## 4 Discussion
On one hand, electrostatic interactions among the dissociated carboxylic groups of alginate and the flavylium cations of the anthocyanin can have a stabilizing effect on anthocyanins [44], but also, covalent bonds among alginate, pullulan, and anthocyanins and some phenolics are formed, as was already observed between pectin-alginate and anthocyanins [19], enhancing the stability of anthocyanins and some phenolics during the formation of hydrogel beads. For better comprehension of the interactions among anthocyanins and polysaccharides, one needs to keep in mind that, firstly, these compounds are interconnected, and the following binding involves the creation of a so-called stacking impact, which leads to the attachment of additional anthocyanin molecules to those already bonded with polysaccharides [45]. This effect was observed for both anthocyanins in the encapsulation mixture of alginate and pullulan, alginate and disaccharides, and alginate/pullulan/trehalose. However, the opposite effect was observed for other phenolics; the addition of disaccharides in combination with both polysaccharides highly affected those interactions, especially negatively for neochlorogenic acid and quercetin-3-glucoside. The utilization of mixtures consisting of large polysaccharides and small disaccharides ensures tight molecular packaging, i.e., disaccharides fill gaps that are formed by polysaccharide [46]. While this effect can aid in the entrapment of some polyphenol molecules, at the same time, it can decrease the number of biding sites for others. Possible interactions among compounds that provided the chemical entrapment of polyphenols in the matrix of beads are one clarification; however, disaccharides can also be involved in changing water dynamics and through this course influencing the entrapment of phenolic compounds. We used two disaccharides in the encapsulation mixture, sucrose and trehalose, which are chemical isomers. However, their impact on the encapsulation of not only anthocyanins but also other phenolic compounds was different regardless of if they were used alongside alginate or in combination with alginate and pullulan. Both anthocyanins were estimated to have higher concentrations in hydrogel beads when trehalose was added to the encapsulation mixture alongside alginate or alginate and pullulan. There was no difference in the effect of disaccharide type on the encapsulation of quercetin-3-utinoside, whereas an impact was detected on phenolic acids. Even though chlorogenic and neochlorogenic acids are isomers, the impact of disaccharide was diverse. When disaccharides were added to the encapsulation mixture alongside alginate, neochlorogenic acid was determined in higher concentrations in hydrogel beads with sucrose and chlorogenic acid in hydrogel beads with trehalose. Interestingly, a reverse effect was observed when disaccharides were added to the encapsulation mixture alongside alginate and pullulan. Although the investigated disaccharides are chemical isomers, based on some parameters such as the formation of clusters, the radius of gyration, the hydration number, and the glycosidic dihedral angles, it was deduced that trehalose water solutions were more homogenous in comparison sucrose ones [47]. Trehalose has a larger impact on water structure because it binds with more molecules of water than sucrose, thus having a larger destructuring impact on water [48]. Disaccharides cause the development of steric hindrance in water, which can cause protection from or slowing down of the nucleophilic attacks of water on anthocyanins. Additionally, trehalose has higher stability towards hydrolysis than sucrose [49]. These properties were probably more expressed in encapsulation mixtures with the addition of trehalose, causing higher encapsulation of anthocyanins. Also, it can be expected that interactions between some phenolics and trehalose can occur. It was proven that the creation of stable intramolecular complexes among trehalose and specific unsaturated compounds can occur.