Chemical analysis
The cellulose and hemicellulose contents and composition
hereof in raw and silage treated crops was measured based on
NREL chemical analysis [21]. The ethanol concentration and
glucose, xylose, and arabinose were quantified by HPLC (Biorad
HPX-87H column, 63 C, eluent 4 mmol dm3 H2SO4) from
which the content of original glucan, xylan and arabinan was
calculated. Starch was determined according to [22]. Fructose
content was quantified by HPLC (Biorad HPX-87P column,
85 C, eluent water).