Formation and gastrointestinal digestion of β-carotene emulsion stabilized by milk fat globule membrane

In the present study, milk fat globule membrane (MFGM) was used to prepare beta-carotene emulsion. The physicochemical and microstructure changes of MFGM-prepared emulsions were investigated upon exposure to gastrointestinal (GI) digestion fluid. The average droplet size significantly reduced (p < .05) from 18.29 mu m to 0.91 mu m with the addition of MFGM concentrations from 0.25 wt% to 4.0 wt%. The emulsion exposure to the simulated gastric fluid showed a significant increase in droplet sizes (p < .05) and partial droplet aggregation in microstructure compared to initial emulsion. There was a notable increase (p < .05) in particle sizes and decrease in the number of oil droplets when beta-carotene emulsion was exposed to simulated intestinal fluid after 60, 120, and 180 min digestion time. In the simulated intestinal fluid, about 200 mu mol/L free fatty acid and 60% beta-carotene were released when beta-carotene emulsion was exposed to simulated intestinal fluid after 60 min digestion time. Practical applications Milk fat globule membrane (MFGM) is an ideal material used for the preparation of beta-carotene emulsions because of not only its fascinating structure and special compositions but also its nutritional and health benefits. In this work, MFGM stabilizes the oil phase, as well as controlling and triggering the release of beta-carotene when the emulsions are exposed to GI tract. Therefore, these results demonstrate that MFGM as a natural emulsifier can be used to deliver hydrophobic bioactivities.