On the separation, thermal and shear induced modification, and study of the functional properties of the major whey protein fractions

This work shows new ways for the development of milk products with the introduction of membrane fractionation procedures for the major whey proteins α-La and β-Lg in pilot scale. The obtained fractions were characterized during thermal treatment, resulting in the description of their denaturation kinetics and gelling properties when compared to the native mixture. Sheared heat induced gels of the whey proteins, also known as microparticles, were studied using simultaneous heating and shearing in a Scraped Surface Heat Exchanger, as well as using sequential processing with heating in a tubular exchanger followed by high pressure homogenization. The influence of spray-drying on the properties of the microgels was investigated in laboratory devices and in pilot scale. The functional properties of the obtained microparticles were investigated in exemplary solutions and complex dairy products. Besides model systems like ice cream and yoghurt, where their functional properties were demonstrated, interesting applications could arise from utilization of microparticles from isolated whey protein in cheese products or other non-dairy foods.