This study discusses the relationship between the structural properties of the selected polysaccharides (low (ALGLV) and medium viscosity (ALGMV) sodium alginate, 90 kDa (CMC90) and 250 kDa (CMC250) carboxymethyl cellulose, and κ-carrageenan (CARκ)) and their abilities to serve as protective materials of encapsulated large cranberry (Vaccinium macrocarpon Aiton) fruit extract (CE) from losing its health beneficial activities during long-term storage. The microparticles were characterized in terms of their encapsulation efficiency (UV-Vis and FTIR), morphology (SEM) and the physical stability in various environments (gravimetry). The microparticles' size and encapsulation efficiency were 46-50 µm and 28-58%, respectively, and the microparticles were physically stable. CMC90 and ALGMV most efficiently protected the plant extract from losing its biological activity after 18 months, while the plant extract stored outside the particles had lost its activity. CE was intended for oral administration, thus CE release from the microparticles was monitored in vitro under gastrointestinal conditions. In vitro gastrointestinal release studies revealed that the ALGMV-, CMC90-, and CMC250-based particles exhibited the desired intestinal release pattern. This result supports the suitability of sodium alginate and carboxymethyl cellulose for the safe delivery of CE to the intestines while maintaining its biological properties and improving long-term storage stability.
Keywords: Vaccinium macrocarpon Aiton; antioxidant activity; encapsulation; fruit extract; hydrogel; long-term storage.