## 3 Results  
### Encapsulation Efficiency  
The encapsulation efficiency is shown in Table 1. The value of this parameter was dependent on both the type of core and the carrier material. The encapsulation efficiency for microcapsules with a CE core ranged from 8.79 to 17.48%, with a PE core from 29.95 to 74.55%. As can be seen, the Alg + Pect + WPI carrier mixture favored a high blueberry extract-polymer affinity. With higher compound stability and lower transition to the aqueous phase during the crosslinking process, the PE-core microcapsules were characterized. So far, Alg, in combination with proteins or polysaccharides, has been shown to be more effective in binding phenolic compounds than Alg alone [13]. In the case of the addition of polysaccharides and WPI, this phenomenon could be due to a reduction in porosity and the interaction of proteins with phenolic compounds of the extracts, inhibiting their leaching during crosslinking. Moreover, the interactions between the COO\({}^{-}\) Alg and NH\({}_{3}\)\({}^{+}\) groups of WPI could affect the encapsulation efficiency. According to [PERSON] et al. [7], ionic interactions between carboxyl and amino groups in microcapsules allow for the formation of polyelectrolyte complexes with a better ability to control the swelling profile and drug release than Alg or chitosan alone. The differences in encapsulation efficiency can also be attributed to structural interactions in the resulting mixtures, where the hydroxyl groups of phenolic compounds present in blueberry extracts favor the formation of hydrogen bonds with the free carboxyl end groups of the added polysaccharides [36]. In contrast, the lower performance of CE-core microcapsules may have been due to the interaction of the carriers with ballast substances present in the extract, which may have led to the blocking of the binding of phenolic compounds.  
In the available literature, there is a wide divergence in the results for the encapsulation efficiency of gel microcapsules, which mainly depend on the type of carrier materials used and their concentration, the type of core, the dose and phenolic profile, the complexation time, and the concentration of the crosslinking mixture. For plant extracts encapsulated with Alg, with the addition of polysaccharide and/or protein sources, these values range from 8.5 to 93.9% [9; 13; 15], which is consistent with our results. On the other hand, [PERSON] et al. [25] obtained an encapsulation efficiency for blueberry anthocyanins of 87.2% using the response surface area method while concluding that the concentration of CaCl\({}_{2}\) and the dose of anthocyanins in the Alg mixture had the highest effect on this parameter. For comparison, the encapsulation efficiency of blueberry extracts microencapsulated via spray-drying and freeze-drying methods ranged from 70 to 98% [21; 22; 37]. In these methods, maltodextrin, gum Arabic, and WPI were used as wall materials. Nevertheless, the high discrepancy in the results shown indicates the need for further research to, among other things, determine the appropriate concentration of polymers, extracts, and the time of the complexation of the microcapsules in order to maximize the efficiency of this process.