EVALUATION OF THE DENATURATION KINETICS OF 2 DIFFERENTLY PREPARED PROTEIN-CONCENTRATES FROM BOVINE BLOOD-PLASMA

Significant damage to the blood plasma protein matrix-measured by diff erential thermal analysis-starts at a temperature of 50 degrees C. The denaturation of the plasma protein can be described by dividing the p roteins into three fractions (I-III) which differ in their reaction ki netics behaviors. Two ways of producing protein concentrates have been investigated. Plasma concentrate A prepared by ultrafiltration genera lly shows a more sensitive behavior regarding temperature than does pl asma concentrate B prepared by evaporation. Temperature shifts of up t o 5 K and a decrease of the velocity constant of up to 2 decimal power s have been measured. It can be assumed that aggregation reactions dom inate the upfolding reaction with increasing ionic strength of the sol vent. The sharp bend (i.e. discontinuity of kinetics parameters) in th e Arrhenius display of the third fraction detected in plasma concentra te A does not occur in plasma concentrate B.