The study evaluated the effect of stabilizer containing diluted (1:4 with water) citric and formic acid (95:5 parts) on temperature stability of total mixed ration (TMR) for beef cattle fattening. Three variants were tested: control without stabilizer, stabilizer at lower dose 2 l/t, and at higher dose 4 l/t. Continuous temperature monitoring for 72 hours demonstrated temperature-dependent stabilizing effect. At high temperatures (30 oC), application rate 4 l/t was highly effective with TMR temperature reduction of 1.0 oC compared to control, while 2 l/t reduced temperature by only 0.1 oC. Under barn conditions, the lower dose was optimal with temperature reduction of 0.54 oC. TMR showed inherent metabolic activity with temperature increases up to 1.09 oC above ambient temperature at 30 oC. For practical use, 2 l/t dose is recommended under standard barn conditions as economically efficient solution and 4 l/t during high summer temperatures.