Ultrasound-Assisted Extraction of Oil and Antioxidant Compounds from Wheat Germ and the Obtention of Protein and Fiber-Rich Residue

Wheat germ (WG) oil is highly used in cosmetics and pharmaceutics for its high tocopherol content. The present study explored and optimized the ultrasound-assisted extraction of oil and bioactive compounds from stabilized wheat germ at a laboratory scale. Optimum conditions were 15 s, 36% amplitude, and 10:1 solvent-to-solid ratio. The yield (5.1%) and the ether-soluble fraction (87.92%) obtained were remarkable considering the short extraction time, and the solvent used was absolute ethanol. Sonication did not have a significant impact on oil oxidation parameters (acidity and peroxide value), tocopherol content (1499 μg toc/g extract), and antiradical scavenging activity of the extracts (71% DPPH loss). The total fiber content (16%) and type of the remaining solids were not affected as well. Protein solubility increased with sonication. Altogether, these findings propose ultrasound-assisted extraction of oil from wheat germ as a promising alternative to conventional techniques.