Beef patties are consumed worldwide because of their convenience and sensory characteristics. However, this product is commonly produced with lower nutritional quality fats. The aim of this study was to optimize beef patties formulation by mixture design using three alternative fat sources of higher nutritional quality (olive pomace oil (x1), subcutaneous pork fat (x2) and canola oil (x3)). A simplex centroid plan was built with these components and ten points, without any process variables and a third-degree model. The patties' fat content was determined by the Bligh Dyer method as presented by BRUM et al. (2009). The evaluated parameters were cooking yield, moisture retention, shrinkage percentage, fatty acid value of cooked patties (AOCS Ca 5a-40,1990), absorbance at 232 and 270nm for conjugated dienes and secondary compounds (IUPAC II.D.23, 1979), color analysis L, a* and b* (using MiniScan HunterLab at 25°C) and food texture parameters (firmness, toughness, hardness, adhesiveness, springiness, cohesiveness, resilience and chewiness in a Stable Micro Systems TA.XT at 25°C). The mixture design was used to predict the variables' behavior (α = 0.05) as a function of fat proportions. Under the conditions set in this work, it was possible to predict the behavior of beef patties for adhesiveness (R² = 97%; y = - 1.16x1 - 1.29x2 - 4.77x3 - 14.37x1x2 + 4.56x1x3 + 8.40x2x3 + 43.55x1x2x3) and fatty acid value (R² = 95%; y = 0.86x1 + 0.96x2 + 0.78x3 - 0.39x1x2 + 4.71x1x3 + 2.04x2x3 + 6.70x1x2x3). The formulation containing 16.7% olive pomace oil, 66.6% pork fat and 16.7% canola oil showed the higher cooking yield (76.7% ± 0.8) and texture, color, physicochemical and fat content results comparable to commercial hamburgers (p > 0.05). The mixture design showed to be an useful tool for the study and development of an improved formulation of beef patties.