Authentication of Nigella sativa Seed Oil in Binary and Ternary Mixtures with Corn Oil and Soybean Oil Using FTIR Spectroscopy Coupled with Partial Least Square

Table 3

PLS performances at some frequency regions for the determination of NSO in binary mixtures with CO.

Frequencies region (cm^−1)	Spectra	Calibration		Validation
		𝑅^2	RMSEC (% v/v)	𝑅^2	RMSEP (% v/v)
4000–650	Normal	0.9818	3.50	0.9542	3.06
	Derivative 1	0.9904	2.12	0.9975	1.32
	Derivative 2	0.9968	1.61	0.9975	1.15
2977–3028,; 1666–1739,; 740–1446	Normal	0.9929	2.23	0.9849	2.80
	Derivative 1	0.9933	1.85	0.9970	1.41
	Derivative 2*	0.9984	1.34	0.9987	0.66
1666–1739	Normal	0.9926	2.48	0.9929	1.83
	Derivative 1	0.9966	1.55	0.9950	1.88
	Derivative 2	0.9915	2.08	0.9978	1.21
740–1446	Normal	0.9983	1.11	0.9965	1.34
	Derivative 1	0.9983	1.19	0.9983	0.87
	Derivative 2	0.9921	2.20	0.9952	1.82

*The frequency region and FTIR spectral treatment selected for quantification were marked with italics.