Non-destructive assessment of quality traits in apples and pears usingnearinfraredspectroscopy and chemometrics

-The objective of this study was to evaluate the performance of a hand-held NIR spectrometer for non-destructive quality analysis of apples and pears pro-duced in the Brazilian Semi-arid region. NIR spectra were acquired with a portable spectrometer in the wavelength range of 750-1065 nm and reference analyses of dry matter content (DMC) and soluble solids content (SSC) were measured weekly during 10 weeks of storage at 0.5 & DEG;C. Spectra were pre-processed with standard nor-mal variate and used to develop DMC and SSC models using partial least squares re-gression with full cross-validation. The models were validated using data not includ-ed in the calibration. Satisfactory prediction results were obtained for SSC in apples (R2 = 0.58) and pears (R2 = 0.55), and for DMC in apples (R2 = 0.55) and pears (R2 = 0.65). All prediction models showed a relative root mean square error of prediction lower than 8%. These findings indicate that the NIR spectrometer is a promising tool to be used for a rapid and non-destructive determination of internal quality traits in apples and pears.