Phenolic composition of Xinomavro (vitis vinifera L.cv.) grapes from different regions of Greece

Abstract

Context and purpose of the study – Phenolic compounds are located in skins and seeds and are responsible for important sensory and quality attributes of red grapes and wines, such as astringency, bitterness and colour. However, little is known regarding Greek varieties.The aim of this study is to evaluate the grape phenolic content and to present data that characterize the red grape variety Xinomavro (Vitis Vinifera L. cv.) from different wine regions of Greece.

Material and methods – In this study berry attributes, skin and seed content of phenolic compounds of 18 grape samples from four different regions in Greece, namely Naoussa, Amyntaino, Goumenissa and Rapsani were analyzed. Skins and seeds were removed from berries and different solvents were used in them for the extraction of anthocyanins and tannins. For tannin estimation, the protein precipitation assay using bovine serum albumin was employed. Anthocyanins were determined in skins by High-performance liquid chromatography (HPLC).

Results – According to the results, significant differences were observed in berry weight among the different regions, however the distribution of berry components in mature berries, % skin per berry and % seed per berry weight ratio, had no difference between the samples. The contribution of skins and seeds in berry were 8.1% and 2.6%, respectively. The higher content of total tannins and total anthocyanins in berries were observed in grapes from Amyntaio region. Grapes from Naoussa region had the lower concentrations of skin tannins and total anthocyanins. Finally, the lower concentrations of seed tannins were determined in Goumenissa grapes.