The effects of addition of animal fats (beef and pork fat), vegetable oils (ground-nut and maize oils) at a 20% level and essential oils (ginger and basilica essential oils) at a 0.2% level on the quality and stability of beef patties were investigated. The inclusion of animal fats and vegetable oils in the formulations significantly (P < 0.05) decreased the moisture and the protein contents but increased the fat content of the beef patties. While the highest pH values were found in the beef patties formulated with beef and pork fats, the lowest water holding capacity and the highest cooking losses were observed with the patties containing vegetable oils. The storage time significantly affected thiobarbituric acid (TBA) values. Formulations containing maize oil and essential oils showed the best characteristics in relation to oxidative and microbial stability with the lowest values for TBA and the lowest microbial loads when compared with the other samples. (C) 2003 Elsevier Ltd. All rights reserved.