Encapsulation provides efficient approaches to increase stability and delivery of poorly soluble bioactive components, predominantly for fortification of beverages and similar liquid-based foods. In this study, folic acid was encapsulated within conventional and emulsion-templated alginate-pectin hydrogels, proliposomes, and a combination thereof. The stability of these systems was examined under various environmental conditions (pH 1.2-9.0, 25-85 °C, dark/light). The techniques demonstrated efficient and relatively straightforward production of well-defined microparticles and nanoparticles (350 nm to 250 μm). Dispersed folic acid provided a delivery system with unique pH-responsive features, which offered prolonged stability during food storage, and indicated increased release at the site of absorption upon ingestion. This formulation had no limitation due to particle size, while at the same time it allowed high encapsulation efficiencies (80%-100%), as compared to the low encapsulation efficiency achieved by solubilisation (6%). At the low pH that is expected in the stomach, leaching of the dispersed folic acid was prevented, while at the pH that is expected in the intestine, there was complete release via solubilisation and carrier swelling. Overall, the optimum for food processing and storage was pH 3.0, where ≥70% of 50% to 200% of the recommended daily allowance of folic acid remained in the alginate-pectin beads after 6 months at room temperature in the dark. The thermal properties were enhanced by emulsion-templated alginate-pectin beads and proliposomes. In this way, 30% to 75% retention of folic acid was achieved at temperatures ≤90 °C, where the proliposomes reinforced within a polysaccharide network achieved the highest level of protection.

中文翻译：

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强化食品中微粒和纳米颗粒中叶酸的热保护和pH门控释放。

包囊提供有效的方法来增加难溶性生物活性成分的稳定性和递送，主要用于饮料和类似液体食品的强化。在这项研究中，叶酸被封装在常规的和乳剂模板的藻酸盐-果胶水凝胶，脂质体及其组合中。在各种环境条件（pH 1.2-9.0、25-85°C，暗/亮）下检查了这些系统的稳定性。该技术证明了有效且相对简单的生产明确定义的微粒和纳米颗粒（350 nm至250μm）。分散的叶酸为输送系统提供了独特的pH响应特性，可延长食品存储期间的稳定性，并表明在摄入时吸收部位的释放增加。与通过增溶实现的低包封效率相比，该制剂不受粒径的限制，同时，它具有较高的包封效率（80％-100％）。在胃中预期的低pH值下，可防止分散叶酸的浸出，而在肠中预期的pH值下，可通过增溶和载体溶胀完全释放出来。总体而言，食品加工和存储的最佳pH值为3.0，在黑暗中于室温放置6个月后，藻酸盐-果胶珠粒中叶酸的推荐日摄入量的50％至200％的≥70％保留在其中。通过乳液模板化的藻酸盐-果胶珠和脂质体增强了热性能。这样，在≤90°C的温度下，叶酸的保留率为30％至75％，