Modification of texture and in vitro digestion of pectin and κ-carrageenan food hydrogels with antioxidant properties using plant cells.

The aim of this study was to investigate the relationship between the textural, rheological, and in vitro digestion properties of hydrogels based on pectins with different degree of methylesterification (DM) or κ-carrageenan, and duckweed callus cells, as well as to determine the antioxidant activity of these hydrogels. Encapsulation of cells in the hydrogels resulted in increased grape seed extract (GSE) encapsulation efficiency and porosity of the hydrogels. The incorporation of 40 % cells in pectin hydrogel with low DM (5.7 %) (TVC) resulted in decreased hardness. The incorporation of cells into the weaker pectin hydrogel (DM 33.0 %) (CP) resulted in decreased cohesiveness and springiness and increased hardness, gumminess, and chewiness proportional to the increase in cell concentration. Encapsulation of cells in κ-carrageenan hydrogel resulted in decreased textural characteristics and increased GSE release into saliva. Pectin hydrogels with weaker textural and rheological properties released GSE faster in the gastrointestinal environment compared to those with stronger properties. TVC and κ-carrageenan hydrogels had different mechanisms for GSE release. All samples exhibited the antioxidant activity. Encapsulation of cells resulted in increased radical scavenging activity of hydrogels, enhanced ability to inhibit Fe/ascorbate-initiated lipid peroxidation, and reduced AAPH-induced reactive oxygen species generation in erythrocytes.