Performance of FT-NIR instrument for Brix value measurement of intact pear fruit

The performance of a Fourier Transform-Near Infrared (FT-NIR) Instrument for fruit quality evaluation was investigated using pear fruits. Partial Least Squares (PLS) regression was carried out describing relationships between the data sets of laboratory data and the FT-NIR spectra. Besides cross and test set validation, the established models were subjected to a further evaluation step by means of additional pear samples with unknown Brix value. Performance of different models was also assessed in terms of Standard Errors of Prediction (SEP) and correlation coefficients (r) of validation set of samples. It was found that the calibration equation using interactance spectral data obtained with the FT-NIR instrument had a SEP of 0.32 and correlation coefficient (r) equal to 0.87 for Brix value. Based on the results, it was concluded that FT-NIR instrument could be an accurate and fast method for non-destructive evaluation of pear Brix value.