Gelatin, the low molecular weight collagen derivative from porcine skin was transformed into a stable permanent hydrogel by
γ-radiation. A series of samples with 3% gelatin solution in water were irradiated at doses of 12, 25, 50, 100, 150, 200 kGy
at room temperature in the absence of air with a dose rate of 2.2 kGy/h. At low dose gelatin hydrogels incorporating all the
available water were obtained. At higher doses above 50 kGy, the gelatin hydrogel samples show a curious shrinking phenomenon
due to the relatively high crosslinking density level achieved, so part of the available water is squeezed out from the gel
cage. The gelatin hydrogel samples were studied by mass fractionation analysis, by spectrophotometric and polarimetric analysis.
Further characterization was made by FT-IR spectroscopy and by thermal analysis (DSC, DTA and TGA) of the dried gelatin samples
after irradiation in comparison to a reference untreated sample.