1. A method of determining calibration training spectra for a spectrometer, the method comprising: analyzing a continuous stream of spectra acquired during a calibration training mode; logging unique spectra required to build a chemometric calibration model; determining if a new spectrum is unique within the set of calibration training spectra by comparing the new spectrum to each of the existing calibration training spectra; calculating a residual spectrum by subtracting the scaled new spectrum from the existing calibration training spectrum; calculating a residual score for the new spectrum for each of the existing calibration training spectra; sorting the residual scores to identify the minimum residual score; and identifying the calibration training spectrum that is the closest match to the new spectrum using the minimum residual score.