2.2. Pre-treatments and hydrolysis of WBY
Pre-treatment of dry waste beer yeast was performed by mixing WBY with 100 mL of distilled water in a 250 mL round-bottom flask to reach a final concentration of 5%, 10%, 15% and 20% (w/v) respectively, which were regarded as untreated WBY mixed liquor. Four methods were investigated to treat WBY mixed liquor and details of the treatment procedures were as follows: