923 research outputs found
Coenzyme q10 microparticles formation with supercritical carbon dioxide
Coenzyme Q10 is a powerful antioxidant used on cardiovascular, neurodegenerative and cancer diseases. Its hydrophobic nature do limit its applications, because human body absorbs it with dfculty, that is why it was proposed to increase its bioavailability by diminishing the particle size using supercritical carbon dioxide. It was determined experimentally the phase behavior of the coenzyme in a supercritical system. The equilibrium data and a factorial 2k experimental design were utilized to find how the shape and size of the microparticles are affected by temperature, coQ10 concentration and nozzle diameter. Microparticles were characterized using infrared spectrometry and chromatography. For verify the fundamental chemical structure, the size and the shape of the microparticles was used scanning electronic microscopy. It was found a significant decrease in particle size and a modification of physical structure. The antioxidant power of coQ10 after micronization was measured, showing an increase of this property. Finally, in order to evaluate the bioavailability, the kinetic of solubility was determined in ethanol, having a substantial increase on solubilization speed of micronized coQ10 compared with the commercial one
Microencapsulación de aceite de semilla de uva mediante secado por aspersión utilizando proteína de suero lácteo y pectina de tejocote
The use of O/W emulsions with well-functioning wall materials, such as whey protein and pectin from different origins, allows stabilization and protection of bioactive ingredients. The HP-protein interaction allowed the formation of thicker physical barriers, with high MEE and adequate morphology, which can stabilize GSO against oxidation processes. The GSO’s MEE was influenced by the TS content and the type of pectin used. The emulsions with hawthorn pectin from accessions 55 and 100, with 40 % TS, had the highest viscosities in the whole shear rate range. The EWPC-HP100,3:1 treatment produced microcapsules with the highest MEE (71.29 %) and the smallest emulsion droplet diameter (d3,2 = 1.45 μm). Generally, a reduction in droplet size is associated with greater stability for possible use in food matrices. The morphology of the capsules was affected by the type of biopolymer and the concentration of the wall materials. Microcapsules with HP100 had spherical particles with smaller dents on the outer surface than those formulated with CPObjective was to microencapsulate grape seed oil (GSO). GSO by spray drying of emulsions stabilized with biopolymer complexes formed from whey protein concentrate (WPC) and hawthorn pectin (HP) from two different cultivars Grape seed oil (GSO) contains unsaturated fatty acids that make it susceptible to degradation, causing it to deteriorate. In this sense, microencapsulation in biopolymer matrices is a good alternative to protect it. Emulsions were developed with different wall material: GSO ratios (2:1 and 3:1) and percentage of total solids (30 and 40 %). The wall materials were WPC-citrus pectin and WPC-HP from two cultivars (HP55 and HP100, with an esterification degree of 70.3 and 61 %, respectively). The factors evaluated were viscosity, mean surface diameter (d3,2) and morphology of the emulsions, and d3,2, microencapsulation efficiency (MEE) and electron microscopy of the microcapsules. The d3,2 of the emulsions ranged from 1.45 to 2.54 μm, where EWPC-HP100,3:1 exhibited the smallest d3,2. These values were related to the type of pectin and were inversely proportional to the viscosity and solids content. The highest MEE was presented by MWPC-HP100,3:1 (71.29 %), which had the highest viscosity and the lowest d3,2 in the emulsion
Modelo de un sistema de insonorización para minimizar el impacto acústico en el Hospital San José – Callao
La contaminación sonora en las ciudades es un problema constante debido a la
presencia de ruido en el ambiente generado por la cogestión vehicular, la industria,
el comercio ambulatorio, entre otros. Actualmente se viene adoptando diversas
medidas para mitigar con la contaminación sonora.
La presente investigación se enfoca en avaluar los niveles de contaminación
acústica y elaborar un modelo de un sistema de insonorización para minimizar el
impacto acústico el en Hospital San José – Callao.
La evaluación consiste en recoger datos en 10 puntos de monitoreo en torno a dicho
nosocomio mediante el uso de un sonómetro calibrado que posteriormente fueron
analizados y procesados obteniendo que en todos los puntos se sobrepasa lo
establecido en la normativa nacional vigente.
Una vez demostrado que existe contaminación acústica en el Hospital San José y
un posterior análisis costo-beneficio se diseñó un modelo den un sistema de
insonorización acústica, el cual tiene un valor a la fecha de S/. 204,395.10,
reduciendo los niveles de ruido a niveles inferiores que establece la normativa
nacional vigente
Supercritical Extraction Process of Allspice Essential Oil
Se presentan los resultados del proceso de extracción de aceite de pimienta utilizando dióxido de carbono supercríticoAllspice essential oil was extracted with supercritical carbon dioxide (SC-CO2) in a static process at three different temperatures (308.15, 313.15 and 318.15 K), and four levels of pressure (100, 200, 300 and 360 bar). The amount of oil extracted was measured at intervals of 1, 2, 3, 4, 5 and 6h, the most extraction yield reached was of 68.47% at 318.15K, 360 bar and 6h of contact time. In this supercritical extraction process, the distribution coefficient (KD), the mean effective diffusion coefficient (Def), the energy of activation (Ea), the thermodynamic properties (ΔG0, ΔH0 and ΔS0) and the apparent solubility (S) expressed as mass fraction (w/w) were evaluated for the first time. At the equilibrium the experimental apparent solubility data were successfully correlated with the modified Chrastil equation
Stabilization of phenolic compounds from opuntia oligacantha först by microencapsulation with agave sap (aguamiel)
The aim of this research was to determine the stability of phenolic compounds from Opuntia oligacantha Forst (xoconostle) ¨ by microencapsulation with a blend of biopolymers (maltodextrin and gum arabic) and agave sap (aguamiel) as a thermoprotector. The particle size distribution, morphology, stability during storage at different temperatures and water activity of the microcapsules were determined. The results showed significant differences (P<0.05) among the microcapsules. Higher protection was found in the microcapsules containing aguamiel. The microcapsules had a spherical shape with an average diameter of 7.72 µm. It was observed that the microcapsules containing aguamiel had a minor change in colour independent of the drying temperature and preserved the phenolic compounds for more than 1467 days at a storage temperature of 25 °C. These results suggest the application of microencapsulation with phenolic compounds from xoconostle for food products. Keywords: biopolymers, xoconostle, stability, spray drying
Determination of the minimum integral entropy, water sorption and glass transition temperature to establishing critical storage conditions of beetroot juice microcapsules by spray drying
The aim of this work was to microencapsulate beetroot juice (BJ) (Beta vulgaris L.) by spray-drying using as protective colloid
gum Arabic. The adsorption isotherms of the microcapsules and the minimum integral entropy (∆S int)T were determined at 25,
35 and 40 ◦C. The glass transition temperature (Tg) was measured by differential scanning calorimetry and modeled by GordonTaylor
equation. The water contents-water activity (M-aW ) sets obtained from (∆S int)T , and critical water content (CWC) and
critical water activity (CWA) from the Tg were similar, being in the range of water content of 5.11-7.5 kg H2O/100 kg d.s. and in
the water activity range of 0.532-0.590. These critical storage conditions were considered as the best conditions for increase the
stability of the microcapsules, where the percentage of retention Betanin in the microcapsules was higher compared with other
storage conditions in the temperature and aw range studied.
Keywords: beetroot juice, microcapsules, minimum integral entropy, glass transition temperature, critical water content, critical
water activity
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