acid soluble lignin

A small fraction of the lignin in a biomass sample is solubilized during the hydrolysis process of the acid insoluble lignin method. This lignin fraction is referred to as acid soluble lignin and may be quantified by ultraviolet spectroscopy. (Source Ehrman, T. Determination of Acid-Soluble Lignin in Biomass. NREL-LAP-004. Golden, CO: National Renewable Energy Laboratory, September 9, 1996.)