Sustainable sources need reliable standards
This review discusses the challenges within the research area of modern biomass fractionation and valorization. The current pulping industry focuses on pulp production and the resulting cellulose fiber. The hemicellulose and lignin are handled as low value streams for process heat and regeneration of process chemicals. The paper and pulp industry have therefore developed analytical techniques to evaluate the cellulose fiber while the other fractions are given low priority. In strive to use also the hemicellulose and lignin fractions of lignocellulosic biomass, moving towards a biorefining concept, there are severe shortcomings with current pulping and also in the analysis of biomass. Lately, new fractionation techniques have emerged which valorize a larger extent of the lignocellulosic biomass. This progress has disclosed the shortcomings in analysis of mainly the hemicellulose and lignin structure and properties. To move the research field forward, analytical tools for both the raw material targeting all wood components and the generated fractions, as well as standardized methods for evaluating and reporting yields are desired. At the end of this review a discourse on how such standardizations can be implemented is given.