Investigation of physicochemical properties and structure of ball milling pretreated modified starch-ferulic acid complexes

In this study, the formation mechanism, physicochemical properties, and intermolecular interactions of ball milling pretreated high amylose corn starch (HACS)-ferulic acid (FA) complexes were elucidated by density functional theory (DFT) calculations, and examined their structural and digestive properties. The results showed that the average molecular weight decreased to 92.155 kDa during ball milling pretreatment. The complexation degree of the ball milling pretreated HACS-FA complexes was increased, the relative crystallinity was increased by 11.74 %, and the short-range ordering was significantly improved. Notably, the content of single helix and double helix showed an increasing trend, indicating that HACS-FA complexes had a more compact V-type structure, which corresponded to a 22.39 % increase in resistant starch. DFT calculations further showed that the intermolecular interactions between HACS and FA were mainly hydrophobic, hydrogen bonding, and van der Waals forces. This study is expected to provide a new method for the efficient preparation of HACS-FA complexes.