单宁辅色刺葡萄花色苷微胶囊的制备、表征及贮藏稳定性

Preparation,Characterization and Storage Stability of Vitis davidii Foex.Anthocyanin Microcapsules with Tannin as Co-pigment

采用单宁辅色结合微胶囊化的方法实现刺葡萄花色苷的稳态化。选取不同葡萄糖当量(dextrose equivalent,DE)值的麦芽糊精作壁材结合单宁辅色,采用真空冷冻干燥制备刺葡萄花色苷微胶囊。结果表明:DE12麦芽糊精包埋单宁辅色花色苷微胶囊(12-辅色微胶囊)的包埋率最高,达(99.23±0.31)%,其吸湿性和热稳定性也优于其他微胶囊,4种微胶囊的表面形态均呈玻璃状结构,经辅色的花色苷微胶囊的L^(*)值与a^(*)值较未辅色的高,b^(*)值较未辅色的低。差示扫描量热分析表明12-辅色微胶囊具有更高热变性温度,具有更高的热稳定性;傅里叶变换红外光谱确认了辅色花色苷被麦芽糊精成功包埋。12-辅色微胶囊具有良好的缓释性能和抗氧化能力,其在模拟胃消化液中花色苷释放率为(56.84±0.02)%,模拟肠消化液中1,1-二苯基-2-三硝基苯肼自由基清除率(50.15±0.38)%;降解过程符合一级动力学模型,具有较好的贮藏稳定性。同时,在刺葡萄汁加工应用中微胶囊可有效降低巴氏杀菌过程中花色苷的损失。

In this study,co-pigmentation with tannin combined with microencapsulation was used to improve the stability of Vitis davidii Foex.anthocyanin.Anthocyanin microcapsules were prepared by vacuum freeze drying using maltodextrin with different dextrose equivalent(DE)values as the wall material.The results showed that the co-pigmented anthocyanin microcapsules with maltodextrin DE12 had the highest encapsulation efficiency of(99.23±0.31)%and the best hygroscopicity and thermal stability.Scanning electron microscopy(SEM)showed that the surface morphology of all four microcapsules was glassy structure.The co-pigmented anthocyanin microcapsules had higher L^(*)and a^(*)values but lower b^(*)value than the unco-pigmented ones.Differential scanning calorimetry(DSC)analysis showed that the co-pigmented anthocyanin microcapsules with maltodextrin DE12 had higher thermal denaturation temperature and thermal stability.Fourier transform infrared spectroscopy(FTIR)confirmed successful microencapsulation of co-pigmented anthocyanin with maltodextrin.The co-pigmented anthocyanin microcapsules with maltodextrin DE12 had good sustained release performance and strong antioxidant capacity.After simulated gastric digestion,the percentage of anthocyanins released from the microcapsules was only(56.84±0.02)%.After simulated intestinal digestion,the 1,1-diphenyl-2-picrylhydrazyl(DPPH)radical scavenging activity of the microcapsules was(50.15±0.38)%.Moreover,the degradation kinetics of the microcapsules followed first-order kinetics model and the microcapsules had good storage stability.Microencapsulation could effectively reduce the loss of anthocyanins during the pasteurization of V.davidii Foex.grape juice.