Preparation and evaluation of an encapsulated anthocyanin complex for enhancing the stability of anthocyanin

Anthocyanin is of great interest because of its many biological activities. However, its structure is extremely unstable, limiting its applications. In this study, we used polyethylene glycol (PEG) and chitosan as wall materials and purified mulberry marc (Morus alba L.) anthocyanin as the core materials to prepare a PEG- and chitosan-encapsulated anthocyanin complex. The best process, which was optimized with response surface methodology, used a 20:1 mass ratio of PEG4000 to chitosan and 1:3.8 ratio of core to wall materials. By regularly determining the total anthocyanin contents of the encapsulated anthocyanin complexes at different temperatures for one year, we found that its change was very small, and even at a higher temperature (35 degrees C), the total anthocyanin content was reduced only 3.11 +/- 0.61% and with no significant difference. We also measured the antioxidant and anti-fatigue activities of the encapsulated anthocyanin after one year's storage and found that they were basically unchanged. Thus, anthocyanin's stability was enhanced significantly after encapsulation.