Two dilute protein solutions were used as model fluids to test a mathematical model for the initial chemical reaction fouling rate of a heat transfer surface. Experimental results showed that at a given wall temperature, a maximum initial fouling rate existed over a range of velocities. This maximum rate and the fluid velocity at which it occurred both increased as the wall temperature increased. These observations were in accord with the model. Optimum model predictions yielded kinetic parameters, viz. reaction orders and activation energies, consistent with literature values, and the average absolute percent deviation between experimental results and optimum model predictions were 24.5 % for whey protein fouling and 23.3 % for lysozyme fouling.