Effect of calcium content and flow regime on whey protein fouling and cleaning in a plate heat exchanger

Fouling and cleaning with a whey protein concentrate solution in a plate heat exchanger were investigatedwith a varying calcium concentration (from 70 to 87.5 mg L 1) and under a wide range of hydrodynamicconditions for a bulk fouling fluid temperature, ranging from 60 and 96 C.This work demonstrates that increasing the calcium concentration in whey protein concentrate contributesto the amount of fouling and affects the thermal conductivity of the deposit. It was also observedthat the fluid flow regime during fouling, impacts the deposit growth, modifies the structure of fouledlayers and has a significant consequence on cleaning behaviour.Finally, a dimensional analysis together with experimental measurements, allowed a relationship to beestablished enabling prediction of the amount of dry mass deposited locally as a function of the knowncalcium content, Reynolds number and bulk fluid temperatur

Effect of the calcium/protein molar ratio on β-lactoglobulin denaturation kinetics and fouling phenomena

Understanding the mechanism of whey protein fouling along a plate heat exchanger is a challengingissue in the dairy industry. The influence of the calcium/protein molar ratio on b-lactoglobulin (b-LG)denaturation and its consequence both on fouling mass along the plate heat exchanger and the structureof the fouling layer were studied. The experimental design was defined by varying the calcium/proteinmolar ratio from 2.3 to 22.9 and fixing the total concentration of calcium at 100 ppm. Results establishedthat both the b-LG denaturation rate constants and the distribution of fouling in the plate heat exchangerwere strongly impacted by the calcium/protein molar ratio. Structural analysis provided evidence thatthe fouling layer evolved from a thin and dense structure at low calcium/protein molar ratio towards athicker and more open structure at higher calcium/protein molar ratio