly impact both the health properties and sensory attributes of the material. Dietary fiber is a collective term for nonstarch and nondigestible polysaccharides, which includes the noncarbohydrate lignin, composed of phenolic compounds covalently bound to polysaccharides. − The general class of PBNP dietary fiber is complex with its definition constantly debated and refined, primarily due to the constraints and limitations in analytical chemistry, which impede a proper characterization and quantification of its individual components . In an effort to harmonize the nomenclature, the Institute of Medicine (IOM) defined dietary fiber as nondigestible carbohydrate and lignin that is intrinsic and intact in plants, functional fiber as isolated nondigestible carbohydrate that has a functional physiological effect in humans, and lastly, total fiber as the sum of dietary and functional fiber .…”

“…Five oligosaccharides were unique to the seed but not the seedless marc, while nine additional oligosaccharides were unique to the seedless marc and not the seed. Further analysis of the monosaccharide building blocks of the oligosaccharides indicated that seedless marc oligosaccharides consisted of 11 units that were 81% hexose, predominately (72%) from glucose, with lower amounts of galactose and mannose . Of interest, the monosaccharide fucose (which is one of the prototypical components of HMOs) was detected at a level of 3.65% followed by arabinose, glucuronic acid, galacturonic acid, ribose, and rhamnose.…”

“…Lignin contributes to the seed's woody structure and was 7fold greater in the seed component compared to marc without seed (364 mg/g dw versus 52 mg/d dw, respectively). 43 While pectin characterization was not part of that study, a recent optimization of pectin extraction from Chardonnay marc produced a polysaccharide fraction containing 55.7% homogalacturonan and 35.2% rhamnogalacturonan I (RG-I) with short chains or single units of arabinose and galactose (RG-1). 55 Unlike other dietary components, the impact of dietary fiber on health is not dependent on its absorption and distribution to the tissues, but rather its impact on the alimentary tract, interaction with other dietary components, and the gut microbiota.…”