Abstract:In this study，black tea residue was used as the raw material and was pretreated using ultrasound waves combined with alkaline hydrogen peroxide. The effects of ultrasound time，volume fraction of hydrogen peroxide，ultrasound temperature，and NaOH mass concentration on the enzymatic hydrolysis of the tea residue to prepare reducing sugar were investigated. The results showed that under the conditions of ultrasound time of 30 min，ultrasound temperature of 80 ℃，NaOH mass concentration of 0.5%，and H2O2 volume fraction of 0.2%，the black tea residue was pretreated and then enzymatically hydrolyzed，resulting in a reducing sugar yield of 19.63%. The application of ultrasound waves combined with alkaline hydrogen peroxide to pretreat black tea residue could effectively improve the yield of reducing sugar prepared by enzymatic hydrolysis of black tea residue.