Study on the influence of the peel on predicting soluble solids content of navel oranges using visible and near infrared spectroscopy

摘要

Visible and near infrared (Vis/NIR) spectroscopy was applied to determine the soluble solids content (SSC) of navel oranges. The influence of the peel on absorption spectra and performances of calibration models developed with different wavelength regions was investigated. In addition, the calibration performances were compared. Spectra of 88 oranges with peel and peeled were collected using a commercial spectrometer. Partial least squares (PLS) regression was used to develop calibration models. Results showed that for intact oranges, calibration model using the visible and shortwave near infrared (Vis-SWNIR) region (520-1100 nm) performed similar to that using the NIR region (1101-2200 nm), and the Vis-NIR (520-2200 nm) did not improve the calibration models. With respect to the influence of the peel, in the Vis-SWNIR and Vis-NIR regions, the models using peeled samples performed slightly better, but not significantly. In the NIR region (1101-2200 nm), better results were obtained with models using intact samples. It was concluded that the peel of navel orange did not cause significant influence on the SSC determination using Vis/NIR spectroscopy.