Sustainable extraction methods for the recovery of polyphenolic compounds from grape pomace and its biological properties: a comprehensive review

Grape pomace (seeds, skin, and stalks) holds promise as a feedstock for various industrial applications. This comprehensive review describes advancements in sustainable and novel extraction processes for recovering polyphenolic compounds and their biological properties. In contrast to traditional methods, sustainable extraction techniques such as microwave-assisted, ultrasound-assisted, pressurized liquid, enzyme-assisted, and hydrothermal processes have been applied to produce high-quality and safe extracts. These methods utilize non-toxic solvents, maintain moderate temperatures, achieve fast extraction times, and require low energy input. The polyphenolic compounds, particularly flavan-3-ols, anthocyanins, and proanthocyanidins extracted from grape pomace, exhibit a wide range of biological properties, including anti-inflammatory, anti-obesity, antioxidant, antidiabetic, hepatoprotective, anticancer, antimicrobial, and heart health-promoting effects. They also contribute to enhancing the gut microbiota population, promoting health. In conclusion, emerging extraction methods offer a sustainable approach to producing bioactive compounds from grape pomace for use in the cosmetic, pharmaceutical, and food industries.