Effects and mechanism of high-pressure homogenization on the characterization and digestion behavior of lotus seed starch–green tea polyphenol complexes

Lotus seed starch (LS) suspensions (3%, w/v) with added green tea polyphenols (GTPs; 10%, w/w) were subjected to five passes of high-pressure homogenization (HPH). The effects of HPH treatment on the physicochemical properties of the LS–GTP system were studied. GTPs affected the physicochemical properties of starch (granule size, crystallization, morphology, and thermal properties) to varying degrees depending on the pressure of HPH. LS-GTP complexes exhibited a C-type crystalline structure and showed a “reticular” surface structure at <150 MPa, called non-inclusive complex. More complexes with ordered V-type crystalline host lattice formed at >150 MPa, with an irregular “flower-like” structures formed by many small spherical crystalline, called V-type inclusion complexes. Furthermore, the complexes on the surface of starch granules acting as a barrier against enzyme contact with the substrate and displayed a strong enzymatic resistance via a dynamic in vitro rat stomach–duodenum (DIVRSD) model.