Comparison of the chemical composition of grape seed oil extracted by different methods and conditions

Grape seeds are the main byproduct of the grape-processing industry and contain oil with a high content of high-quality compounds. In this sense, grape seed oil extracted using Soxhlet, pressing and ultrasound was evaluated in relation to its physicochemical properties, fatty acid composition, antioxidant capacity, degree of unsaturation and critical properties. Interesting values of antioxidant capacity by oxygen radical absorbance capacity assay were obtained for lipophilic and hydrophilic extracts (ca 24-67 and ca 2-7 mu mol ET g(-1) of oil, respectively). The composition of the grape seed oil varied with the methods of extraction, as expected, with a higher content of linoleic acid in the extraction by pressing due to the absence of the temperature effect in the process. The bis-allylic position and oxidizability indexes were high for pressing, Soxhlet and ultrasound extraction. Grape seed oil content extracted from Cabernet Sauvignon and Ives species ranged from ca 7% to ca 18% with highest concentrations of saturated, mono- and polyunsaturated fatty acids of 187, 124 and 698 mg per gram of oil, respectively, and the highest oil content obtained in the ultrasound-assisted extraction was under conditions of 50 degrees C, 60 min and solvent-to-seed ratio of 1:8. (c) 2023 Society of Chemical Industry (SCI).