Octenylsuccinic anhydride is an important starch esterification modifier. The octenylsuccinic acid starch esters prepared from it possess an amphiphilic structure that combines both hydrophilic and hydrophobic properties, offering broad application prospects in the food, pharmaceutical and cosmetics sectors.

1. Emulsifiers and stabilisers represent the primary applications of OSA starch esters in the food industry. Owing to their amphiphilic structure, OSA starch esters can effectively reduce interfacial tension between oil and water, forming stable emulsion systems, and are widely used as emulsifiers in both water-in-oil and oil-in-water emulsion systems. In studies on OSA-modified cassava starch-based Pickering emulsions, the smallest emulsion particle size (3.59 μm) was observed when the OSTS addition was 5% and the oil phase volume fraction was 50%; no phase separation occurred during a 60-day storage period.

2. Microcapsule wall materials represent another important application of OSA starch esters. As the introduction of OSA renders hydrophilic starch hydrophobic, OSAS possesses amphiphilic properties (both hydrophilic and lipophilic). When used as microcapsule wall materials, they effectively protect the core material from inactivation and oxidation caused by external factors, thereby enabling controlled release of the core material. Oil microcapsule particles prepared using the spray-drying method with octenyl succinic acid starch ester as the shell material offer advantages such as excellent encapsulation efficiency and low surface oil content.

4. Pickering emulsion stabilisers have been a research focus of considerable interest in recent years. OSA-modified starch can serve as a solid particle stabiliser to construct Pickering emulsions; such emulsions exhibit excellent stability and are environmentally friendly. Research on hydrophobic-modified oat starch indicates that the stability of OSA-modified oat starch is significantly greater than that of unmodified oat starch, and it can maintain emulsion stability over a wide pH range (3–9) and under certain ionic strength conditions.