Optimization of Malted Sorghum Protein Extraction by Response Surface Methodology

Abstract

Four independent variables viz. ultrasonic power, pH, extraction time and solvent/meal ratio were selected. The extraction process was evaluated by a selected response like protein yield and the second-order model obtained revealed 96.7% of coefficient of determination. Selected response, which evaluated the extraction process, was protein yield and the secondorder model obtained for protein yield revealed a coefficient of determination of 96.7%. The optimal extraction conditions for protein were determined as follows; Ultrasonic power, pH, extraction time and solvent/meal ratio were 400W, 8.0, 40min, and 20:1 (v/w) respectively. Protein yield was primarily affected by Ultrasonic power, pH and solvent/meal ratio. These conditions resulted in protein yield of 5.43g of soluble protein from extract/100 g malted sorghum flour, which was agreed closely with the predicted value 5.36%. The adequacy of the model was confirmed by extracting the protein under optimum values using the model. These results may help in designing the process of optimal protein extraction from malted sorghum flour. J. Food Sci. Technol. Nepal, Vol. 6 (53-58), 2010 DOI: http://dx.doi.org/10.3126/jfstn.v6i0.8260