Maestría en Química

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Efecto de la temperatura y el número de frituras sobre el perfil de ácidos grasos de diferentes aceites comestibles
(Universidad Técnica de Ambato. Facultad de Ingeniería en Sistemas, Electrónica e Industrial. Maestría en Química, 2022) Villacrés Pérez, Mario Danilo; Córdova Suárez, Manolo Alexander
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.
Evaluación de la cinética de adsorción de fluoruro de agua natural mediante un lecho fluidizado de hidroxiapatita de calcio
(Universidad Técnica de Ambato. Facultad de Ingeniería en Sistemas, Electrónica e Industrial. Maestría en Química, 2021) Tirado Poveda, Hugo Marcelo; Córdova Suárez, Manolo Alexander
EXECUTIVE SUMMARY A fluidized bed with calcium hydroxyapatite (Ca10(PO4)6(OH)2) has been designed to reduce the concentration of fluorides in the natural water of the Totoras sector where fluoride concentrations in natural water exceed on average 3 mg/L F-, through the principle of ion exchange, the kinetics of fluoride adsorption on the solid matrix of commercial PAH was determined following an experimental design 2 at k=3, where by means of the response optimization analysis, the best treatment conditions were identified with a result of 0,83 ± 0, 02 mg/L F- of adsorbate in solution, after three days of treatment with a PAH load of 70 percent or 63 kg at a constant water flow of 2 L/min, indicating a maximum removal efficiency of 75.77 perecent, for which this treatment was adjusted to the linear model of the Langmuir Isotherm to be able to scale up the process to higher flow rates, For this purpose, the linear parameters of the Langmuir model were obtained with values of qmax of 1.15 mg of adsorbate per kg of adsorbent for a binding factor K of 2,76 liters of solution per kilogram of adsorbent.
Extracción, caracterización e índice de estabilidad del aceite de ajonjolí (Sesamum indicum L.) a diferentes condiciones de inhibición oxidativa
(Universidad Técnica de Ambato. Facultad de Ingeniería en Sistemas, Electrónica e Industrial. Maestría en Química, 2022) Ruiz Mora, Fátima Elizabeth; Córdova Suárez, Manolo Alexander
Sesame (Sesamum indicum) (sesame) of the pedaliaceae family, has a high content of oleic acid (omega 9) and linoleic acid (omega 6), fatty acids considered essential, which are supplied by the diet and used as a substitute for olive oil. The present research evaluates the oxidative stability of sesame oil, using two antioxidants: one natural (alphatocopherol) and one synthetic butylated hydroxytoluene (BHT) at different concentrations: 0.01%, 0.03% and 0.05% for the first antioxidant and 0.01%, 0.02% for the BHT, proving that the best treatment using the alpha-tocopherol antioxidant was of concentration 0. 05% with a shelf life of 43.46 months and for the BHT at a concentration of 0.02% 38.13 months, also at an average temperature of 15 oC; After obtaining the best treatment, the physicochemical parameters were evaluated before and after 4 months, obtaining peroxide index values of 5.08±0.05 control, 11.7±0.025 control after 4 months, 4.59±0.015 with 0.05% alpha-tocopherol at 4 months and 4.57±0.03 with 0.02% BHT, demonstrating that the added antioxidants maintain the stability of the oil. The acidity, iodine, saponification and refraction indexes before and after the treatments are within the values established by the Ecuadorian Standard NTE INEN 8:2012. Finally, the fatty acid content was quantified, the main ones being Oleic Acid 33.37±0.01% and Linoleic Acid with 50.97±0.02%, obtaining a product suitable for human consumption.