Automated Quality Evaluation System for Net and Gross Sugarcane Samples Using near Infrared Spectroscopy

Sugar content is the most important index of sugarcane quality in the payment system. A quality evaluation technique for shredded sugarcane was investigated using an automatic and high-speed near infrared (NIR) spectroscopy system. In this study, net and gross canes were tested in order to assess the potential for labour saving and cost reduction by the NIR measurement. NIR reflectance spectra ranging from 1100 nm to 2498 nm were collected to evaluate the cane quality of the shredded cane. A calibration equation for the pol in cane (PIC) of net cane was developed using a modified partial least squares (MPLS) regression. The accuracy of the PIC calibration for net cane was satisfactory with standard errors of prediction (SEP) of 0.21% and a bias of −0.06% in the range 1100–1848 nm wavelength. To eliminate the trash removal, a PIC calibration for gross cane was also examined. Results of the PIC calibration in the 1100–1848 nm wavelength range showed the highest accuracy (SEP=0.46%, bias=0.01%), although the accuracy for gross cane was lower than that for net cane. The NIR instrument could be used as an evaluation tool for the quality of net and gross sugarcane in a practical payment system.