Methods of processing lignocellulosic biomass using single-stage autohydrolysis and enzymatic hydrolysis with C5 bypass and post-hydrolysis

A method of processing lignocellulosic biomass comprising:

• Pretreating a soft lignocellulosic biomass feedstock at a pH between 3.5 and 9.0 in a single-stage pressurized hydrothermal pretreatment reactor to very low severity such that the pretreated biomass has a xylan number of 10% or higher, wherein exogenous cellulase enzymes are not added during the pretreatment, and the pretreating does not comprise adding sulphuric acid to the feedstock;
• Separating the pretreated biomass into a solid fraction and a liquid fraction;
• Hydrolysing the solid fraction using enzymatic hydrolysis catalysed by an enzyme mixture comprising endoglucanase, exoglucanase, B-glucosidase, endoxylanase, xylosidase, and acetyl xylan esterase activities, wherein the enzyme mixture is not added to the liquid fraction;
• and
• Subsequently mixing the separated liquid fraction and the hydrolysed solid fraction;
• whereby xylo-oligomers in the liquid fraction are degraded to xylose monomers by action of enzyme activities remaining within the hydrolysed solid fraction.