This research evaluated the feasibility of using Fourier-transform near-infrared (FT-NIR) spectroscopy to quantify the soluble-solids content (SSC) and the available acidity (VA) in intact apples. Partial least-squares calibration models, obtained from several preprocessing techniques (smoothing, derivative, etc.) in several wave-number ranges were compared. The best models were obtained with the high coefficient determination (r²) 0.940 for the SSC and a moderate r² of 0.801 for the VA, root-mean-square errors of prediction of 0.272% and 0.053%, and root-mean-square errors of calibration of 0.261% and 0.046%, respectively. The results indicate that the FT-NIR spectroscopy yields good predictions of the SSC and also showed the feasibility of using it to predict the VA of apples.
© 2005 Optical Society of America
(060.0060) Fiber optics and optical communications : Fiber optics and optical communications
(120.0120) Instrumentation, measurement, and metrology : Instrumentation, measurement, and metrology
(300.6300) Spectroscopy : Spectroscopy, Fourier transforms
Yibin Ying, Yande Liu, and Yang Tao, "Nondestructive quantification of the soluble-solids content and the available acidity of apples by Fourier-transform near-infrared spectroscopy," Appl. Opt. 44, 5224-5229 (2005)