Evaluating structural properties and stable sustained release mechanism of ω-3 fatty acid enriched microcapsules prepared with multi-component composite wall materials

Abstract

This study used microcapsule technology to enhance the storage stability and oxidation stability of ω-3 fatty acids. Using the embedding as the index, we screened ω-3 fatty acid microcapsules prepared with various wall materials. Results demonstrate that different wall materials significantly impact the embedding rate of ω-3 fatty acid enriched oil, with quaternary microcapsules (94 ± 1.02%) > ternary microcapsules (≤89 ± 1.27%) > binary microcapsules (≤72 ± 0.83%). FT-IR results showed that the multi-composite wall material effectively embedded the composite oil; TG-DSC and GC-MS show that ω-3 fatty acid microcapsules possess excellent heat resistance, with retention rates of 97.89 ± 0.31% and 97.41 ± 0.47% for EPA and DHA, respectively. Accelerated storage studies indicated that the core material retention rates of microcapsules were 92.71 ± 0.9%, 86.91 ± 0.87% and 75.09 ± 0.88% at 5 °C, 25 °C, 50 °C after 20 days of storage, respectively. Microcapsules significantly improved oxidation resistance, with quaternary microcapsules outperforming ternary microcapsules. The in vitro simulated digestion results demonstrated that the ternary and quaternary microcapsules were slowly and slightly released in the gastric digestion stage with rates of 29.43 ± 1.19% and 22.64 ± 1.50%, respectively. The core material is predominantly released in the intestine, and the Quaternary microcapsules possess better sustained-release effects compared to the ternary microcapsules.