Cell wall degrading enzymes from various microbial sources were previously reported in degradation of high gravity mashes and pulps from various grains and roots, suggesting their potential for the VHG process. A mixture of commercial cellulase from Trichoderma reesei and hemicellulases and -glucanases from Humicolainosolens was used for viscosity reduction of ethanol fermenta-tion residues (vinasse) from wheat. Product analysis showed that enzymatic hydrolysis of arabinoxylan, -glucan, and cellulose hadoccurred in the substrate [24]. The use of -glucanases was also demonstrated for viscosity reduction of barley and oat mash [25].Cell wall of dicotyledonous plants contains high content pectin(30–50%), which resulted in high gelling capacity and high viscosity of mash compared to that of monocotyledonous origins [26].Various cell wall degrading enzyme activities including pectinase(polygalacturonases), xylanase, cellobiohydrolases and mannanase have been shown to reduce viscosity of root mashes [11]. Viscosity of sweet potato mash was decreased by treatment with xylanase [13] and cellulase from T. reesei [27]. The developed VHG processusing xylanase-pretreated sweet potato root mash has been imple-mented in pilot and industrial scale [28]. Pectinase was shown tobe the major activity for viscosity reduction in potato, in which itsefficiency could be increased by synergistic action with hemicellulases and cellulases [14]. The combination of alkaline treatment(0.1 N Na OH) and enzymatic hydrolysis was also reported to lead to greater reduction of viscosity in sugar beet mash by demethylation and deacetylation of pectin, resulting in a remarkable decrease in enzyme dosage to achieve the operating viscosity [15].