Maestría en Química
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Item 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 AlexanderNowadays, 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.Item Determinación de la incidencia de la composición lipídica y bromatológica de la carne de res y cerdo comercializada en la provincia de Tungurahua(Universidad Técnica de Ambato. Facultad de Ingeniería en Sistemas, Electrónica e Industrial. Maestría en Química, 2022) Delgado Ramos, Andrea Verónica; Pérez Aldás, Lander VinicioMeat is a product in high demand in the Ecuadorian market, providing important nutrients in the human diet, such as protein, fat, vitamins, and minerals. However, despite the benefits it provides, some research has limited its consumption due to its high fat content and because it is considered a precursor of cardiovascular diseases and obesity. The objective of this research was to determine the incidence of the bromatological, and lipid composition of beef and pork marketed in the Province of Tungurahua. On analyzing the beef, 74.96 ± 5.97% moisture; 4.03 ± 0.97% ash; 0.99 aw; 6.24 ± 0.45 pH; and 10.70 ± 6.44% total fat were determined. Similarly, the analysis of the pork meat showed a moisture content of 69.50 ± 7.50%; 3.89 ± 1.17% ash; 0.99 in aw; 6.36 ± 0.26 in pH; and 33.15 ± 5.29%. As for the lipid profile, in beef, palmitic acid (37.44%); stearic acid (11.37%); oleic acid (38.95%); palmitoleic acid (2.62%); linoleic acid (7.11%); and linolenic acid (3.57%) were identified. In pork, palmitic acid (32.51%); stearic acid (10.02%); oleic acid (46.60%); palmitoleic acid (2.62%); linoleic acid (8.13%) and linolenic acid (0.64%) were found. Finally, the nutritional quality indexes obtained were saturation index (0.219 for beef and 0.202 for pork) and the atherogenicity index (0.729 for beef and 0.622 for pork). Therefore, the meats analyzed had an acceptable water composition, they are DFD meats, with high ash and lipid content, although they have a high content of FAs, they also report an important composition of FAp.Item Evaluación de la estabilidad oxidativa del aceite de chía (salvia hispanica l.) Obtenido por prensado a diferentes concentraciones de a-tocoferol como antioxidante(Universidad Técnica de Ambato. Facultad de Ingeniería en Sistemas, Electrónica e Industrial. Maestría en Química, 2021) Guayta Guaita, Irma Janeth; Briceño Carrasquel, Jorge AlexanderChia oil has a high content of polyunsaturated fatty acids, including linoleic acid (omega 6) and linolenic acid (omega 3); a characteristic highly valued for the prevention of cardiovascular diseases; the presence of these fatty acids causes a high chemical reactivity, so it is prone to oxidative transformations and isomerization; oxidative rancidity is one of the most important reactions of fatty acids, resulting in the loss of its nutritional value and shelf life of the oil. For this purpose, it was proposed to evaluate the oxidative stability of chia oil obtained by cold pressing at different concentrations of αtocopherol; to determine the oxidative stability of chia oil, 5 samples were prepared, TC 0% of Vitamin E and the T1, T2, T3, T4 with 0,025 %, 0,05%, 0,075 % and 0,10% of antioxidant respectively; demonstrating in the present study that T2 with 0,05% antioxidant is the best treatment to prolong the shelf life of chia oil, obtaining an estimated 264,395 days for its conservation and commercialization; Subsequently, the oil was stored at room temperature (15°C) for 15 months, after which time the fatty acids of the oil were quantified with 0,05% of alpha-tocopherol, obtaining as a result (17,71±0,07) % of linoleic acid and (65,03±0,19) % of linolenic acid and finally the physical-chemical tests were carried out, such as the percentage of humidity with (0,176±0,004) %, pH with (3,883±0,015) %, acidity indexes with (0,465±0,005) % and peroxide with (5,543±0,004) %; thus acquiring a product of excellent quality and suitable for human consumption.