Carrera Ingeniería Bioquímica

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    Microencapsulación del ácido Ascórbico mediante secado por aspersión con almidón y Maltodextrina
    (Universidad Técnica de Ambato. Facultad de Ciencia e Ingeniería en Alimentos. Carrera de Ingeniería Bioquímica, 2017-04) Tapia Poveda, María José; López Hernández, Orestes Darío
    The objective of this work was the microencapsulation of ascorbic acid by spray drying to provide protection against certain chemical and physical factors, thus avoiding its easy degradation. For this purpose a preliminary analysis was carried out to determine the most efficient polymer mixture; Preparing mixtures of the maltodextrin / soluble starch polymers and maltodextrin / rice starch using a ratio of 1: 1, with a 20% loading of the active ingredient. Choosing this last mixture as the most optimal for the microencapsulation process, because a high yield was obtained with a value of 83.41 ± 0.56%. Subsequently, a blend design was applied obtaining as a better ascorbic acid loading of 40%, while the most optimal ratio of soluble starch and maltodextrin was found to be 1: 2. The highest values were obtained in both yield and efficiency, 83.41 ± 0.56% and 93.51 ± 0.80%, respectively. The product was qualitatively analyzed by Differential Scanning Calorimetry (DSC) and X-ray Diffractometry (XRD), with a decrease in the melting peaks and the diffraction maxima. In addition, it was morphologically characterized by the Scanning Electron Microscopy (SEM) technique, observing spherical and irregular microparticles, results obtained at weeks 0 weeks of microencapsulation, whereas at 28 weeks of storage the microspheres were mostly shrunk and agglomerated, But without losing its sphericity. Finally, an average particle size of 8.12 ± 3.92 μm was obtained.
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    Validación del método para la determinación de vitamina C (ácido ascórbico) en alimentos por Cromatografía Líquida de Alta Eficacia (HPLC)en el laboratorio ECUACHEMLAB Cía. Ltda.
    (Universidad Técnica de Ambato. Facultad de Ciencia e Ingeniería en Alimentos. Carrera de Ingeniería Bioquímica, 2017-09) Aguirre Arias, Sofía Lizeth; Córdova Suárez, Manolo Alexander
    Validation of a method is an important requirement to ensure reliable and reproducible results from test laboratories. Validation was performed using the methodology described by AOAC 967.21, supplemented with the methodology (Ledezma - Gairaud, 2004), under ISO / IEC 17025. The developed method produces a linear response with a correlation coefficient r = 0.999 for each curve Calibration, LD equal to 0.0002 mg / ml and LC equal to 0.007 mg / ml. The working range comprises values from 0.007 mg / ml to 0.1448 mg / ml for the concentration of ascorbic acid ranging from 7.25 mg to 142.73 mg of vitamin C per 100 g of sample. The coefficient of variation was less than 2 percent for repeatability and reproducibility. The percentage recoverability was found in the range established for HPLC with a value equal to 99.32 percent. The limits of repeatability and reproducibility with values of 2.16 mg / 100 g and 2.61 mg / 100 g of ascorbic acid, respectively. The combined uncertainty of the method for all concentration levels employed with a value equal to +/- 0.95 and the expanded uncertainty with a value equal to +/- 1.91 expressed in units of mg of vitamin C per 100 g shows; It was used as an acceptance criterion that the value of the uncertainty is less than 30 percent of the low range resulting in the uncertainty found 26.31 percent, thus fulfilling the objective of validation.