In the pretreatments
using dilute acid and steam explosion the changes in the
compositions of the solid phases are due to the hydrolysis of hemicellulose
and in a lesser proportion to the cellulose hydrolysis. This
was evidenced by the presence of glucose, xylose, arabinose, acid
acetic acid, furfural and hydroxymethyl furfural in the liquid fraction
obtained after the pretreatments.