Based on M.T. Holtzapple, in Encyclopedia of Food Sciences and Nutrition (Second Edition), 2003 (https://www.sciencedirect.com/topics/nursing-and-health-professions/acid-detergent-fiber#:~:text=Van%20Soest%20procedure,insoluble%20minerals%20(mainly%20silica)), the hemicellulose content of lignocellulosic material can be determined as the difference between Neutral Deterget Fiber (which contains hemicellulose, cellulose, lignin, and insoluble ash) and Acid Detergent Fiber (which contains cellulose, lignin, and insoluble ash).

With this, I understand that NDF (Van Soest method) removes from the biomass all soluble material (non-structural components that are non-chemically bound components of biomass such as sucrose, nitrate/nitrite, protein, ash, chlorophyll, waxesextractives; i.e. extractives).

However, extractives removal consist in solid-liquid extraction with an organic solvent (benzene:ethanol, toluene:ethanol, ethanol, acetone...) and sometimes, a second step with hot water for the removal of water-soluble compounds. For citing just a few authors:

• Sluiter, A., Ruiz, R., Scarlata, C., Sluiter, J., & Templeton, D. (2008). Determination of Extractives in Biomass: Laboratory Analytical Procedure (LAP); Issue Date 7/17/2005. January.
• Messaoudi, Y., Smichi, N., Bouachir, F., & Gargouri, M. (2019). Fractionation and Biotransformation of Lignocelluloses-Based Wastes for Bioethanol, Xylose and Vanillin Production. Waste and Biomass Valorization, 10(2), 357–367. https://doi.org/10.1007/s12649-017-0062-3
• Ayeni, A. O., Adeeyo, O. A., Oresegun, O. M., & Oladimeji, T. E. (2015). Compositional analysis of lignocellulosic materials: Evaluation of an economically viable method suitable for woody and non-woody biomass. American Journal of Engineering Research, 44, 2320–2847. www.ajer.org.

Messaoudi et al. (2019) characterize biomass feedstock with Van Soest method (NDF, ADF, cellulose and lignin content detrmination), but toluene:ethanol extractives removal for lignocellulosic fractionation.

My question is: why not using NDF solution for extractives removal or, conversely, solvent extractives removal followed by ADF for determining hemicellulose content ?

In other words: Could I use the same method (NDF or solvent removal of extractives) for both initial charaterization and later lignocellulose fractionation?