Abstract:

The key reaction conditions (time, temperature and initial pH) for the complexation of FeCl3 with
isomaltooligosaccharide were optimized with respect to iron content of the final product by response surface methodology
using a central composite design. The formation and evolution of isomaltooligosaccharide-iron complex were elucidated by
measuring the pH, particle size, iron content, zeta potential, polydispersity index and conductivity of reaction products and
physicochemical properties of the final complex were characterized. Results showed that when the reaction proceeded for
2.7 h at 88 ℃ with an initial pH of 12.1, the obtained product contained up to 37.14% iron. The predicted optimal conditions
were demonstrated to be reliable. The resulting product had excellent physicochemical properties and therefore could be
expected to be developed into new iron supplements.

Key words: isomaltooligosaccharide-iron complex, preparation, process optimization, process monitoring, physicochemical properties