Efecto de la temperatura y el número de frituras sobre el perfil de ácidos grasos de diferentes aceites comestibles

Abstract

Nowadays, frying is a common method to prepare foods such as French fries, snacks, among others; where the use of vegetable oils is indispensable, since they act as a means of heat transfer to the food at temperatures between 150°C and 200°C, in which the different factors of this process, added to the characteristics of the oils themselves can cause transformations of the lipids that make them up, giving rise to toxic compounds, typical of mechanisms such as oxidation and hydrolysis, which can negatively affect the health of the consumer. Because of this, it was proposed to evaluate the physicochemical characteristics, the effect of frying temperature on acidity, and the fatty acid profile at different temperatures and number of fryings of three edible oils of vegetable origin: Soybean (Glycine max), Chia (Salvia hispanica) and Sesame (Sesamum indicum L; for which 21 oil samples were obtained: 18 samples from 3 frying processes of potato (free potato variety) (stick form), at temperatures of 150 and 180°C; and 3 samples of the crude oils. These samples were analyzed for their physicochemical characteristics before and after the frying processes, resulting in the best treatment in terms of the lowest refractive index and peroxide value for the soybean oil at 180°C, with averages of 1.47053 and 2.54667, respectively. Similarly, the acidity changes presented by the oils at frying temperature conditions were determined, obtaining the best treatment for soybean oil at 150°C, with an acid index value of 0.11. Finally, the determination of the fatty acid profile of each oil after the treatments of # of frying and frying temperatures, gave the best treatment, in terms of a higher % of polyunsaturated fatty acids for the Chia oil with an average value of 50%, demonstrating also that the factors # of frying and temperatures affect the acid profile of the oils for the conditions of this study.