β-胡萝卜素乳液凝胶微球制备与理化特性研究

Preparation,Characterization and Physicochemical Properties ofβ-carotene Emulsion Gel Microspheres

β-胡萝卜素作为重要的生物活性物质,其稳定性差、生物利用率低,极大限制了其在食品领域的应用。以大豆分离蛋白为水相,以玉米油为油相,通过添加壳聚糖、海藻酸钠制备多层乳液,与Ca^(2+)交联制备运载β-胡萝卜素凝胶微球。通过粒径、ζ-电位、乳化稳定性、界面蛋白吸附量、β-胡萝卜素包埋率等指标和扫描电镜观察、红外光谱分析、体外释放动力学实验,研究了壳聚糖、海藻酸钠质量分数对乳液稳定特性及β-胡萝卜素凝胶微球释放特性的影响。结果表明,当壳聚糖质量分数为2.0%时,形成的双层乳液稳定性最好,对β-胡萝卜素的包埋率最高,达(64.82±0.31)%;当海藻酸钠质量分数达到2.0%时,形成的三层乳液对β-胡萝卜素包埋率最高,达到(86.75±2.00)%。红外光谱分析表明,凝胶微球中海藻酸钠与壳聚糖发生了静电相互作用;扫描电镜观察表明,干燥的凝胶微球呈球形,且随海藻酸钠质量分数的增加,凝胶微球的结构变得更加紧密;体外释放实验证明,凝胶珠微球具有持续性释放的功能,乳液凝胶微球可作为β-胡萝卜素一种良好的缓释体系。

As an important biologically active substance,β-carotene has poor stability and low bioavailability,which greatly limits its application in food.Soybean protein isolate(SPI)was used as water phase,corn oil as oil phase to form a multilayer emulsion with chitosan and sodium alginate,which was cross-linked with Ca^(2+)to prepareβ-carotene microspheres.The effects of mass fractions of chitosan and sodium alginate on the stability andβ-carotene release characteristics of emulsion and gel microspheres were studied by analyzing the particle size,ζ-potential,emulsification stability,interfacial protein adsorption capacity,embedding rate ofβ-carotene,scanning electron microscope,Fourier transform infrared spectroscopy and in vitro release.The results showed that when the mass fractions of chitosan was 2.0%,the stability of the secondary emulsion was the best,and the embedding rate ofβ-carotene was up to(64.82±0.31)%,when the mass fractions of of sodium alginate reached 2.0%,the embedding efficiency ofβ-carotene in the three-layer emulsion was significantly increased,with the value of(86.75±2.00)%.The Fourier transform infrared spectroscopy(FTIR)indicated the electrostatic interaction between sodium alginate and chitosan.The dried gel microspheres were spherical and the structure of gel microspheres became more compact with the increase of sodium alginate concentration.In addition,in vitro release experiments showed that the gel microspheres had the function of continuous release.Emulsion gel microspheres can be used as a potential sustained-release system forβ-carotene.