Utilization of Yeast Cells as Alternative Carriers in the Microencapsulation of Black Chokeberry (Aronia melanocarpa) Phenolic Extract

The structure of yeast cells, which are rich in bioactive compounds, makes them an attractive encapsulation vehicle due to their antioxidant, antibacterial, and antimutagenic properties. In this study, black chokeberry extract was encapsulated with different wall materials (maltodextrin, gum arabic, mixture of maltodextrin and gum arabic, plasmolyzed yeast, and non-plasmolyzed yeast) by freeze-drying. While the highest encapsulation efficiency was obtained with maltodextrin (98.82%), non-plasmolyzed yeast (86.58%) emerged as a viable alternative to gum arabic. The largest particle size was observed in plasmolyzed yeast microcapsules. Yeast-coated capsules exhibited a spheroidal morphology. Differential Scanning Calorimetry revealed high thermal stability for all microcapsules, with the gum arabic-coated microcapsules demonstrating the greatest stability. After the simulated gastric and intestinal fluid treatment, plasmolyzed yeast provided the highest retention, with 63.45% and 77.55% of phenolics, respectively. The highest 2,2-Diphenyl-1-picrylhydrazyl (DPPH) activities were found in yeast microcapsules, with no significant difference between them. In 2,2'-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS^•+) scavenging activity, the least loss (approximately 10%) was observed in non-plasmolyzed yeast samples after intestinal digestion. These results showed that yeast can be used as an alternative coating material in the encapsulation of phenolics, and it contributes to the bioavailability of microcapsules with its protective effect during digestion.