Characterization of Oil Obtained from Grape Seeds Collected during Berry Development

Abstract
The surpluses of the wine industry that originate from wine production in the European countries must be reduced. Green harvesting, consisting in collecting the grapes when they are still green, could contribute to the reduction of the yield of vineyards. The green grapes are not suitable for wine production, but they can be used for seed oil extraction. Grape seed oil is a linoleic acid rich oil that has been suggested as an alternative to traditional vegetable edible oils. In this work, grape samples were collected at different stages during berry development for seed oil extraction. The grapes collected at a very early stage showed a very low oil extraction yield compared with that of the samples collected at later stages. The oil from the grapes collected at an early stage had considerably higher sterols content and had a significantly different fatty acid composition compared with those of the oil extracted from grapes collected at later stages. However, the oil samples from grapes collected before veraison did not show significant differences with samples collected after veraison as regards oil extraction yield, fatty acids composition, and total sterol content and composition. Our data suggest that grapes collected from green harvesting near veraison could be suitable for seed oil extraction, with characteristics similar to those of the oil extracted from the seeds of mature grapes.