Processing technologies, phytochemical constituents, and biological activities of grape seed oil (GSO): A review

The grape seed is one of the most valuable constituents of grape pomace, a by-product generated during winemaking. Using grape seed as a raw material to develop valuable products will contribute to the recycling and reuse of grape pomace, as well as to the sustainable development of the wine industry. The grape seed oil (GSO) is rich in bioactive compounds with various health-promoting properties and has great potential application in the pharmaceutical, cosmetic, and food industry. In this review, we first elaborate on the processing technologies of GSO in terms of requirements for raw materials, current extractive technologies, and oil stability. In the second part, we summarize the characteristics of GSO phytochemical compounds, such as fatty acids, phytosterols, vitamin E, and phenols. Finally, we focus on recent studies related to the GSO biological activities, including antioxidant, anti-inflammatory, and metabolic disease alleviation. In addition, the latest developments of GSO products and their derived foods are also illustrated concisely. For the product design of GSO, the key may be to fully exploit and utilize the inherent characteristics of grape seed to produce functional oil with high phenol content, which requires further improvements in the extraction and storage strategy of GSO, as well as increasing the lipid solubility of phenolic compounds. In terms of technology, designing more environmentally friendly, efficient, and low-cost processes and equipment for making GSO is also a trend. Concerning physiological activity, studies combining lipidomics, proteomics, metabolomics, and nutriomics may provide further insights into the mechanisms of the health benefits induced by GSO.