Pasta is a commonly consumed food products all over the world. Principally, it is made by durum wheat (Triticum durum Desf.), but the high content on gluten determined to be replaced by other cereal flour. One of this is rice flour (Oryza sativa L.), which can be used solely or in combination with durum wheat flour for obtaining pasta. The goal of the study was to discriminate between various types of pasta by a simple, rapid and non-destructive combined technique, named attenuated total reflectance – Fourier-transform infrared spectroscopy coupled with principal component analysis (ATR-FTIR-PCA). Pasta products were obtained by classical recipes using durum wheat or rice flour, egg yolk and water. The dried products were finely ground and subjected to ATR-FTIR using a Bruker Vertex 70 FTIR equipment, with a spectral range of 4000-400 cm-1 and a resolution of 4 cm-1. The wavelengths and intensities corresponding of the characteristic ATR-FTIR bands for polysaccharides and proteins were used as input variables for PCA multivariate discriminant analysis. The wheat and rice pasta were well discriminated especially by means of FTIR intensities of C-O-H deformation of the starch glucose ring and ring vibrations overlapped by stretching vibrations of C-OH side groups and the C-O-C glycoside bond vibration (at 1644-1648 cm-1 and 996-1003 cm-1, respectively). Moreover, the unprocessed and processed (boiled and dried) samples were clearly discriminated by PCA. On the other hand, better classifications were obtained for pasta with egg yolk, which were discriminated from the control samples by the FTIR intensities of the above-mentioned bands that also includes C=O stretching from lipids and amide I and II bands at 1733-1748 cm-1 for νC=O and 1538-1541 cm-1 for νamide-II. In conclusion, the ATR-FTIR-PCA coupled technique allows discriminating pasta products and can be a useful technique to evaluate the quality of such type of food products.
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