The basis of this invention consists of the formation of microemulsions from a polar antioxidant-rich fraction in an oily medium, specifically in edible oils. These microemulsions are characterized in that their stability and homogeneity makes them suitable to incorporate them in different foods or pharmaceutical products. The most novel factor of this invention is that the critical micellar concentration (CMC) is attained by vacuum elimination of the excess polar solvent, which is the antioxidant matrix, leaving part of this solvent in the microemulsion, acting as co-surfactant.