Authentication of porcine, bovine, and fish gelatins based on quantitative profile of amino acid and chemometric analysis

Gelatin is a biological macromolecule derived from the partial hydrolysis of collagen protein. This paper describes a sensitive and rapid method for the detection of gelatin sources based on the composition of amino acids. Hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry (HILIC-MS/MS) and chemometric tools such as principle component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) were used for the analysis and spectral classification, respectively. Twenty amino acids are identified and quantified with the limit-of-detection (LOD) of 0.03–2.62 μg/mL and limit-of-quantification (LOQ) of 0.10–7.93 μg/mL, a precision of 0.19–11.21% and 0.03–13.62% (%RSD) for intra and inter-day, respectively, and a total recovery of 85.1–107.6%. Porcine gelatin showed correlation with glycine, proline, hydroxyproline, tyrosine glutamine, and glutamic acid; Bovine gelatin was correlated with lysine, leucine, and isoleucine histidine, phenylalanine, and alanine, and fish gelatin showed correlation with methionine, threonine, serine arginine and cysteine in PCA analysis. Verification of the developed method was confirmed by using different commercial and laboratory prepared gelatin products containing gelatin and the samples were successfully categorized into their respective sources. •Quantification of amino acids without derivatization in gelatins using HILIC-MS/MS.•Gly, Pro, Hyp, Glu, Gln, and Tyr were dominant in porcine gelatin.•Phe, Lys, His, Leu and Ileu, and Ala were dominant in bovine gelatin.•Ser, Thr, Meth, Cys, and Arg were dominant in fish gelatin.•Multivariant analysis successfully classified porcine, bovine, and fish gelatins.