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 α-tocotrienol contents of oil samples extracted with cold-pressed change between 13.21 and 34.71 mg/100 g, α-tocotrienol contents of oils obtained by soxhlet system in all grape varieties varied between 8.89 and 33.89 mg/100 g. In addition, while ɣ-tocotrienol contents of cold-pressed oils range from 15.47 to 39.95 mg/100 g, ɣ-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.

Practical applications

Cold-pressed grape seed oil stands out as a suitable alternative to other commonly used vegetable oils because of its higher amounts of essential fatty acid, and many others bioactive compounds. Grape seed oil is being used in various fields such as cosmetics and cooking. Because the cold-pressing does not need both heat and chemical treatments, cold-pressed oils are being preferred for natural and safe food products by consumer. The consumption of vegetable oils rather than solid fats is crucial to maintaining health. As known, grape seed oil is an environment friendly oil due to a by-product of wine and grape juice-making processes.