Abstract: The contents of heavy metals, amino acids, nucleosides and fatty acids in donkey hide gelatin and deer skin gelatin were measured by inductively coupled plasma mass spectrometry (ICP-MS), automatic amino acid analyzer, ultra performance liquid chromatography (UPLC) and gas chromatography (GC), separately. Results showed that the contents of Pb (1.00 mg/kg) and Cu (0.80 mg/kg) were much higher than those of other heavy metals (< 0.1 mg/kg). The contents of total amino acids in the two gelatins were 85.66% and 90.02%, where the proportions of essential amino acids were 16.14% and 15.89%, respectively. Glutamic acid, glycine, alamine and proline were the dominant amino acids. Twelve nucleosides were detected in donkey hide gelatin with the dominance of xanthine (35.46 μg/g), while 9 nucleosides in deer skin gelatin, xanthine being the major one (70.44 μg/g). The major fatty acids found in both gelatins were palmitic acid, palmitoleic acid, oleic acid, and linoleic acid; saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) were more abundant in deer skin gelatin than in donkey hide gelatin. On the other hand, the contents of polyunsaturated fatty acids (PUFA), essential fatty acids (EFA) and n-6 unsaturated fatty acids were higher in donkey hide gelatin. The ratios of SFA/MUFA/PUFA in both gelatins were close to the healthy ratio.

Key words: donkey-hide gelatin, deer skin gelatin, chemical quality