In this thesis, we test whether an ionotropic gel (made of a mixture of alginate and pectin) is able to effectively retain ascorbic and folic acid. The aim of the thesis is to prepare stable microcapsules with ascorbic and folic acid, achieving a high encapsulation efficiency and meeting the recommended daily intake for both components with an appropriate capsule ratio. We monitored the encapsulation efficiency, the release of the bioactive components into the CaCl2 solution, the release of both bioactive components under simulated gastrointestinal conditions and looked at the microcapsules under a microscope. Folic acid was successfully encapsulated, achieving a high efficiency (99%), while ascorbic acid encapsulation reached 25% efficiency. Ascorbic acid was released within a time window of 20 min, while folic acid remained stable for several days. In both cases, the recommended daily intake was achieved with the appropriate capsule weight. The release of folic acid was lower under acidic conditions, while it was higher under alkaline conditions. At lower pH, folic acid is immobilised and trapped in the network of the carrier material, whereas at higher pH the carrier material (alginate) becomes negatively charged, causing swelling and release of FA. In addition, the solubility of FA is higher at alkaline pH. The release of FA was pH dependent, as differences in release were observed at different pH (2,0, 5,0, 7,0). The fastest release of AA was at pH 7,0, it is known that ascorbic acid in free solution becomes less stable as the pH approaches neutral, but it should be noted that there was no significant difference as most of the AA was lost within a time frame of 20 min at all three pH values.
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