Source: Magness et al. 1971
Large quantities of grape seeds are available from grapes processed for wine, seeded raisins and grape juice. The seeds, up to 0.5 inch long, are enclosed near the center of the fleshy pulp. They contain about 12 percent of a drying oil. The oil is obtained by expression or with solvents. The oil, after refining, is used mainly for edible purposes. Oil from raisin grape seed is used for coating the raisins to improve appearance and keep them pliable. Grape seed oil is also used in industry.