Effects of concurrent ball milling and octenyl succinylation on structure and physicochemical properties of starch

•Ball milling-octenyl succinylation (BM/OSA) influenced starch structure/properties.•BM/OSA caused structural disruption to starch granule and crystallites.•BM/OSA changed the starch rheological behavior from pseudo-plastic to Newtonian.•BM/OSA enhanced starch paste stability during shear, heating and cooling.•BM/OSA reduced paste viscosity and rigidity regardless of substitution degree.

This work concerns the effects of concurrent ball milling (BM) and octenyl succinic anhydride (OSA) modification on the starch microstructure and physicochemical properties (swelling, emulsifying, and rheological). Unlike normal OSA-modified starches, the BM/OSA-modified starch displayed new features such as reduced viscosity and rigidity but increased paste stability during shearing, heating and cooling, regardless of the substitution degree. More interestingly, while the physicochemical properties could be regulated by simply altering the BM treatment time, BM/OSA was more efficient and effective at modulating starch properties during the initial period (approx. 10 h), as seen by the rapid evolutions in starch structural disruption and OSA esterification. Thus, the BM/OSA modification can serve as a viable and cost-effective approach for producing octenyl succinate starches where low viscosity (at relatively high concentrations) and high paste stability are desired.