Extraction of oil enriched in a-tocopherol from grape seed (Vitis Vinifera) using supercritical carbon dioxide

a-tocopherol is one of the most important natural anti-oxidizing agent. Obtaining an oil enriched with this molecule by means of a renowned clean process could be very important for the food industry that could use it for fortification. In this work, milled grape seeds (Vitis vinifera), a residue obtained from the wine industry, were extracted with supercritical carbon dioxide (SC-CO2) as solvent, to determinate the optimal extraction conditions to obtain an a-tocopherol enriched oil. All the extractions were carried out at the pressure of 25 Mpa, based on earlier extraction of oil enriched in a–tocopherol from other seed matrices. Both total oil and a-tocopherol extracted from milled grape seeds were determinated as a function of particle size (0,85mm<d1=1,4mm, 0,425mm<d2=0,85mm, 0,3mm<d3=0,425mm), temperature (40, 80°C) and CO2 to seed mass ratio (25, 60, 90). The optimal extraction conditions were determined considering the maximum concentration of a-tocopherol in the extracted oil.