Oil content in grapevine seeds of intra- and interspecific provenance genotypes

The aim of this study was to determine and compare the oil content in grapevine seeds from intra- and interspecific genotypes with yellow-green and blue-violet berries. Grapevine processing generates secondary products that represent about 20% of the total processed mass among which grape seeds contain 9-20% oil, rich in antioxidants and essential fatty acids with biological importance for the human body. Owing to this composition, grape seeds serve as a valuable raw material for obtaining grape seed oil. The seeds were extracted from fresh berries at the onset of must fermentation, and oil content was determined using the nuclear magnetic resonance (NMR) relaxometry method. In intraspecific genotypes with yellow-green berries, oil content ranged from 13.8-13.7% ('Fetescă regală', 'Sauvigon'), while interspecific genotypes of the same colour group contained 13.45-14.46% oil ('‘Alexandrina’', 'Sarmis', etc.). For intraspecific genotypes of the same colour group contained 13.5% oil ('Fetească regală') and 16.6% oil ('‘Merlot’'), were recorded, whereas interspecific blue-violet genotypes showed oil contents between 11% ('‘Ametist’') and 15.35% (Sor). The results indicate that oil accumulation in grapevine seeds depends both on the genotype and on the climatic conditions in which the vines are cultivated. Climatic analysis of the cultivation area showed an increase of 3.23°C above the calculated long-term annual temperature norm, suggesting that arid conditions favour higher oil content compared with regions with moderate temperatures.