Pistachio is one of the most expensive nuts, and is prone to adulteration because of its high commodity value. The most common adulterants are green pea and peanuts with added colours. Turkish researchers have developed a non-targeted method using portable FT-IR (Fourier Transform infared) and UV–Visible spectrometers. Samples of pistachio granules were adulterated with green pea and peanut at concentrations from 5-40% w/w, and their spectra taken using a portable FT-IR spectrometer and a conventional UV–Vis spectrometer, which were analysed by Soft Independent Modeling of Class Analogy (SIMCA) to generate classification algorithms to authenticate pistachio. Partial Least Square Regression (PLSR) was used to predict the concentrations of adulterants, and both instruments gave excellent predictions of adulterant levels.
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