钙离子对亚麻籽胶-紫苏分离蛋白负载DHA藻油 乳液储藏特性与递送虾青素效果的影响Effect of calcium ions on storage properties and astaxanthin delivery efficiency of DHA algae oil-loaded emulsion using flaxseed gum-perilla protein isolate

Abstract

DHA藻油是补充ω-3多不饱和脂肪酸的重要非动物来源，但因其自身水溶性差、易氧化产生不良风味等特点，极大约束了其摄入途径。据此，采用高压微射流技术与逐层沉积技术（LBL）制备负载DHA的亚麻籽胶（FG，质量分数为0.4%）-紫苏分离蛋白（PPI，质量分数为0.225%）双层乳液，研究Ca2+添加量（0%～0.5%）对上述双层乳液体系稳定性的影响；同时，采用INFOGEST体外模拟消化模型，探究PPI-DHA藻油单层乳液、FG-PPI-DHA藻油双层乳液、Ca2+-FG-PPI-DHA藻油双层乳液中DHA的消化特性，以及上述3种体系递送虾青素的效率，并通过监测其在消化过程中粒径分布、电荷特性及微观状态变化等解释其内在机理。结果表明：DHA藻油双层乳液储藏20 d后，未添加Ca2+的双层乳液的粒径从10.4 μm降低至4.3 μm，Zeta-电位从-23 mV降低至-33 mV，Ca2+添加量为0.4%的双层乳液的粒径和电位未发生显著变化，乳液液滴分布均匀，无分层、絮凝、沉淀现象；DHA藻油双层乳液储藏20 d后，添加Ca2+的双层乳液的Turbiscan抗重力稳定性指数（TSI）较未添加Ca2+的双层乳液有明显改善；3种乳液体系模拟消化过程中，游离脂肪酸释放量分别为68.88%、50.84%、52.32%，虾青素生物可及性分别为47.42%、12.54%、966%。说明添加Ca2+有利于DHA藻油双层乳液的稳定储藏，但对消化过程中脂肪酸与虾青素的释放具有一定迟缓效果，研究结果可为设计靶向递送体系提供重要理论依据。DHA algae oil is an important non-animal source for supplementing omega-3 polyunsaturated fatty acids (ω-3 PUFA), but due to its poor water solubility and easy oxidation to produce bad flavor, its intake route is greatly restricted. Accordingly, high-pressure micro-jet technology and layer by layer (LBL) were used to prepare DHA-loaded flaxseed gum (FG, mass fraction 0.4%)-perilla protein isolate (PPI, mass fraction 0.225%) double-layer emulsion, focusing on the effect of calcium ion addition (0%-0.5%) on the stability of the above-mentioned double-layer emulsion system. At the same time, the INFOGEST in vitro simulated digestion model was used to explore the digestion characteristics of DHA in PPI -DHA algae oil single-layer emulsion, FG-PPI -DHA algae oil double-layer emulsion, and Ca2+-FG-PPI -DHA algae oil double-layer emulsion, as well as the efficiency of astaxanthin delivery by the above three systems, and its internal mechanism was explained by monitoring its particle size distribution, charge characteristics and microscopic state changes during the digestion process. The results showed that after 20 d storage of the DHA algae oil double-layer emulsion, the particle size and Zeta-potential of the double-layer emulsion without Ca2+ decreased from 10.4 μm to 4.3 μm, from -23 mV to -33 mV, respectively, but for the double-layer emulsion with 0.4% Ca2+ addition，the particle size and Zeta-potential did not change significantly, the emulsion droplets were evenly distributed, and there was no delamination, flocculation, or sedimentation.After 20 d storage of the DHA algae oil double-layer emulsion, the Turbiscan anti-gravity stability index (TSI) of the Ca2+-added double-layer emulsion was significantly improved compared with the non-Ca2+-added double-layer emulsion. During the simulated digestion process of the three emulsion systems, the release of free fatty acids in the three systems was 68.88%, 50.84% and 52.32% respectively, and the bioavailability of astaxanthin in the simulated digestion process was 47.42%, 1254% and 9.66%, respectively. It shows that the addition of Ca2+ is beneficial to the stable storage of the DHA algae oil double-layer emulsion, but has a certain retarding effect on the release of fatty acids and astaxanthin during the digestion. The research results provide an important theoretical basis for designing a targeted delivery system.

Keywords

• dha藻油；虾青素；亚麻籽胶；紫苏分离蛋白；乳液递送体系
• dha algae oil; astaxanthin; flaxseed gum; perilla protein isolate; emulsion delivery system