Preparation of Anthocyanin from Hibiscus sabdariffa Microcapsules and Evaluation of Stability and Release

The objective of this work was to avoid oxidation change which caused by the direct exposure to heat and light of anthocyanin and effectively control the release and stability of anthocyanins.Using chitosan and sodium alginate as wall materials, anthocyanin from Hibiscus sabdariffa as core material, the process of preparing anthocyanin microcapsules by piecing method and its microencapsulated anthocyanin infrared spectrum, storage conditions and in vitro release performents were studied in the paper. The optimum conditions for the preparation of anthocyanin microcapsules were determined by single factor experiments and response surface method. The structure and composition of anthocyanin microcapsules were analyzed by infrared spectrometer. The stability of anthocyanin microcapsules under different temperature and illumination conditions was investigated. The artificial gastric and intestinal fluids were simulated in vitro to evaluate the release of anthocyanin microcapsules. The results showed that, the optimum process parameters for the preparation of anthocyanin microcapsules were sodium alginate concentration 2.0%, CaCl₂ concentration 2.0%, wall to core ratio 2:1 g/g, chitosan concentration 0.1%, the embedding rate of anthocyanin from Hibiscus sabdariffa was 99.2%±0.16%.The results of infrared spectrum showed that, the absorption peaks of anthocyanins before and after microcapsules changed.The microcapsule anthocyanins could be stably stored at 4 or 25℃, and exhibitied sustained release effect in vitro release experiments.