Grape water: reclaim and valorization of a by-product from the industrial cryoconcentration of grape (Vitis vinifera) must.

Abstract

The term 'grape (Vitis vinifera) water' refers to a by-product from the cryoconcentration of must that, if not reclaimed, would be considered as wastewater. In this study, the nutraceutical potential of waters reclaimed from the cryoconcentration of Grillo and Moscato musts was evaluated. Both waters showed physicochemical parameters in agreement with Italian regulation for drinking water, and interesting levels of F- (3.02-8.02 mg L-1 ) and SO4 - (52.85-49.34 mg L-1 ). Inorganic elements, including Mg (5.54-7.78 mg L-1 ), K (47.12-59.87 mg L-1 ), Fe (219.09-205.32 μg L-1 ), and Zn (189.65-127.30 μg L-1 ), and phenolic contents <35 mg GAE L-1 contributed to determine moderate antioxidant activities. Considering fatty acid composition, oleic and linoleic acids predominated, being higher in Moscato than Grillo samples (64.42% versus 58.22%, and 5.42% versus 6.07%). Grape waters displayed also rich aroma profiles, including mainly esters, alcohols and terpenoids. The latter components (i.e. linalool and α-terpineol) were more abundant in Moscato than in Grillo (13% versus 8%). Interestingly, some minor volatiles, characterized the vine of provenance (e.g. benzaldehyde and 3-methylbutylacetate in Moscato). All grape waters showed also a considerable fraction of ethyl lactate, six-carbon compounds and acetates, reflecting the proximity of samples to the grapes of origin. In a growing scenario of environmental decay and resource depletion, results from this study support an innovative and profitable waste recycling strategy for the wine industry. © 2020 Society of Chemical Industry.