Rancidity Estimation of Perilla Seed Oil by Using Near-Infrared Spectroscopy and Multivariate Analysis Techniques

Table 2

Locations of function groups and corresponding vibration modes in the near-infrared region.

Wavelength (nm)	Vibration mode	Structure
900	C–H str. third overtone	CH3
1195	C–H str. second overtone	CH3
1215	C–H str. second overtone	CH3
1395	2C–H str. + 2C–H def.	CH3
1410	O–H str. first overtone	ROH