The beneficial effects of probiotics on host health have been widely documented. Although the market is flooded with probiotic products, studies often show that the available probiotic strains do not meet the requirements for probiotics. One of the main criteria is a high survival rate during passage through the host gastrointestinal tract in order to exert beneficial effects at the target site. Because probiotics must survive these stressful conditions, techniques that protect the cells with non-toxic biopolymers are often used. An example of the use of such a matrix is microencapsulation in an alginate carrier. In addition, it is important to extend the shelf life of probiotic products. Therefore, freeze-drying techniques are used to allow longer storage. In addition to basic probiotic properties, certain functional properties are often desired. For example, recent studies recommend the consumption of products with high antioxidant potential, as they have many beneficial effects on health. In this work, probiotic bacteria (Lactobacillus plantarum M2 and Lactobacillus plantarum KO9) were encapsulated and freeze-dried. Freeze-dried microcapsules of these strains showed a high survival rate under simulated gastrointestinal tract conditions and were a suitable carrier for L-ascorbic acid, which increased the antioxidant capacity of the final product. The basic antioxidant activity of formed capsules, expressed as the ability to remove DPPH radicals, was determined. Since L-ascorbic acid has potential antimicrobial activity, its effect on the growth of selected pathogenic bacteria, such as Salmonella typhimurium, Escherichia coli, Staphylococcus aureus, and Listeria monocytogenes was investigated. This study shows how microencapsulation of probiotics with the addition of desired biological molecules can enhance the beneficial functional properties of probiotics.