Preparation and Physicochemical Properties of Hawthorn Polyphenol Microcapsules

In order to improve the stability and bioavailability, hawthorn polyphenols microcapsules were prepared by spray drying using β-cyclodextrin. Whey protein isolate and gum Arabic as concentrations wall materials, and hawthorn polyphenols as the core material. The particle size, microscopic appearance, stability, sustained release and antioxidant properties of the microcapsules were analyzed. The results showed that core-to-wall-material ratio was 1:3 (v/v), air inlet temperature was 165 ℃ and emulsification time was 11.4 min as the optimum preparation process. Under all conditions optimized, the encapsulation rate was 94.45%±1.03% and the drug loading was 17.99%±0.20% of hawthorn polyphenol microcapsules, which average particle size was 6.77 μm, the microcapsules gained complete particles and spherical structure. The microcapsules showed well stability in gastric juice and well release performance in intestinal juice. The release rates of hawthorn polyphenols and hawthorn polyphenol microcapsules after 2 h of simulated gastric juice digestion were 13.38% and 9.75%, respectively, and 6 h after intestinal juice digestion were 95.99% and 72.53%, respectively. The oxidations resistance and stabilities were improved obviously after encapsulation. The IC₅₀ values of hawthorn polyphenols for DPPH, OH, O₂⁻ free radical scavenging rates were 12.669 μg/mL and 1.131, 0.581 mg/mL, respectively, and the hawthorn polyphenol microcapsules were 0.939 μg/mL and 0.129, 0.546 mg/mL, respectively. After 10 days of light exposure, the retention rates of hawthorn polyphenols and hawthorn polyphenols microcapsules were 64.99% and 86.74%, respectively. The retention rates at 80°C were 70.77% and 88.77%, respectively, and the retention rates of hawthorn polyphenols and hawthorn polyphenols microcapsules stored without packaging for 28 days were 73.48% and 91.15%, respectively. These above results indicated that microcapsule technology could improve the stability, sustained release and antioxidant activities of hawthorn polyphenols, and could be used as an effective method to improve the processing stability of hawthorn polyphenols.