Optimization of extraction conditions of barley β-glucan by oxidation with hydrogen peroxide and heat treatment

In this study, response surface methodology was employed to optimize conditions for the extraction of barley β-glucan. A central composite experimental design was applied to investigate the effects of hydrogen peroxide concentration (X1: 0.2-0.8%), temperature (X2: 90-150 °C), and time (X3: 5-35 min) on the extraction of both total and soluble β-glucan. As a result, the highest total β-glucan content was 7.52% at a peroxide concentration of 0.451%, a temperature of 120 °C and an extraction time of 22 min, and this value was greatly influenced by X1 (P < 0.001). The highest soluble content was 6.31% at 0.444%, 105 °C, and 21 min. This extraction was affected by X1 (P < 0.001) and X2 (P < 0.001). With increasing X1 and X2 values, β-glucan content decreased and β-glucan purity increased. Our study showed that oxidation with hydrogen peroxide followed by heat treatment is an efficient and high-yielding method for the extraction of high-purity β-glucan from barley.