14F-5 |
Carotenoids retention efficiency and microstructure of microcapsules obtained by spray drying of W/O/W multiple emulsion |
M. E. RODRÍGUEZ-HUEZO1, C. I. Beristain2, R. Pedroza-Islas3, A. L. Prado-Barragán4, and E. J. Vernon-Carter1. (1) IPH, Universidad Autonoma Metropolitana-Iztapalapa, San Rafael Atlixco # 186, Mexico City, 09340, Mexico, (2) Instituto de Ciencias Básicas, Universidad Veracruzana, Luis Castelazo S/N, Col. Industrial-Animas, Xalapa, Ver., 91000, Mexico, (3) Departamento de Ingenierías, Universidad Iberoamericana, Prol. Paseo de la Reforma # 880, Mexico City, 01210, Mexico, (4) Departamento de Biotecnología, Universidad Autónoma Metropolitana, San Rafael Atlixco # 186, Mexico City, 09340, Mexico Substitution of artificial colorants by natural colorants in existing commercial products is difficult due to the limited variety of hues obtainable with the sparse natural colorants permitted as additives in foods for human consumption. These color hues could be expanded if water and oil soluble natural colorants can be contained in a single system. Also it is desirable that such system can be rendered as a powder as this presentation is easier to handle, to transport and to store. The objective of this work was to formulate W/O/W multiple emulsions containing water (saponified Aztec marigold oleoresin) and oil (red chilli oleoresin) soluble carotenoids, to obtain microcapsules by spray drying, and to evaluate the effect of different concentrations of wall material on carotenoids retention efficiency and microcapsule microstructure. Wall material used was a blend of mesquite gum-milk whey protein in a 60:40 ratio, with wall material:inner emulsion ratios of 1:1, 1.5:1 and 2:1. Color encapsulation efficiency was determined by quantifying total carotenoids retained in microcapsules by spectrophotometry in relation to initial carotenoids added to formulation. Microstructure was detemined with scanning electron microscopy. Best carotenoids retention efficiency was achieved with wall material: inner emulsion ratio of 1.5:1 and was 84%. Surface carotenoids accounted for 34% of total carotenoids. Sem micrographs show a smooth, devoid of defects surface topology, and a hollow center inner structure. A feature of these microcapsules is the formation of a centered deep well-like orifice attributed to water diffusion upon drying. Upon rehydration of microcapsules W/O/W multiple emulsions are reformed, so that it is inferred that inner emulsion is embedded on wall material upon drying. It is possible to efficiently blend water and oil soluble natural colorants into microcapsules obtained from W/O/W multiple emulsions.
Session 14F, Product Development: General
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