Garlic is widely used in cooking all over the world. Researchers at Queens University Belfast have verified whether NIR (near infrared) and FTIR (Fourier transform infrared) spectroscopy with chemometric analysis can detect garlic mixed with possible adulterants. Authentic and adulterated garlic (with talc, maltodextrin, corn starch, cornflour, peanut butter powder, sodium caseinate, potato starch, rice flour, cassava and white maize meal) samples were prepared at 20–90% levels, and NIR and FTIR spectra of the samples obtained. Principal component analysis (PCA) models were created to establish if there was separation of garlic from the adulterants.Orthogonal partial least squares – discriminant analysis (OPLS-DA) models were then developed to be able to detect and classify the levels of adulteration correctly using both NIR and FTIR.
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