Review for "Influences of different carbohydrates as wall material on powder characteristics, encapsulation efficiency, stability and degradation kinetics of microencapsulated lutein by spray drying"

Carotenoids are a class of natural pigments found mainly in fruits and vegetables. Among them,β-carotene is regarded the most potent precursor of vitamin A. However, it is susceptible to oxidation upon exposure to oxygen, light, and heat, which can result in loss of colour, antioxidant activity, and vitamin activity. Thus, the objective of this work was to study the microencapsulation process ofβ-carotene by spray drying, using arabic gum as wall material, to protect it against adverse environmental conditions. This was carried out using the response surface methodology coupled to a central composite rotatable design, evaluating simultaneously the effect of drying air inlet temperature (110-200°C) and the wall material concentration (5-35%) on the drying yield, encapsulation efficiency, loading capacity, and antioxidant activity. In addition, morphology and particles size distribution were evaluated. Scanning electron microscopy images have shown that the particles were microcapsules with a smooth surface when produced at the higher drying temperatures tested, most of them having a diameter lower than 10μm. The conditions that enabled obtaining simultaneously arabic gum microparticles with higherβ-carotene content, higher encapsulation efficiency, and higher drying yield were a wall material concentration of 11.9% and a drying inlet temperature of 173°C. The systematic approach used for the study ofβ-carotene microencapsulation process by spray drying using arabic gum may be easily applied for other core and wall materials.

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INFLUENCE OF EMULSIFICATION METHODS AND SPRAY DRYING PARAMETERS ON THE MICROENCAPSULATION OF TURMERIC OLEORESIN

Emirates Journal of Food and Agriculture ◽

10.9755/ejfa.2019.v31.i7.1968 ◽

2019 ◽

pp. 491 ◽

Cited By ~ 2

Author(s):

S. FERREIRA ◽

C. R. MALACRIDA ◽

V. R. NICOLETTI

Keyword(s):

Spray Drying ◽

Air Temperature ◽

Encapsulation Efficiency ◽

Curcuma Longa ◽

Chemical Properties ◽

Wall Material ◽

Operational Conditions ◽

Hydrophobic Compounds ◽

Emulsion Formulation ◽

Drying Conditions

Turmeric (Curcuma longa L.) oleoresin possess valuable phenolic compounds that are susceptible to degradation, and microencapsulation is a powerful technique to increase its stability. Emulsification is a preponderant step in microencapsulation of hydrophobic compounds and physical-chemical properties of the parent emulsion affects effectiveness of spray-drying process and functional properties of the produced microcapsules. The present work aimed to evaluate the influence of emulsion formulation, emulsification methods, and spray-drying operational conditions on the encapsulation efficiency of turmeric oleoresin using maltodextrin/gelatin blends as wall material. The effects of different concentrations of maltodextrin (12 - 31.7 wt %) and gelatin (0.6 - 6 wt %), combined with three methods of emulsification - high shear homogenization with and without emulsifier addition, and sonication – were evaluated regarding emulsion droplet mean diameter and stability. Based on the results, an emulsion formulated with 26 g of maltodextrin and 0.6 g of gelatin per 100 g of emulsion was selected to study the influence of spray drying conditions - drying-air temperature (124 – 190 oC), atomization airflow (275 – 536 L h-1), and emulsion feeding flow (1.4 – 8.6 mL min-1) - on encapsulation efficiency, water content, and solubility of turmeric oleoresin microcapsules. Sonication resulted in higher emulsion stability and, although drying-air temperature did not affect significantly the microcapsule properties, the best set of spray drying conditions was drying-air at 160 ºC, atomization airflow of 420 L h-1, and emulsion feeding flow of 6 mL min-1. Combinations of higher atomization airflow and lower emulsion feeding flow resulted in lower values of curcumin encapsulation efficiency.

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