Grape seeds: the heart of Vitis vinifera L. and their phenolic composition in different grape varieties

Abstract

Vitis vinifera L., is a species of Vitis, native in many geographical areas all over the world, with thousand varieties. Grape seeds “ The heart of Vitis vinifera” has nutritional and medicinal value and its history is intimately entwined with the history of wine. They are waste product of the winery and grape juice industry. They contain protein, lipid, carbohydrates, polyphenols including catechin, epicatechin, gallic acid and procyanidin and have been associated with a whole slew of health benefits, like , cardiovascular and anticancer health benefits – due to strong antioxidant properties of polyphenols, fat loss benefits and a natural remedy for depression. Scientific studies have shown that the antioxidant power of grape seeds proanthocyanidins is 20 times greater than vitamin E and 5- times greater than vitamin C. The aim of this research was to analyze polyphenols in grape seeds of 15 grape varieties, five white -Muscat of Alexandria-Muscat of Samos-Assyrtiko-Athiri-Savatiano, five red, Kalampaki-Xinomavro-Liatiko- Kotsifali and five French varieties, Cabernet Franc, Syrah, Chardonnay, Merlot and Cabernet Sauvignon, cultivated in Greece, in their physiological maturity, using HPLC chromatography after solvent extraction of grape seeds. The higher content of polyphenols was found in the seeds of the red Kalampaki grape variety and Merlot red French variety cultivated in Greece and the lower content in the seeds of Savatiano-white grape variety.