Preparation and Stability Evaluation of Black Rice Anthocyanin Microcapsules

Abstract

The stability of black rice anthocyanin microcapsules at high temperature, light and pH, and their release in simulated gastroenteric fluid were studied by emulsification and gelation of black rice anthocyanin microcapsules with calcium alginate as wall material. The stability of black rice anthocyanin in microcapsules prepared under the process parameters of sodium alginate concentration of 15 g/L, water oil volume ratio of 1∶3, wall to core ratio M (C3G)∶M (NaAlg) of 2∶1, and solution pH of 4.5 was significantly higher than that of uncoated free black ones under different pH, temperature, and light conditions. The microencapsulated anthocyanin could be kept for 4 hours in simulated gastric fluid, and the wall material was slowly decomposed and released in simulated intestinal fluid. The microencapsulation technology based on emulsified gel can improve the stability of anthocyanins, and achieve their intestinal delivery and sustained release in vivo.

Keywords

• black rice anthocyanins
• microcapsules
• emulsification and gelation
• stability
• releasability