Determination of the Degree of Degradation of Frying Rapeseed Oil Using Fourier-Transform Infrared Spectroscopy Combined with Partial Least-Squares Regression

Table 2

PLS analysis results for predicting the AV and TPC values of frying oil samples.

				SEC	SECV		SEP	Bias	RPD
AV	Raw spectra	5	0.99	0.20	0.22	0.99	0.22	0.03	9.2
	First derivative spectra	5	0.99	0.15	0.17	0.99	0.16	0.03	13.0
	Second derivative spectra	6	0.99	0.14	0.16	0.99	0.16	0.03	12.7
TPC	Raw spectra	6	0.98	1.13	1.26	0.98	1.13	0.00	7.1
	First derivative spectra	6	0.98	1.04	1.16	0.98	1.10	−0.09	7.3
	Second derivative spectra	6	0.98	1.05	1.17	0.98	1.10	−0.01	7.3

: number of factors; : coefficient of determination; SEC: standard error of calibration; SECV: standard error of cross validation; SEP: standard error of prediction; bias: average of differences between reference value and NIR value; RPD: ratio of standard deviation of reference data in the validation set to SEP.