Fr. Vandevoort et al., THE DETERMINATION OF PEROXIDE VALUE BY FOURIER-TRANSFORM INFRARED-SPECTROSCOPY, Journal of the American Oil Chemists' Society, 71(9), 1994, pp. 921-926
A rapid method for the quantitative determination of peroxide value (P
V) of vegetable oils by Fourier transform infrared (FTIR) transmission
spectroscopy is described. Calibration standards were prepared by the
addition of t-butyl hydroperoxide to a series of vegetable oils, alon
g with random amounts of oleic acid and water. Additional standards we
re derived through the addition of mono- and diglyceride spectral cont
ributions, as well as zero PV spectra obtained from deuterated oils. A
partial least squares (PLS) calibration model for the prediction of P
V was developed based on the spectral range 3750-3150 cm(-1). Validati
on of the method was carried out by comparing the PV of a series of ve
getable oils predicted by the PLS model to the values obtained by the
American Oil Chemists' Society iodometric method. The reproducibility
of the FTIR method [coefficient of variation (CV) = 5%)] was found to
be better than that of the chemical method (CV 9%), although its accur
acy was limited by the reproducibility of the chemical method. The met
hod, as structured, makes use of a 1-mm CaF2 flow cell to allow rapid
sample handling by aspiration. The spectrometer was pre programmed in
Visual Basic to guide the operator in performing the analysis so that
no knowledge of FTIR spectroscopy is required to implement the method.
The method would be suitable for PV determinations in the edible oil
industry and takes an average of three minutes per sample.