engleski

The effect of drying method and sample preparation on supercritical CO2 extraction of grape seed oil

After winemaking process great quantities of grape pomace is remained. Grape pomace consists of grape stalks, seeds and skins. It is considered as waste, but it can be used as fertilizer, source of energy, fiber, oil, proteins for animal feed and bioactive compounds. In this study supercritical CO2 extraction of oil was carried out from grape seeds of three grape varieties (Graševina, Zweigelt and Cabernet sauvignon). Quality of obtained oil and fatty acids composition were determined as well as protein and fibre content in defatted cake after supercritical extraction. The aim of this study was to monitor the influence of drying method (naturally (ND) and chamber (CD) drying) and sample preparation (seeds screened, seeds screened and washed, seed screened after drying from grape pomace) on supercritical CO2 extraction of grape seed oil. Highest oil content was obtained from ND screened and washed seeds of red variety Cabernet sauvignon sample (14.85%) and lowest from CD screened seeds of white variety Graševina sample (7.67%). Peroxide value ranged from 0.36–1.77 mmol O2/kg of oil, free fatty acids 0.28–8.0%, and insoluble impurities 0.05– 0.28%, depending on grape seed variety, sample preparation and drying method. Determined fatty acids in oil were palmitic, stearic, oleic and linoleic acid ranged 6.98–11.58%, 3.82–6.59%, 14.90–19.97% and 61.82–71.96% in ND seeds and 6.84–8.68%, 4.12–5.73%, 15.10–20.18% and 67.88– 70.76 in CD seeds, respectively. In defatted cakes protein and fibre content ranged 8.17– 9.85% and 34.58– 43.96%, respectively.

drying ; grape seed oil ; supercritical CO2 extraction ; defatted cake

nije evidentirano