Crude red palm oil is a traditional cooking oil in many tropical countries especially in West Africa. Ghanaian researchers (in cooperation with Queens University Belfast) have developed a rapid, non-destructive method to detect Sudan dye adulteration of red palm oil using a portable NIR spectrometer with multivariate analysis. The multivariate model was determined using a total of 520 samples of red palm oil comprising; 40 authentic samples together with 480 adulterated samples containing Sudan dyes (I, II, III, IV of 120 samples each). Principal component analysis (PCA) was used to extract relevant spectral information, which gave visible cluster trends for authentic samples and adulterated ones. The optimised results by cross-validation revealed that MSC-PCA + SVM (Support Vector Machine) gave an identification rate above 95% for both calibration and prediction sets, and hence ould be used successfully to differentiate between authentic red palm oils and adulterated ones.
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