Development of a Sample Set for Soya Bean Calibration of near Infrared Reflectance Spectroscopy

The potential application of near infrared (NIR) spectroscopy is limited since its calibration equations are not always transferable from one instrument to another. Hence, an attempt was made to develop a selected sample set of soya beans with analytical data, which could be distributed to collaborators to calibrate their instruments. Sixty soya bean samples, (1 kg each) were selected and packed (200 g each) in laminated film bags after thorough mixing. During their storage at 4°C, the soya bean samples were periodically evaluated by chemical analysis as well as by NIR spectroscopy. Chemical compositions (i.e. moisture, protein and fat) were determined using conventional methods. Experimental results showed that no significant differences were found in the compositions of interest as well as in the reflectance spectra over a storage period of up to three years, and that the NIR spectroscopy method is independent of the location and model of the instruments. The experiment demonstrated that it is possible practically to use a pre-packed sample set with chemical data for calibration purposes.