Hydrolyzed glucomannan as an encapsulant for various iron concentrations using spray drying method

Abstract

Among the encapsulation methods, spray-drying is one of the simplest methods to protect iron from oxidation. Hydrolyzed glucomannan (HGM) has shown to have a potential as iron encapsulant in spray drying process due to its ability to form a barrier between the mineral and its surroundings. This work aimed to evaluate the effects of iron concentration (i.e., 20-50 ppm) on the spray dried powder properties using HGM as an encapsulant. The spray drying was conducted using Mini Spray Dryer B-290 Buchi. Feed temperature and aspirator were set at 100oC and 90% aspirator, with 1 mL.min-1 of flow rate. Increasing iron did not affect on encapsulation efficiency (98.66-99.4%) but allowed to push loading capacity from 30 to 61.5%. Lower iron concentration tended to result in more uniform particle size of the powders. Iron concentration insignificantly modified crystallinity and functional groups of the powder. Meanwhile, difference in thermal profile of spray-dry powders was observed due to iron concentration.