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Micropartículas de pulpa de tuna anaranjada opuntia ficus-indica con mucílago de nopal y su aplicación como colorante en alimentos
(Universidad de Chile, 2020)
-indica) podría ser un colorante natural para alimentos de naturaleza hidrosoluble, que podría aplicarse en una amplia variedad de productos. El empleo de la microencapsulación por secado por atomización de la pulpa de tuna anaranjada, con mucílago de nopal y...
The use of natural colorants has raised interest as substitutes for synthetic or artificial dyes, which are considered harmful to the consumers' health. Indicaxanthin from the pulp of orange cactus pear (Opuntia ficus-indica) could be a natural food colorant of a water-soluble nature, which could be applied in a wide range of products. The microencapsulation by spray drying of the orange cactus pear pulp, with nopal mucilage and maltodextrin as encapsulating agents, could ensure the stability of indicaxanthin, enhancing its storage and performance as a food coloring. In this study, the optimal conditions of encapsulation by spray drying of orange cactus pear pulp (P) were determined, using nopal mucilage (M), maltodextrin (MD), and a mucilage-maltodextrin blend (M+MD) as encapsulating agents, to determine the effect of the polymer on the microparticle's characteristics. Stability during storage and as a colorant in two products (yogurt and soft drink) were also determined. The dryer inlet air temperature (T) and the pulp/encapsulating agent ratio (P/AE) were the independent variables. Indicaxanthin encapsulation efficiency (EE) and process yield (R) were the dependent variables. During the encapsulation optimization, the three microparticle systems (P-MD, P-M, and P-M+MD) showed indicaxanthin encapsulation efficiencies higher than 70%, due to indicaxanthin-polymer interactions by electrostatic interactions and/or hydrogen bonds formation. The yield ranged from 40% – 62% for P-MD, from 4% – 11% for P-M, and 5% – 32% for P-M+MD. In general, the P/AE ratio had a greater influence than the temperature in the encapsulation process and the optimal conditions were air inlet temperature, T= 150 °C, and 3:1 P/AE ratio. Under these conditions, the encapsulation efficiency and yield were 100% and 51.2% (P-MD), 87% and 7% (P-M), and 93% and 11% (P-M+MD), respectively. All the microparticle systems showed low moisture (less than 7%) and water activity (less than 0.3), and a high solubility (over 90%), which would allow them to be stored and applied in aqueous food formulations. Microparticles were stored for 7 weeks at 5, 37, and 60 °C, showing greater indicaxanthin and color stability at low temperatures. At 60 °C, the P-MD system showed the highest indicaxanthin stability, with 89% retention, while at 5 and 37 °C, P-MD, and P-M+MD exhibited retention of over 95%. Regarding color, at 5 °C a ΔE* < 2 was obtained in the three systems; however, a perceptible color change occurred at 37 in P-M and P-M+MD as well as at 60 °C in the three systems. Therefore, microparticles should be stored at low temperatures to ensure the stability of color and indicaxanthin. The P-MD and P-M+MD systems were added as colorants to natural yogurt and a soft-drink and compared to commercial products. In the yogurt, both colorants showed similar indicaxanthin and color stability, with retention higher than 80% and a ΔE* < 1. In the soft-drink, the P-MD colorant was more stable with 12% indicaxanthin retention, while the P-M+MD retention was 7.4%, after 28 days in refrigerated storage. In both beverages, the color change was close to 6. The differences between the food matrices (composition, pH) would explain these obtained results. Microparticles of orange cactus pear pulp could be used as yellow colorants in the food industry as a substitute for synthetic dyes...
The use of natural colorants has raised interest as substitutes for synthetic or artificial dyes, which are considered harmful to the consumers' health. Indicaxanthin from the pulp of orange cactus pear (Opuntia ficus-indica) could be a natural food colorant of a water-soluble nature, which could be applied in a wide range of products. The microencapsulation by spray drying of the orange cactus pear pulp, with nopal mucilage and maltodextrin as encapsulating agents, could ensure the stability of indicaxanthin, enhancing its storage and performance as a food coloring. In this study, the optimal conditions of encapsulation by spray drying of orange cactus pear pulp (P) were determined, using nopal mucilage (M), maltodextrin (MD), and a mucilage-maltodextrin blend (M+MD) as encapsulating agents, to determine the effect of the polymer on the microparticle's characteristics. Stability during storage and as a colorant in two products (yogurt and soft drink) were also determined. The dryer inlet air temperature (T) and the pulp/encapsulating agent ratio (P/AE) were the independent variables. Indicaxanthin encapsulation efficiency (EE) and process yield (R) were the dependent variables. During the encapsulation optimization, the three microparticle systems (P-MD, P-M, and P-M+MD) showed indicaxanthin encapsulation efficiencies higher than 70%, due to indicaxanthin-polymer interactions by electrostatic interactions and/or hydrogen bonds formation. The yield ranged from 40% – 62% for P-MD, from 4% – 11% for P-M, and 5% – 32% for P-M+MD. In general, the P/AE ratio had a greater influence than the temperature in the encapsulation process and the optimal conditions were air inlet temperature, T= 150 °C, and 3:1 P/AE ratio. Under these conditions, the encapsulation efficiency and yield were 100% and 51.2% (P-MD), 87% and 7% (P-M), and 93% and 11% (P-M+MD), respectively. All the microparticle systems showed low moisture (less than 7%) and water activity (less than 0.3), and a high solubility (over 90%), which would allow them to be stored and applied in aqueous food formulations. Microparticles were stored for 7 weeks at 5, 37, and 60 °C, showing greater indicaxanthin and color stability at low temperatures. At 60 °C, the P-MD system showed the highest indicaxanthin stability, with 89% retention, while at 5 and 37 °C, P-MD, and P-M+MD exhibited retention of over 95%. Regarding color, at 5 °C a ΔE* < 2 was obtained in the three systems; however, a perceptible color change occurred at 37 in P-M and P-M+MD as well as at 60 °C in the three systems. Therefore, microparticles should be stored at low temperatures to ensure the stability of color and indicaxanthin. The P-MD and P-M+MD systems were added as colorants to natural yogurt and a soft-drink and compared to commercial products. In the yogurt, both colorants showed similar indicaxanthin and color stability, with retention higher than 80% and a ΔE* < 1. In the soft-drink, the P-MD colorant was more stable with 12% indicaxanthin retention, while the P-M+MD retention was 7.4%, after 28 days in refrigerated storage. In both beverages, the color change was close to 6. The differences between the food matrices (composition, pH) would explain these obtained results. Microparticles of orange cactus pear pulp could be used as yellow colorants in the food industry as a substitute for synthetic dyes...
