2.4.1 Model Development for Principal Component Analysis
MVA routines, including Principal Component Analysis (PCA), were applied to the vibrational spectra acquired for each sample. The models were created using The Unscrambler ® X 2018 CAMO Software (0349 Oslo, Norway) version 10.5.1. Using OriginPro 8.6.0 (Northampton, MA, USA), Spectral analysis for unprocessed raw data was made. Several pre-processing methods were applied to the raw data. Standard normal variate (SNV), Multiplicative scatter correction (MSC), Savitzky-Golay first derivative (SG1), and Savitzky-Golay second derivative (SG2). These processing methods were applied to each data set, including combinations to separate the classes.