Effect of viscosity on iron encapsulation using alginate as a carrying agent in a controlled spray drying process

Abstract

The encapsulation method is a method that protects Fe from oxidation, increases bioavailability and reduces the unwanted taste, aroma, and distinctive colour of Fe. Alginate is used as an encapsulant because it can be regulated in viscosity. The drying process by spray drying is chosen to obtain the final product that has the appropriate quality standards. The purpose of this study was to determine the effect of alginate 50 mPas, 100 mPas, 150 mPas, 200 mPas, 250 mPas and 300 mPas viscosity on the characteristics of powder encapsulation. The results showed that the higher the viscosity, the darker the colour of the powder produced. Powder particle size increases with increasing viscosity; and the higher the viscosity, the higher the moisture content. The solubility of the alginate-Fe encapsulated powder was lower with increasing viscosity. The particle morphology shows a lot of indentation and unevenness, and the pore size is bigger at a viscosity of 150 mPas to 300 mPas. The alginate-Fe encapsulated powder of all viscosity variables showed the same functional groups but in different intensities. At the testing of Fe2+ levels, it turned out that Fe3+ had higher levels than Fe2+. The process of releasing Fe2+ at pH 1.2 was slower than pH 6.8. From the research results, alginate-Fe encapsulation powder with a viscosity of 100 mPas produced the highest performance in protecting Fe, thus, a good viscosity of the feed solution was recommended in the spray drying process.