Structural characterisation and adsorption properties of cross‐linked esterified broken rice porous starch.

Summary: In order to improve the adsorption properties and stability of porous starch, the porous starch made from ground rice starch was doubly modified by cross‐linking and esterification using sodium trimetaphosphate (STMP) as a cross‐linking agent and octenyl succinic anhydride (OSA) as an esterifying agent. Structural analysis of the samples showed that the phosphate group in STMP formed a new P‐O‐C covalent bond with the hydroxyl group in starch by substitution, OSA combined with the hydroxyl group of starch formed an ester carbonyl group, and all cross‐linking and esterification occurred in the amorphous region of starch. DSC and TG/DTG analysis showed that STMP modification performed better than OSA modification in thermal stability. However, by analysis of the oil absorption properties and freeze–thaw stability, the OSA‐modified porous starch exhibited better oil‐holding rate and freeze–thaw stability. [ABSTRACT FROM AUTHOR]