Stability and in vitro digestion of high purity diacylglycerol oil-in-water emulsions

In this study, stability and in vitro digestion of sesame oil-based high purity diacylglycerol (DAG) oil-in-water emulsions were investigated. Firstly, the effects of DAG content and the freeze-thaw process on the physical properties of emulsions were assessed. The fresh DAG emulsions exhibited high absolute zeta-potential values (> 40 mV), small d(4,3) (< 0.94 mu m), and good stability during 14 days storage. However, DAG promoted partial coalescence of fat globules and the creaming index increased after the freeze-thaw process. Subsequently, the in vitro digestion of DAG emulsions was studied. The d(4,3) of emulsions increased from 0.942 mu m, 0.754 mu m and 0.489 mu m to 33 mu m (0 g/kg DAG), 30 mu m (50 g/kg DAG) and 25 mu m (100 g/kg DAG) respectively after digestion in the simulated saliva and stomach, and then decreased to 8 mu m, 7 mu m and 5 mu m respectively in the simulated small intestine. Notably, the variation tendency of zeta-potential was opposite to the d4,3 of emulsions during the simulated digestion. Finally, the free fatty acid release was monitored under simulated intestine digestion and it revealed that higher DAG content favored higher lipolysis. This work sheds light on employing DAG oil to prepare food emulsions.

Automated summary

This study investigated the stability and in vitro digestion of sesame oil-based high purity diacylglycerol (DAG) oil-in-water emulsions. The findings suggest that higher DAG content promotes lipid hydrolysis during simulated digestion, shedding light on the potential use of DAG oil in food emulsions.