The aim of the work was to formulate an encapsulation system for protection of bioactive compounds of aqueous saffron extract in dairy products. We encapsulated the saffron extract into free casein micelles and casein micelles with binded polysaccharide alginate and pectin respectively at different ratios of extract compared to wall material (5 %, 10 %, 15 %, 20 %) and dried it with freeze or spray drying. Encapsulation efficiency, particle diameter and zeta potential were analyzed for described samples (and also free casein micelles and free saffron extract). Interactions between molecules of extract and wall material were determined with FTIR spectrophotometry, antioxidant capacity of prepared samples with ABTS method, stability of three major saffron bioactive compounds (crocin, picrocrocin and safranal) during storage at different conditions was analyzed using UV/VIS spectrometry. The optimal stability (during cold storage) was determined for samples that were stored in dry form and were not suspended in dairy yoghurt or milliQ water with pH value of dairy yoghurt or bovine milk. In all studied cases were the analyzed bioactive compounds in samples of encapsulated saffron extract more stable compared to samples of free saffron extract. We also determined that the stability of studied bioactive compounds is affected by (i) the storage temperature, as stability was longer for cold stored samples in comparison with storage at room temperature; (ii) drying method, as longer stability was achieved with freeze drying compared to spray drying.
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