Stability and Tg
The glass transition temperature and the molecular mobility are the principal predictors of stability of amorphous material.
Glasses and polymers are brittle below and soft above the the glass transition temperature (Tg), which also is manifested in a change in heat capacity (ΔCp) in this region. The chance in heat capacity and the glass transition temperature region can be determined by use of DSC.
Proteins as strong glass formers, which results in a small heat capacity chance at Tg. In fact the change in heat capacity is often so small that is often undetectable using standard calorimetry techniques.