Chemical tissue heterogeneity of young Arabidopsis stems revealed by Raman imaging combined with multivariate data analysis

•Raman imaging revealed chemical heterogeneity in context with plant microstructure.•Spectra analysis included 3 different algorithm and a plant spectral database.•Primary and secondary plant cell walls as well as the cell contents were investigated.•Fitting the spectrum of every pixel by reference spectra discriminated hemicelluloses.