Prediction of internal compositions change in potato during storage using visible/near-infrared (Vis/NIR) spectroscopy

Visible/Near-infrared (Vis/NIR) spectroscopy at a range of 450-1000 nm was used to predict the values of three qualitative variables (starch, reducing sugar, and moisture content) on 200 potato tubers from 2 potato genotypes ('Agria' and 'Clone 397009-8') stored in both traditional and cold storages. After spectroscopy measurements, these variables were measured using reference methods. Then, Partial Least Square (PLS) models were developed. To evaluate developed models, Root Mean Square Error of calibration and cross validation (RMSEC and RMSECV), as well as coefficient of determination for calibration and cross validation (R-C(2) and R-CV(2)), and Residual Predictive Deviation (RPD) were used. The best prediction belonged to reducing sugar with statistical values of R-C(2) = 0.99, R-CV(2) = 0.98, RMSEC = 0.029, RMSECV = 0.037, and RPD = 7.57 in 'Clone' genotype stored under cold storage. The weakest prediction was related to moisture content with statistical values of R-C(2) = 0.93, R-CV(2) = 0.92, RMSEC = 0.268, RMSECV = 0.279, and RPD = 6.45 in stored 'Clone' genotypes under cold storage. Results of the study showed that, Vis/NIR spectroscopy as a non-destructive, fast, and reliable technique can be used for prediction of inner compositions of stored potatoes.