This thesis focuses on optimization of simple and complex coacervation of Calendula officinalis extract and its use in model agar confectionery. As part of the coacervation optimization, the influence of pH, polymer concentration, the amount of added extract, and the ratio of polymers on encapsulation efficiency was evaluated; this efficiency was determined by measuring antioxidant activity (ABTS) and the spectrum of volatile compounds.
    In simple coacervation, the encapsulation efficiency reached a maximum value of 47 % at a gelatin concentration of 6% and approximately 60 % at pH 3.5. With higher gelatin concentrations (10 %), the encapsulation efficiency decreased to 15 %. In the case of complex coacervation using a gelatin–gum arabic system, significantly higher efficiencies were achieved, ranging from 5–74 % (ABTS) and 66–92 % (GC-MS). The highest values were recorded at pH 4.2–4.6, a polymer concentration of 5 %, and a higher ratio of gelatin to gum arabic (approx. 1.6–2 : 1).
    The final coacervate was then incorporated into model agar-based confectionery. 21 volatile compounds were identified in the confectionery samples, with sesquiterpenes being the dominant group, primarily ledene (up to 16 %), β-cadinene (up to 13 %), and guaiol (up to 14 %). The antioxidant activity of the samples ranged widely from 69.74 to 731.66 µgTEAC·g⁻¹ (7–78 % radical scavenging), with the highest values observed in the sample where the coacervate was prepared at lower pH (3.8), medium polymer concentration (3 %), and an extract addition of 5 mL. In contrast, samples with the highest encapsulation efficiency showed lower antioxidant activity. No antimicrobial activity against the tested microorganisms (Escherichia coli, Bacillus cereus, Candida glabrata) was demonstrated for any of the samples, likely due to limited release of active substances from the coacervate and poor diffusion into the medium. Texture profile analysis showed that the addition of coacervate had no significant effect on the texture of the confectionery; hardness ranged from 214 to 218 N, gumminess from 34 to 48 N, and cohesiveness from 0.16 to 0.22.
    The results generally confirm that complex coacervation is a suitable and effective method for the encapsulation of bioactive compounds from Calendula officinalis, and the prepared coacervate is suitable for use in food products.