Oil from seeds of various grape cultivars grown in Southern Poland and its antioxidant properties

Abstract

In Poland seeds from grape are a waste product that is not used as a source of valuable substances for humans. The main aim of this study was to obtain and analyze the oil from the seeds of seven grape cultivars from the Garlicki Lamus vineyard located in Garlica Murowana (near Krakow, Poland, coordinates: 19º56’E, 50º08’N). Our work is presenting estimation of the percentage content of oil and fatty acid composition derived from cultivars of grape seed (Leon Millot, Jutrzenka, Bianca, Regent, Seyval Blanc, Marechal Foch, Sibera). In samples the following fatty acids have been determined: C18:2 from 76.69 % (Bianca) to 81.33 % (Marechal Foch), C18:1 from 10.67 % (Marechal Foch) to 14.15 % (Sibera), C16:0 – from 5.05 % (Seyval Blanc) to 7.40 % (Bianca), C18:0 (stearic acid) from 2.10 % (Sibera) to 3.16 % (Seyval Blanc). On the other hand, the lowest concentration was found for C18:3, the presence of which in measurable amounts was found in four of the seven analyzed vine varieties (Bianca, Regent, Seyval Blanc, Sibera). Also the percentage of the oil obtained from the seeds of the analyzed samples was measured. The maximal concentration of oil was obtained for Sibera (12.70 ± 0.88 %) cultivar and the smallest for Marechal Foch (6.48 ± 0.49 %). Seeds obtained from grape pomace can provide excellent raw material for the oil, which can be used in many branches of industry. Extracts from the oil were tested for the content of total polyphenols level from 34.7mg·l-1 (Marechal Foch) to 85.1 mg·l-1 (Seyval Blanc) and total antioxidant status, which was determined by the FRAP (Ferric Reducing Antioxidant Power) method from 19.72 μmolFe2+·l-1 (Marechal Foch) to 817.64 μmolFe2+·l-1 (Sibera). In addition, antioxidant capacity was measured, using the method of reduction of DPPH radical reduction. The lowest activity was measured for Regent (4.65 %) and the highest for Marechal Foch (11.62 %). There has also been strong antioxidant potential for two of the seven studied grape seed cultivars – Seyval Blanc and Sibera.