Verification of a non-destructive measurement method for -cryptoxanthin in mid-late ripening citrus cultivars using visible and near-infrared spectroscopy

Previously, we have found that the use of visible and near-infrared (VIS-NIR) spectroscopy is a useful non-destructive method for quantification of beta-cryptoxanthin in Satsuma mandarin as an alternative method to HPLC. In this study, we examined whether the use of VIS-NIR spectroscopy would permit the quantification of beta-cryptoxanthin in mid-late ripening citrus cultivars. Examination of the associations between VIS-NIR spectra data and beta-cryptoxanthin contents was performed using partial least squares regression (PLSR). We found that the absorption in the region of 600 nm is particularly important for estimating the beta-cryptoxanthin content, and that the wavelength regions related to sugar content also affect the assessment of beta-cryptoxanthin. From these results, it is suggested that the use of VIS-NIR spectroscopy could allow prediction of beta-cryptoxanthin content in mid-late ripening citrus cultivars.