An evaluation of Fourier transforms infrared spectroscopy method for the classification and discrimination of bovine, porcine and fish gelatins

•ATR–FTIR could be used to determine if sample contains any type of gelatin.•ATR–FTIR could be used to differentiate gelatin samples considering sources.•ATR–FTIR is simpler and less expensive method when comparing with other methods.•ATR–FTIR could be used for rapid determination of gelatin source. The objective of this research was to develop a rapid spectroscopic technique as an alternative method for the differentiation and authentication of gelatin sources in food products by using attenuated total reflectance Fourier transform infrared (ATR–FTIR) spectra combined with chemometrics. Clear discrimination and classification of all the studied gelatin sources (bovine, porcine, and fish) were achieved by hierarchical cluster and principle component analysis (PCA). Amide-I (1700–1600cm−1) and Amide-II (1565–1520cm−1) spectral bands were used in a chemometric method. Moreover, ATR–FTIR spectral data successfully discriminated pure bovine gelatin from mixture of bovine and porcine gelatins, which is very important for the food industry. The method that we adopted could be beneficial for rapid, simple and economic determination of both gelatin presence and its origin from food products such as yogurt, ice cream, milk dessert or other gelatin containing products such as pharmaceuticals and cosmetics.