Construcción de identidades laborales de académicos de universidades privadas del Consejo de Rectores en el actual contexto chileno, a partir de sus producciones narrativas
(Universidad de Chile, 2016-12)
Santiago de Chile, Diciembre año 2016
RESUMEN
El contexto universitario chileno ha estado marcado por una ideología liberal
regulada, matizada por una serie de políticas que apuntan a atenuar los efectos de la
segregación del sistema educacional...
participantes de esta investigación. Se trabajó con una muestra de tres académicos universitarios provenientes de distintas universidades privadas del consejo de rectores de Chile (CRUCH). Los resultados fueron presentados en dos niveles: El primer nivel...
participantes de esta investigación. Se trabajó con una muestra de tres académicos universitarios provenientes de distintas universidades privadas del consejo de rectores de Chile (CRUCH). Los resultados fueron presentados en dos niveles: El primer nivel...
La política en la ficción melodramática durante la transición chilena al democracia. El caso de las telenovelas Volver a Empezar y Sucupira
(Universidad de Chile, 2019-12)
Este estudio analiza de qué manera aparece en pantalla -en especifico en la ficción melodramática- la política en Chile durante el periodo de la transición chilena a la democracia. Se trata de una investigación que a través de una discusión teórica...
El subsidio al arriendo como instrumento de integración social funcional: evaluación de los cuatro primeros años de aplicación (2013-2016)
(Universidad de Chile, 2019)
dotación de equipamiento, a través del arriendo. Esto es compatible con la aspiración de integración urbana en una dimensión funcional, presente en la Política Nacional de Desarrollo Urbano vigente. El diseño del Programa supuso que el beneficio haría...
La huelga en el derecho chileno desde el plan laboral de 1979. Apuntes históricos desde su gestación a la actualidad
(Universidad de Chile, 2014)
1
UNIVERSIDAD DE CHILE
Facultad de Derecho
Departamento de
Ciencias del derecho
LA HUELGA EN EL DERECHO CHILENO DESDE EL PLAN LABORAL DE 1979:
APUNTES HISTÓRICOS DESDE SU GESTACIÓN A LA ACTUALIDAD...
Ester Feres, profesora de Derecho del Trabajo UCEN. A la Fundación SOL, por brindarnos una cantidad ostensible de riguroso y vigente material en este tópico. A los compañeros citados aquí con sus Tesis en la materia, que contribuyeron a hacer a...
Ester Feres, profesora de Derecho del Trabajo UCEN. A la Fundación SOL, por brindarnos una cantidad ostensible de riguroso y vigente material en este tópico. A los compañeros citados aquí con sus Tesis en la materia, que contribuyeron a hacer a...
Estrategias de cultivo e inducción in vitro de células de Aristotelia chilensis (Maqui) para la obtención de antocianinas
(Universidad de Chile, 2015)
Las antocianinas del maqui son una materia prima de gran interés para la industria alimenticia y nutracéutica, debido al valor agregado que le confieren sus distintas propiedades farmacológicas y a la condición de endemismo de la especie vegetal...
"Estudio de las consecuencias del acuerdo de interconexión entre Transbank y otras empresas adquirientes en el mercado de medios de pago electrónicos en Chile"
(Universidad de Chile, 2014)
tarjetas de crédito y débito, han registrado durante las recientes décadas un crecimiento exponencial sostenido a nivel mundial y local. En Chile, este mercado tiene a su principal actor en Transbank, una sociedad de apoyo al giro bancario en la que los...
Valoración S.A.C.I. Falabella : mediante método de flujo de caja descontado
(Universidad de Chile, 2014-04)
valoración de empresas, considera tres factores claves al momento de establecer el valor de un proyecto o empresa: oportunidades de inversión a partir de una estimación de flujos, su distribución a lo largo de un horizonte de tiempo acotado y el riesgo...
Cambios de la Sexualidad en Chile, Significaciones y Grupos Sociales: La Delgada Línea Entre las Diferencias y las Desigualdades Sexuales
(Universidad de Chile, 2016)
y las bases sobre las que se estructuraría la diferenciación social, destacando así conceptos como doxa, hábitus y violencia simbólica, poder, dispositivo y disciplina, moral y democracia sexual, entre otros. Adicionalmente se ha requerido de una...
Conociendo el tránsito de la universidad al mundo del trabajo de los estudiantes de primera generación universitaria en Ingeniería y Ciencias: el caso de la FCFM, oportunidades y desafíos
(Universidad de Chile, 2020)
estas se vio jerarquizada (Leyton et al., 2012), quedando las credenciales educativas de mayor prestigio reservadas solo para una elite (Espinoza, 2015). Por otra parte, los estudiantes no pertenecientes a esta elite que logran ingresar a instituciones...