One of the most important properties of whey protein is ability to create gels. The pH, ion power of solution, temperature, time of heating, concentration of proteins influence on behaviour of proteins in hydrous solution. The aim of this study was to investigate the method of heating, concentration of sodium chloride and calcium chloride on rheological properties and chemical structure of whey proteins. There were two methods of heating the WPI solutions applied. Single heating was led in pH 7,0 in temperature 80°C by 30 min., meanwhile double heating was first in pH 8,0 and after cooling to room temperature, pH was established on level 7,0 then was heated in 80°C by 30 min. The rheological properties of obtained polymers and measured by the HPLC were defined. Hardness of gels was growing along to the concentration of metals ions. The highest growth of storage modulus was in the case of dispersions with the highest concentration of sodium chloride (120 mM) and calcium chloride (15 mM). The chromatographic fractionation showed, that the addition of salt influenced on higher polymerization of whey proteins.
whey protein, rheology, polymerization, High Performance Liquid Chromatography (HPLC)