Ethanol production from waste pizza by enzymatic hydrolysis and fermentation

Abstract

In this work, the feasibility of ethanol production from waste pizza (WP) by enzymatic hydrolysis and fermentation was investigated. The effects of enzyme volumes (0.02-0.08 mL/L) and WP mass ratios (50−160 g/L) on the performance of enzymatic hydrolysis and ethanol fermentation were also examined. It was observed that the lowest enzyme volume (0.02 mL/L) could completely hydrolyze WP with mass ratio of 50 g/L. The reducing sugar (RS) increased obviously with increasing of WP mass ratio from 50 g/L to 160 g/L when the enzyme volume of 0.02 mL/L was applied. The WP hydrolysate was utilized as substrate for bio-ethanol production with the highest cumulative ethanol production of 27.58 g/L and ethanol yield of 0.292 g/g WP, respectively. To our knowledge, this is the first study to report ethanol production from WP by enzymatic hydrolysis and fermentation.