Synergistic effects of enzymatic debranching and high hydrostatic pressure on the structural and digestive properties of –conjugated linoleic acid microcapsules

This study explored the effects of enzymatic debranching (ED, 0-12 h) and high hydrostatic pressure (HHP, 300-600 MPa) on the multi-scale structure and in vitro digestibility of lotus seed starch (LS)-conjugated linoleic acid (CLA) microcapsules. XRD revealed diffraction peaks at 7°, 12°, and 20°, characteristic of V-type crystalline complexes formed between amylose and CLA. NMR showed a resonance at 103.5 ppm, while FTIR indicated masking of CLA double bonds, confirming successful complexation. Microcapsules treated at 300 MPa for 6 h exhibited the highest microcrystalline proportion (31.2%). In vitro digestion showed that the 6 h + 300 MPa group retained 25.5% resistant starch, significantly higher than the 0 h + 300 MPa group (9.6%). SEM revealed spherical resistant starch clusters, contributing to the delayed release of CLA. These findings demonstrated the potential of ED and HHP to produce stable, targeted starch-based microcapsules for heat-sensitive bioactives, offering a sustainable alternative to conventional thermal processing.