Cryostructuring as a Strategy to Enhance the Water and Oil Absorption Capacities of Chayotextle (Sechium edule) Starch

Starch cryostructuring is a promising strategy for improving starch functionality for food applications. However, information on the structural and functional changes of chayotextle (Sechium edule) starch after cryostructuring remains limited. Therefore, this study evaluated the effect of cryostructuring on the physicochemical, structural, and functional properties of chayotextle starch.

Native starch isolated from chayotextle was gelatinized, cryostructured by freezing, and subsequently freeze-dried. Apparent density, water absorption capacity (WAC), oil absorption capacity (OAC), and Fourier transform infrared spectroscopy (FTIR) were evaluated.

Cryostructuring markedly reduced the apparent density from 0.8574 ± 0.0209 to 0.3141 ± 0.0029 g mL⁻¹, accompanied by substantial improvements in starch functionality. Water absorption capacity increased from 1.90 ± 0.14 to 4.85 ± 0.07 g∙ g⁻¹, whereas oil absorption capacity increased from 2.80 ± 0.10 to 4.97 ± 0.06 g∙g⁻¹. These results suggest that cryostructuring promoted structural rearrangements that enhanced the interaction of starch with both aqueous and lipid phases, consistent with the porous architectures commonly reported for cryostructured starch systems.

FTIR analysis indicated that cryostructuring preserved the chemical identity of the starch, while slight band shifts and intensity variations suggested hydrogen-bond rearrangement, increased bound water, and molecular reorganization associated with partial retrogradation rather than chemical modification. Overall, cryostructuring improved the functional performance of chayotextle starch while maintaining its chemical structure, demonstrating its potential as a starch-based functional ingredient for food applications.