Kinetic and Thermodynamic Parameters for Heat Denaturation of Bovine Milk IgG, IgA and IgM

For heat denaturation of bovine milk immunoglobulins (IgG, IgA and IgM) in the temperature range 62 to 81°C, the D values were IgG > IgA > IgM at any temperature. The Z values were 6.29, 4.00 and 5.17°C for IgG, IgA and IgM, respectively. Heat denaturation of bovine milk immunoglobulins followed a reaction kinetics in the order of n= 1.5. The highest value for apparent energy of activation was observed for IgA, and the lowest for IgG. Bovine milk immunoglobulins could resist the HTST pasteurization treatment at 72°C for 15 sec without affecting their structure.