Direct Sugar Content Analysis for Whole Stalk Sugarcane Using a Portable near Infrared Instrument

Cane quality at the farm is important information for both farmers and millers when evaluating cane maturity and determining harvest schedules. We investigated the non-destructive measurement of the sugar content of cane stalks using a portable near infrared (NIR) instrument. A commercially available portable NIR instrument was modified for use in transmittance mode and employed to quantify Pol levels in cane stalks. Calibration models using a partial least squares regression analysis were developed for predicting Pol values from the juice and the cane sample spectra (600–1100 nm). Results of these calibrations, root mean square error of prediction for juice and cane samples, were 1.0% and 1.1% Pol, respectively. Based on the results of this study, the developed measurement method appears to be useful for monitoring cane quality and the planning of harvest schedules.