Characterization of gelatin hydrogels derived from different animal sources

•Gelatin hydrogels are widely used in the regenerative medicine field.•Collagen animal source/treatment to obtain gelatin influence hydrogel properties.•Non-cytotoxic gelatin hydrogels obtained from porcine, bovine and fish source.•Gelatin hydrogels from various animal sources show different swelling properties.•Gelatin hydrogels from various animal sources show different mechanical properties.