INVESTIGATION OF THE RHEOLOGICAL CHARACTERISTICS OF PROCESSED CHEESE

doi: 10.25712/ASTU.2072-8921.2021.04.005

Abstract

Rheological measurements are very relevant in the food industry as a tool for the physical characterization of raw materials before processing, for intermediate products in the production process and for finished food products. The purpose of this study was to determine the effect of temperature and chemical composition on the rheological characteristics of processed cheese, as well as to measure the apparent viscosity of the product during cooling and during processing. A rotary viscometer was used to determine the apparent viscosity. The apparent viscosity of the processed cheese was determined at 50, 60, 70, 80 and 90 ºC until the products solidified when the product samples were still in the emulsion state. The dependences of the flow behavior index and the consistency coefficient on the moisture content of the processed cheese are obtained. The found values of the flow behavior index indicated the pseudoplastic nature of the processed cheese. The flow characteristics of the cheese samples were analyzed using a regression procedure to describe the effect of temperature and chemical composition on rheological parameters. An increase in the flow behavior index was observed with increasing moisture content and product temperature. The consistency factor and therefore the apparent viscosity increased with decreasing temperature and humidity. It is concluded that the apparent viscosity of processed cheese during processing is most influenced by water and proteins (continuous phase), while fat (dispersed phase) has no significant effect.