Abstract
In this work, maltodextrin-grafted-cinnamic acid (MD-g-CA) was synthesised and used as wall material to improve the stability of purple sweet potato anthocyanins (PSPa) via microencapsualtion. MD-g-CA was prepared through esterification in a two-step convenient synthesis procedure and characterised using infra-red (IR) spectroscopy. The IR data indicated the typical ester carbonyl stretching at around 1721 cm−1. Moreover, MD-g-CA could give about 40% inhibition of DPPH radical and present excellent UV-absorption, which were notably better than that of native MD. Maltodextrin (MD) and MD-g-CA were used to prepare PSPa microcapsules by spray drying. The stability of PSPa was evaluated by UV-Vis analysis. The microcapsules produced by MD-g-CA showed a spheres-like appearance with some cracks. Storage tests revealed that the degradation rate of PSPa embedded by MD-g-CA was much lower than that of free PSPa under the same condition. Thus, MD-g-CA could be used as an effective wall material to improve stability of anthocyanins.
Disclosure statement
The authors report no conflict of interest. The authors alone are responsible for the content and writing of this article.