THERMAL-PROPERTIES OF COLLAGEN-WATER SYST EM .1. INCREMENTS OF HEAT-CAPACITY AT DENATURATION AND GLASS-TRANSITION

The absolute values of heat capacity of the collagen-water systems wit h different relative content of the components in both native and dena tured state were studied by the method of differential scanning calori metry in a wide temperature range (-40+/-140 degrees C) which includes the region of the denaturation phase transition as well as the region of the relaxation glass transition. From the experimental data the va lues of denaturation increment Delta C-pnd-0,42+/-0,04 J/(g.K) at the collagen content 10-50% and the values of glass transition increment D elta C-pg-0,54+/-0,12 J/(g.K) for moist denatured protein were calcula ted. Different processes influencing the increment values are analysed . The nonequilibrium character of the glass-like state of moist protei ns was clearly demonstrated in the study of glass transition.