Synthesis of a novel starch-based emulsion gel with remarkable low-temperature stability via esterification, ozone-oxidation and ion induction.

A novel starch-based emulsion gel was designed via octenyl succinic anhydride (OSA) esterification, ozone oxidation, and ion (Ca) induction. The gel properties and low-temperature stability of emulsion gel with different oxidation time (0, 5, 10, 15, 25 min; OW-0, 5, 10, 15, 25) were systematically investigated. FTIR revealed that the oxidation of CC and -OH groups in OW-0 by ozone oxidation led to their cleavage into carbonyl groups, and than transformed to carboxyl groups. Moreover, oxidation treatment changed the amorphous and crystal region of starch, resulting in the increasing extensibility, leaching of short chains, and charged groups. The presence of extended starch chains, leaching of short starch chains, and Ca facilitated the formation of the promoting interaction between starch molecular chains, thereby developing a highly cross-linked network structure. Remarkably, a more compact gel network structure was formed through the interaction between water molecules and modified starch in the emulsion gel for OW-15. Furthermore, the gel network structure endowed the emulsion with thick, dense layers on the condensed surface, enhancing its stability at low temperatures. This research provides a novel strategy for designing the starch-based emulsion gel, holding promising applications in the food industry and other scientific fields.