Abstract: In order to improve the extraction rate of β-1,3-glucan from yeast paste, response surface methodology was used for the optimization of alkaline extraction conditions. The effects of NaOH concentration, extraction time and extraction temperature on the extraction rate of β-1,3-glucan were explored by single factor tests. Subsequently, a regression model was established using a central composite design. Based on the model, response surface analysis was conducted to explore optimal extraction conditions. The results indicated that the optimal extraction process parameters were NaOH concentration of 2.05%, extraction temperature of 92.70 ℃ and extraction time of 2.50 h. Under these optimal extraction conditions, the extraction rate of β-1,3-glucan was up to 15.76%, which was consistent with the predicted value of 15.82%. Therefore, the extraction rate of β-1,3-glucan were enhanced by response surface methodology.

Key words: β-1,3-glucan, beer yeast paste, response surface methodology (RSM), extraction process