Optimization of ultrasound assisted extraction of protein from sunflower meal and its physicochemical and functional properties

This research aimed at improving the protein extraction process from sunflower meal using the Box-Behnken design to get the optimal ultrasonic extraction conditions, based on yield of protein and consumed energy. The optimal extraction points were observed at power density (220 W/L), temperature (45 degrees C) and extraction time (15 min). Under optimum UAE conditions, the measured yield of protein and energy consumed values were 54.26% and 0.13 kW hr, respectively. The observed values for these responses were found to be comparable to the predicted values created by the mathematical models. Functional and physicochemical characteristics of protein isolate were estimated at the optimal points. The protein content, particle size, bulk density and water and oil holding capacities were 934.92 g/kg(d.b), 627.6 nm, 0.372 g/mL, 0.985 g(water)/g(protein) and 2.06 g(oil)/g(protein), respectively. The highest solubility, emulsifying activity (EA) and emulsion stability (ES) were 74.59, 5245, and 50.45% respectively and were obtained at pH 9.0.