Employing the dynamic-mechanical thermal analysis (DMTA) method, an attempt was made to determine the effect of the replacement of fat by a mixture of preparations (Provico lV, starch thickener E1412, pea fibre ID90 and swine blood plasma Apropork) on the mechanical-rheological properties of finely-ground sausage fillings during thermal treatment. It was found that, at room temperature, the fat solid phase had a decisive influence on the development of the rheological properties of the control filling as well as systems with fat replaced by a mixture of preparations. Changes caused by the temperature increase within the confines of the continuous phase of meat fillings at the initial stage resulted in the liquefaction of fats and liberation of water dispergated in fats causing increased liquidity of the system. The comparison of the value of the rigidity modulus of the final product cooled down to room temperature with the filling which was not subjected to thermal treatment revealed a fivefold increase of its value. Together with the increase in the level of fat replacement by the mixture of preparations, there was a decrease of the product elastic properties and, consequently, an increase of its plasticity.