Extraction of β-1,3-glucan from beer waste yeast

The enzyme-alkali extracting method for the β-1,3-glucan from beer waste yeast treated by ultrasonic waves was studied.Papain enzyme of 208 U/g substrate was added in the beer yeast and incubated for 8 h at pH 6 and 50 ℃.Protein removal rate was 62.82%.Protein hydrolysate(0.348 g/L) containing polypeptides and amino acids was recycled.The precipitate was treated with 30 mL 2% NaOH and water-bathed 5 h at 70 ℃.The yield of β-1,3-glucan was 11.00% by purity of 90.50%.