Effects of dynamic high-pressure microfluidization treatment on the structural, physicochemical, and digestive properties of wheat starch-Lonicera caerulea berry polyphenol complex

Polyphenol complexes can improve the physicochemical and functional properties of starch. In this study, a wheat starch-Lonicera caerulea berry polyphenol complex (WS-LCBP) was prepared using dynamic high-pressure microfluidization (DHPM). The effects of different DHPM pressures (150 and 250 MPa), number of cycles (1 and 3), and LCBP content (0 %, 6 %, 8 %, and 10 %) on the multiscale structure, physicochemical properties, and in vitro digestibility of WS-LCBP were examined. After a single 250 MPa DHPM cycle, Average particle size and water separation rate of WS were reduced by 42.40 % and 16.67 %, the freeze-thaw stability was significantly improved (P < 0.05), and the resistant starch (RS) content 68.67 % was significantly increased (P < 0.05). WS-LCBP has a V-shaped starch structure, which hinders gelatinization and increases enthalpy. The RS content of the WS-LCBP ranged from 72.46 % to 89.09 %, which was significantly higher (P < 0.05) than that of wheat starch subjected to a single 150 MPa DHPM cycle (36.31 %). Three 250 MPa DHPM cycles were beneficial for the formation of WS-LCBP. However, excessive DHPM treatment pressure and frequency reduced the recombination rate of LCBP and wheat starch. This study provides reference data for the industrial production of nutritionally functional wheat-resistant starch using green technologies.