Avaliação do efeito da temperatura, ciclos de aquecimento e adição de metais na estabilidade oxidativa de óleos vegetais

Abstract

Vegetable oils have a great economic importance due to their diverse applications, especially in the food industry. It is important to guarantee the quality of the product, to avoid deterioration, which causes changes in its odor, taste and appearance, in addition to the appearance of compound toxic to health. The beginning of deterioration occurs when the oil is exposed to several stages for its extraction, but its quality is mainly affected during its heating in frying processes. This heating, whether intermittent or continuous, causes great damage to the oil. In this sense, this work has emerge to determine the influence of temperature, heating cycles and the presence of metallic elements in the physicochemical properties of vegetable oils. Analyzes were carried out to determine the deterioration of vegetable oils, such as acidity index, iodine index and refractive index in samples that were heated in situations that simulate industrial application - industrial fryer at 250ºC in intermittent cycles; and home cooking - continuous heating at 180ºC. The results indicated that heating, whether intermittent or continuous, has an influence on the increase of degradation in vegetable oils and those metals have a catalytic effect on oxidation.