Enthalpy relaxation of gelatin in the glassy state

The enthalpy relaxation during the ageing of gelatin in the glassy state was studied for partially crystalline or amorphous materials at different water contents and ageing temperatures. The extent and rate of this relaxation associated with physical ageing were found to increase when the shifted temperature parameter (Ta − Tg) increased. This parameter was able to account for the effects of structure and water content (through Tg) and ageing temperature (Ta).