When heated, proteinmolecule internal hydrogen bond broke,
which resulted to protein molecule expanding further. The
expanding process needed to absord quantities of heat
enthalpy; on the other side, protein agglutination and dewatering
reaction needed to release heat, producing exothermic
enthalpy. The sum of heat enthalpy and exothermic enthalpy
was relative enthalpy change. Denaturation temperature was
phase change peak value temperature. Peak area that DSC
curve formedwas the heat that protein denaturation absorbed.
Consequently estimating protein well-organized structure
denatured could investigate protein enthalpy change by DSC.
DSC results of three groups EWP were in Table 3. Protein in
three groups denaturation temperature ranged from 53 to
71 C, similar to fresh egg (65–70 C). Sulfydryl groups had a
great change in three groups, but DSC results had no significant
change. The result was in accord with the viewpoint of
Chuan-He Tang [24].The thermal denaturation of these proteins
was unrelated to their free SH contents [24]. Protein
properties had no significant changes, but relative enthalpy
change of spray drying optimized EWP was 1.06 J/g, which
was higher than the others. It illustrated that the optimized
EWP quality of spray drying was better.