Formation and sucrose release properties of pectin/κ-carrageenan composite gel: effects from chicory dietary fiber addition

Sucrose release is linked to sweetness perception and key to the design of sugar-reduced foods. In the present study, the gelation, rheological properties, and microstructure of pectin/κ-carrageenan composite gel incorporated with sucrose and chicory dietary fiber (CDF) were investigated via dynamic rheological tests, texture profile analysis, and scanning electron microscopy (SEM). Subsequently, the effects of CDF addition on sucrose release characteristics from the composite gels were explored. Incorporation of sucrose (8–15 %) and CDF (0.2–0.6 %) elevated the gelation temperature from 39.6 to 61.1 °C (for sugar addition), and from 44.5 to 52.9 °C (for CDF addition), respectively. The CDF molecules integrated into the polysaccharide network structure by binding with carrageenan or pectin, enhancing the composite gel matrix. Furthermore, a denser and more brittle network structure was formed. These structural features caused the gel to fracture into smaller pieces during the simulated mastication. This could increase the gel’s surface area exposed to water, thereby enhancing the migration of sucrose molecules into the aqueous phase. The modulation of sucrose release from gel matrix to external environment could be a useful method to enhance sweetness. This finding suggests a potential way to reduce sugar content in gel foods while maintaining sweetness perception.