Encapsulation of hawthorn flavonoid microcapsules in casein using complex coalescence: development and characterization

Abstract In order to improve the bioactivity of hawthorn flavonoids, a casein-flavonoid microcapsule was prepared. The effect of wall material on the encapsulation rate of flavonoids was investigated, the binding mode of hawthorn flavonoids and casein was explored, and the antioxidant activity and antimicrobial activity of the microcapsules were studied. The results showed that microcapsules prepared by encapsulating hawthorn flavonoids with casein as the wall material showed the highest encapsulation rate of 88.72 ± 1.77%; scanning electron microscopy observation of the microstructure of the microcapsules revealed that hawthorn flavonoids were encapsulated by casein; thermogravimetric analysis showed that the polymerization with casein enhanced the thermal stability of hawthorn flavonoids; and the result of X-ray diffraction, Fourier transform infrared spectroscopy, ultraviolet spectroscopy, and nuclear magnetic hydrogen spectroscopy showed that casein was encapsulated by casein, which was the most important factor for the antioxidant activity and antibacterial activity of the microcapsules. The results showed that casein and hawthorn flavonoids were combined with covalent and non-covalent interaction forces, and molecular docking also confirmed that hawthorn flavonoids and casein formed stable complexes; the antioxidant activity and antimicrobial activity of the casein-flavonoid microcapsules were analyzed, and it was found that the bioactivity of the microcapsules was significantly higher than that of the unencapsulated flavonoids and casein. The study provides an effective way to improve the bioavailability of hawthorn flavonoids and expand their application in food.