Insight into esterified and granular esterified-pregelatinized starch formation during esterification modification: Key role of temperature.

The formation conditions and functional property differences of esterified starch (ES) and granular esterified-pregelatinized starch (EPS) synchronously prepared by octenyl succinic anhydride (OSA) modification remain unclear. In this study, we explored the formation conditions and physicochemical properties of ES and EPS after OSA modification. The modification temperature controlled the formation amount and time for both starch types during OSA modification. Compared to ES, EPS exhibited a higher degree of substitution, cold-water swelling power, water-absorption capacity and apparent viscosity in cold water. The structural characterization confirmed the molecular weight and short/long-range molecular order of ES and EPS decreased. Moreover, scanning electron microscopy indicated EPS retained its granular morphology. The X-ray diffraction patterns confirmed the presence of more starch-lipid complexes formed in EPS than in ES. This study provides a novel method for preparing esterified and granularly esterified-pregelatinized starches that could be used as promising additives in low-energy formula foods.