Study of the thermal stability of vegetable oils consumable in different environments

It has been studied the thermooxidative performance of three olive oils und er an oxygen, air and nitrogen atmosphere, using the Thermal Analysis techn iques, in order to make a comparative study in each case. Therefore, the da ta obtained of the TG-TGD curves, corresponding to the temperature at the b eginning of the degradation, at the 10% and 50% of the degradation, the fin al temperature, the maximum speed of degradation and the temperature corres ponding to that maximum, have been used. From the ATD curves, some qualitat ive data corresponding to the thermal effects (exo or endo), produced in th e thermal degradation of the oils and the respective temperatures have been obtained. With the thermogravimetrical data, a kinetic study of the oils thermodegrad ation reaction in every environment has been performed, and it has been cal culated the activation energy and the reaction order. The results obtained show the negative influence of the oxidising atmosphere on the thermal stab ility of the oils. On the other hand, this work may characterise the consum able vegetable oils, based not only on the characteristics of the thermogra vimetrical curves, but on the kinetic data deduced.