The temperature influence on the oxidation stability of biodiesel from ternary mixture of vegetable oil and animal fat (50% of soybean oil, 20% of beef tallow, and 30% of poultry fat) was evaluated at temperatures ranging from 110 to 130 °C applying the Arrhenius and Eyring equations. The kinetics and thermodynamics parameters determined, considering first-order reaction rate kinetics, were rate constant (k), varying from 0.5479 to 1.7110 h −1 , activation energy (E a ) of 72.01 kJ mol −1 , preexponential factor (A) of 3.84 × 10 9 h −1 , enthalpy of activation (ΔH ‡ ) of 68.75 kJ mol −1 , entropy of activation (ΔS ‡ ) of −72.05 J K −1 mol −1 , and Gibb's free energy of activation (ΔG ‡ ) average of 97.08 kJ mol −1 . Based on the activation complex theory (ACT), the thermodynamic activation parameters indicated a nonspontaneous, endergonic, and endothermic process: ΔG ‡ > 0, ΔH ‡ > 0, and ΔS ‡ < 0, with estimated storage time of 149.82 d at 25 °C.

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The results indicated that samples planted in these two regions differ in their mineral content; however, conventional and transgenic samples grown in the same region show no difference in mineral contents in the grain.