Cellulase is a multi-component enzyme system that acts synergistically to degrade cellulose into glucose. It is composed mainly of exo-β-glucanase, endo-β-glucanase and β-glucosidase. Cellulases can be classified into endoglucanases, exoglucanases, and β-glucosidases which work together to break down cellulose. Cellulase has important applications in food processing by softening plant tissues and increasing juice yields, as well as in brewing by aiding barley germination and improving filtration efficiency.