Starch, a polymer of glucose units, functions as a sugar store in many plants. It is a mixture of two polysaccharides: amylose and amylopectin. You can obtain more information about starch at our
dedicated webpage for this constituent.
If starch analysis is not carried out then it is possible that, in our analysis packages for determining the
lignocellulosic sugars, some of the glucan could come from starch. However, if we do quantify starch then we subtract the starch content from the glucan content determined in those analysis packages ensuring, when
water soluble sugars are also removed by using one of our extraction packages, that the glucan content that we report comes from lignocellulose.
We follow a
Megazyme method for the determination of starch in biomass. Specifically, we use AOAC Official Method 996.11 for our analysis. This is very similar to the
NREL Laboratory Analysis Procedure 'Determination of Starch in Solid Biomass Samples by HPLC' (17/07/2005).
Biomass can contain water-soluble carbohydrates, many of which are listed under Celignis
Analysis Package P12. It is important that these are removed prior to our starch analysis as otherwise the water-soluble glucose could be inappropriately appropriated towards total starch content.
You can remove these sugars yourself via soxhlet extraction or you could use one of the Celignis Analysis Packages associated with the removal of extractives from a sample. These include
P5 - Water Extractives,
P6 - Full Extractives, and
P10 - Sugars, Lignin, Extractives, and Ash. If you would like the sugars in the extract to be determined then this is available in
P12 - Sugars in Solvent Extract.