The Use of Partial Least Square Regression and Spectral Data in UV-Visible Region for Quantification of Adulteration in Indonesian Palm Civet Coffee

Table 2

Calibration and validation results for determination of luwak content in luwak-arabica blend using original and preprocessing spectra in the range 200–450 nm.

Type of spectra			RMSEC	RMSECV	Bias
Original	7	0.97	0.029	0.062	−0.003	2.92
Moving average smoothing with 5 segments	7	0.97	0.029	0.042	−0.002	4.31
Savitzky-Golay smoothing with window width of 13 points and polynomial order 2	7	0.98	0.028	0.039	−0.002	4.64
Median filter smoothing with 3 segments	7	0.98	0.027	0.050	−0.003	3.62
MSC	7	0.98	0.026	0.055	−0.001	3.29
SNV	7	0.98	0.025	0.054	−0.001	3.35
Baseline offset	7	0.98	0.027	0.060	−0.002	3.02
Mean centering	7	0.97	0.029	0.062	−0.003	2.92