The very high lignin removals achieved with the alkaline
pretreatments cannot be correlated with the amount of reducing
sugars obtained in the enzymatic hydrolysis. The dispersion of
the remaining lignin directly affects the enzymatic attack. A
highly-dispersed remaining lignin, even in low contents, could hinder
the enzyme access to the amorphous portions of cellulose that
composes the grass fibers, thereby affecting the enzymatic hydrolysis
efficiency.