Multiblock PLS as an approach to compare and combine NIR and MIR spectra in calibrations of soybean flour

When utilized alone, the MIR spectra gave models with considerably inferior prediction power and analytical figures of merit than NIR-based models. The multiblock methodology revealed to be very useful, since it helped to determine if there was distinctive information in each spectral data set and evaluate the relative importance of each data set. The results pointed out the existence of additional information in the MIR spectra not present in the NIR spectra. Although several works have already been reported comparing NIR and MIR spectroscopic techniques using different multivariate regression techniques, at the best of our knowledge none of them applied the approach of multiblock PLS. Therefore, the present work intends to explore this direction, using the NIR and MIR spectra as predictor blocks to model flour's properties in a parallel mode (MB-PLS) or in a serial mode (S-PLS).