The present study had the purpose of evaluating the profile of fatty acids and the total alteration of cottonseed, sunflower and palm oils brought about during discontinued frying processes of cassava frozen chips. An increase in the percentage of saturated fatty acids and a decrease in polyunsaturated fatty acids was observed, regardless of the type of oil used. With regard to the oil's global alteration, the results showed that palm oil, the most saturated one, underwent less alteration. However, none of the oils presented total polar compound values above the limits prescribed.

O presente estudo teve como objetivo determinar a medida da estabilidade oxidativa e a alteração total dos óleos de algodão, girassol e palma durante a fritura descontínua de mandioca palito congelada. As frituras foram conduzidas em uma fritadeira elétrica doméstica, onde o óleo foi aquecido, à temperatura de 180°C, por 25 h, com reposição de óleo fresco. Para a análise da estabilidade oxidativa das amostras de óleos, obtidas durante as frituras, foram realizadas a medida do período de indução (horas) e determinação de compostos polares totais (%). Os resultados mostraram uma diminuição do período de indução, independente do tipo de óleo. O óleo de palma refinado apresentou um maior período de indução quando comparado ao óleo de algodão e girassol, o que pode ser atribuído à diferença da composição em ácidos graxos. Todos os óleos em estudo apresentaram valores de compostos polares totais abaixo do limite de descarte para óleos de fritura, exigido pela legislação internacional (24-27%). Verificou-se também que, à medida que se formaram os compostos de degradação, diminuiu a estabilidade oxidativa dos óleos.

The present study aimed at determining the oxidative stability measurement and the total alteration of cotton, sunflower and palm oils during frozen cassava chips discontinued frying. The fryings were performed in a household electric frying pan, where the oil was heated up to 180°C temperature, for 25 h, with fresh oil replacement. For the oxidative stability analysis of the oil samples obtained during the fryings, were used the induction period (hours) and total polar compounds determinations (%). The results showed a decrease in the induction period, regardless of the oil type. The refined palm oil presented a higher induction period when compared to the cotton and sunflower oils, which can be attributed to the fatty acids composition difference. All of the oils studied showed total polar compounds values beneath the discard limit for frying oils ruled by the international legislation (24-27%). It was also noticed that, as the degradation compounds were formed, the oils oxidative stability decreased as a result.