Standard Test Method for Determination of Cellulose/Hemicellulose-Derived Glucan and Galactan Content in Solid Corn Biomass Samples

Abstract

4.1 The procedure, in brief, consists of solubilization of biomass using cold caustic extraction, an enzymatic removal of starch and yeast glucan followed by precipitation of hemicellulosic material, and acid hydrolysis of the residual carbohydrate pellet before measurement of glucose and galactose derived from cellulose and hemicellulose. 4.2 The starch removal procedure is identical to that employed in the NREL assay2 which was itself adapted from the Megazyme-published starch analysis procedure: RTS-NaOH, 2019.5,6 4.3 The cellulosic pellet hydrolysis and monosaccharide measurements are identical to those described in the NREL laboratory analytical procedure “Determination of Structural Carbohydrates and Lignin in Biomass,” NREL/TP-5100-42618 and “Determination of Cellulosic Glucan Content in Starch Containing Feedstocks,” NREL/TP-2800-76724.7 4.4 This test method references Practices E1757 and E3181. 4.5 This test method is intended for use in the measurement of the fermentable portion of cellulosic content in pre- and post-fermentation corn biomass specifically for the apportionment of a percentage of the total ethanol produced in a fermentation as cellulosic.