Processing biomass

A method comprising:

• (a) obtaining an electron beam irradiated cellulosic or lignocellulosic biomass, wherein the irradiated biomass material is prepared by irradiating said biomass material to at least 5 Mrad of ionizing radiation from an electron beam and wherein said irradiating reduces the biomass' cellulose number average molecular weight (Mn) from a Mn of 200,000 to 3,200,000 daltons before said irradiation to a Mn of 10,000 to 200,000 daltons after said irradiation;
• (b) inoculating the irradiated biomass material with a microorganism of the genus Trichoderma selected to utilize the irradiated biomass material to produce an enzyme;
• (c) maintaining the inoculated biomass under a fed-batch fermentation process and under conditions that allow the microorganism of the genus Trichoderma to produce the enzyme.