Исследование реодинамики йогуртов, обогащенных селеном

The article substantiates the need for the development of functional formulations for dairy products enriched with selenium. The problem of formulation selection for functional fermented milk beverages with selenium is analyzed in terms of recoverability of their structural and mechanical properties. The rate of dynamic viscosity coefficient change with the change of shear rate γ was selected as a criterion for assessing the recoverability of the beverage structure. At the first stage the recoverability of the drink structure was studied and the choice of beverage with the best recoverability was made. The experimental technique is described. Seven functional beverages with different formulations were analyzed and P7 drink was selected. The main stage of the research was the rheological properties analysis of the beverage selected in a wider range of shear rates ( γ = 2 ÷ 1000 c -1) in order to obtain mathematical data for dynamic viscosity calculation. It was found that all the investigated dairy products had non-Newtonian properties of flow and belonged to the group of pseudoplastic liquids with thixotropic properties. Two groups of equations are presented to calculate the dynamic viscosity coefficient: for increasing and decreasing shear rate. The equations obtained are necessary to calculate hydraulic resistances when product flows in tubes and in batching equipment.