Effect of cold press and soxhlet extraction systems on fatty acid, tocopherol contents, and phenolic compounds of various grape seed oils

In this study, fatty acids, tocopherol contents, and phenolic compounds of the grape seed oils obtained with cold-pressed and soxhlet extraction systems from several grape seeds were investigated. Linoleic acid contents of cold-pressed oils varied between 59.61 and 72.13%. In addition, linoleic acid contents of oils obtained with soxhlet system changed between 58.51 and 71.17%. While gamma-tocotrienol contents of oil samples extracted with cold-pressed change between 13.21 and 34.71mg/100g, gamma-tocotrienol contents of oils obtained by soxhlet system in all grape varieties varied between 8.89 and 33.89mg/100g. In addition, while gamma-tocotrienol contents of cold-pressed oils range from 15.47 to 39.95mg/100g, gamma-tocotrienol contents of soxhlet extraction oils in all grape varieties were determined between 13.47 and 35.75 mg/100 g. Both systems' oils are rich in catechin, gallic acid, and chlorogenic acid. While catechin contents of cold-pressed oils change between 427.80 and 847.14 mg/kg, catechin contents of soxhlet extraction oils in all grape seeds ranged from 537.11 to 836.88 mg/kg.