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In this report, we study the electro-optics effect on cooking oil to obtain the relative dissociation energy as a new single proposed parameter of oil quality. The sample was canola oil which had been heated in 0.5 hours, 2 hours and 4 hours. The light source used in the experiment was a green pointer laser with a wave length of 532 nm. The sample was applied to a potential difference from 0 to 9 kV to obtain the electro-optics effect in form of the change of the polarization angle Dq as function of potential difference DV. The relative dissociation energy was obtained from the fitting data of the relative Lenard-Jones potential energy curves represented by change of polarization per unit change of potential difference, Dq/DV. The result shows that the relative dissociation energy is reduced as the oil quality decreased after heated. The relative dissociation energy provides simple physical understanding about electro-optics effect on cooking oils. The study of electro-optics polarization that represents relative Lenard-Jones potential energy is a new but somewhat intuitive, which can be further improved and emphasized for grouping, mapping, and determining various cooking oil quality and halal food due to the lard contamination.

In this paper we studied contribution of electro-optics effect for evaluation of canola oil quality using transmission and fluorescence polarization. The samples were two different quality of canola oils, i.e. edible canola and expired canola based on the date of expiration at the time of measurement. The physical variable of polarization angle was measured using a pair of polarizers from a 532 nm of green pointer laser. The electro-optics effect was produced by applying high DC voltage 0-9 kV on samples. The result shows that the change of polarization angle of expired oil is greater than the good one for both transmission and fluorescence. The increasing polarization angle is accompanied by increasing saturated FAs and decreasing polyunsaturated FAs simultaneously, in agreement with our previous reports.The fluorescence polarization is dependent on the polarizer’s angle of incoming light and has average angle greater than transmission light. The electro-optic fluorescence is twice as electro-optics transmission due to possibly coupling between pure scattering and fluorescence together, in which large size of TG molecules play an important role into the light scattering and fluorescence perpendicular to the incoming light.This fluorescence light method provides more accurate measurement that transmission light and seems powerful comparison to the other spectroscopy methods.

In this report we have succeeded to map various cooking oils using change of fluorescence polarization. Various cooking oils consisted of several vegetables oils and animal oils (chicken oil and lard) were used in the experiment, and some oils were measured in two different times. The change of polarization angle &tetha; was measured as the difference between linear polarized green pointer laser as incoming light and fluorescence light using a pair of polarizers. The direct measurement of fluorescence polarization gives a new unique result of critical polarizer’s angle φc that can group vegetable cooking oils into group 1 (at φc = 10o for VCO, olive, and soybean), group 2 (at φc = 20o for palm, corn and rice bran), group 3 (at φc = 30o for sunflower and canola), and also animals cooking oils into group 4 (at φc = 20o for chicken oil), and group 5 (at φc = 40o for lard). Mostly cooking oils can be distinguished using modified maps. The large difference φc and &tetha; of lard from vegetable oils provides an advantage to develop for testing halal oil due to lard contamination. The capability of this method has benefits, at least, as a complement and simple method in comparison to other expensive sophisticated instruments such as fluorescence spectroscopy or GCMS methods with their derivation’s instruments.