Investigation of Butter Adulteration with Margarine Using 1H NMR and PCA

Abstract

In this work, the assessment of butter and margarine using 1H nuclear magnetic resonance (NMR) spectroscopy and principal component analysis (PCA) was achieved successfully. The first two PCs that account for more than 90% of the total variation in the spectral dataset were used in constructing the PCA score plot. 40 samples of butter from 8 brands and 35 margarine samples from 7 brands were studied. To imitate adulterated butter with margarine, a selected butter brand was mixed with different mass ratios of a selected margarine brand (5, 10, 20 and 30%). All samples in this study were dissolved in CDCl3 and analyzed in a similar manner. Again, successful detection of margarine adulterated butter was achieved. Quantitative determination of adulteration was not possible in the current study. In all PCA parts through this study, data corresponding to the chemical shift period (2.5–1.0 ppm) produced the best assessment results. Hence, this part from all spectra was used throughout this study.