Maestría en Química

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    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 Alexander
    Chia 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.
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    Incidencia del suelo para la bioacumulación de Cadmio en la almendra de cacao (Theobroma cacao L.) de dos variedades Fino de Aroma y CCN51 cultivadas en el cantón Santa Clara provincia de Pastaza
    (Universidad Técnica de Ambato. Facultad de Ingeniería en Sistemas, Electrónica e Industrial. Maestría en Química, 2021) Guevara Uvidia, Mario Germánico; Briceño Carrasquel, Jorge Alexander
    Ecuador ranks fourth in world cocoa production and currently a problem for farmers is the bioaccumulation of Cadmium in soil and in cocoa crops. The objective was to analyze the incidence of the soil for the bioaccumulation of cadmium in the cocoa beans of two varieties cultivated in one of the farms of the Santa Clara Canton, Pastaza province. An experimental investigation was applied where physicochemical tests were developed in soils and in cocoa beans, a comparative analysis where the results achieved were related to the official Mexican soil standards and the European Union (EU) regulation for cadmium in cocoa. The characterization results in the sampled soils presented a “loamy sand” texture, pH values classified as “moderately acidic”, organic matter content in the soil where the CCN51 variety is grown presented a “high class” organic carbon content while that the soil where the Fino de Aroma variety was cultivated was classified in the “middle class” category, the minerals in the soil were determined as “high class” and the cadmium level presented a concentration that classifies them with a “normal level”. For the results obtained in the cocoa beans of the two varieties sampled, the cadmium content presented concentrations lower than 0.80 mg / kg obtained by atomic absorption spectrophotometry with a graphite oven. Finally, it was concluded that the cadmium concentrations of the two cocoa varieties did not exceed the levels established by the European Union and, according to the statistical analyzes carried out, it was found that the cadmium concentration in the soils did not present any correlation with the cadmium concentration. in the sampled cocoa beans.