The effect of fat replacement by inulin on the physicochemical properties and microstructure of acid casein processed cheese analogues with added whey protein polymers

The objective of this study was to examine the effect of inulin as a fat replacer on selected physicochemical properties and microstructure of acid casein processed cheese analogues with added whey protein polymers. Meltability generally decreased, whereas textural properties such as hardness, adhesiveness, viscosity and density increased with increasing protein concentrations. In general, partial replacement of milk fat with inulin increased meltability, density, cohesiveness and viscosity (the latter only for 1% inulin), but it decreased sample hardness and adhesiveness. At the first stage of heating, the values of storage and loss moduli decreased with an increase in temperature, but increased at >41 °C in cheese analogues, in particular in products with lower milk fat levels and higher inulin content. All of the tested samples exhibited good melting properties. The addition of inulin to cheese samples did not influence their water activity, but altered their color. Confocal microscopy revealed that the highest hardness values could be attributed to more intense distribution of fat droplets in the sample with the highest fat content. Our results suggest that milk fat in processed cheese analogues can be partially replaced with inulin to improve the functional properties of the final product.