Temperature gradient in any process of transformation of matter is parameter that can affect the efficiency of the equipment. Bearing in mind this antecedent, we have simulated temperature behaviour in a discontinuous distiller for obtaining of essential oil by steam distillation. The thermal analysis was accomplished taking into consideration the typical raw material from Amazon Region of Ecuador as Ocotea Quixos, which have different physical and thermal properties as shape and specific heat respectively. The temperature gradient is affected for raw material mash, due to that the mash behave as thermal insulator and vary temperature distribution inside of the distiller by depending thickness of the mash, which is directly proportional to the raw material mass. The thermal analysis was done by finite elements, where we varied mash thickness with the respective specific heat of the raw material aforementioned and found range of thickness where temperature distribution is uniform inside of the distiller. Thereby, we determined with the aid of engineering program the amount of optimal raw material to increase output of essential oil inasmuch as with uniform temperature distribution the rate of heat and mass transfer increase.