Diversity of Seed Flavan-3-Ols in Croatian Native Grapevine Cultivars (Vitis vinifera L.) Grown in Coastal Region

Abstract

Seed extracts are becoming more important due to their beneficial biological activities. The main constituents of seed extracts are flavan-3-ols, compounds important in winemaking. The coastal region in Croatia is rich in native grapevine varieties, which are used in wine production. The aim of the research was to analyze the flavan-3-ol profiles of 20 native varieties, and to evaluate the potential use of grape seeds as a source of flavan-3-ols. The flavan-3-ols from seeds were analyzed by HPLC. The predicted yield of flavan-3-ols was calculated using the analyzed profiles. In total, eight compounds were identified, with the most abundant compounds being catechin, epicatechin, and procyanidin B2. In general, the red grape varieties had higher content of flavan-3-ols than the white varieties, which was confirmed by PCA. The coastal region could potentially yield up to 73.97 kg/ha of flavan-3-ols, depending on the variety. The results show the diversity of flavan-3-ol profiles among Croatian varieties and their potential usage as a source of valuable nutraceuticals.