NIR measurement of specific gravity of potato

Near infrared (NIR) spectroscopy was investigated as a method for nondestructive measurement of specific gravity of potato. A total of 250 potatoes of three cultivars, Irish-Cobbler, May-Queen and Kita-akari, were used as experiment samples. The NIR spectra (700-1100 nm) of potato samples were acquired by the interactance method and partial least square (PLS) regression analysis was used to develop a predictive model for specific gravity. As a result, the model gave relatively good predictions of the specific gravity, with a correlation coefficient of 0.94 and standard error of prediction of 0.0044g/cm(3). The results show the potential of the NIR technique as a means for nondestructive measurement of specific gravity of potato with reasonable accuracy.