Investigation into the in vitro release properties of β-carotene in emulsions stabilized by different emulsifiers

- The release of β-carotene in emulsions could be monitored by different emulsifiers.
- Micellarization rate and release of β-carotene in emulsions were evaluated.
- Bile extracts and pancreatin exhibited a synergistic effect on β-carotene micellarization rate.
- The major release of β-carotene in all emulsions occurred in simulated intestine.

Carotenoids may provide a variety of health benefits, however the mechanisms governing their intestinal adsorption are not well understood. The purpose of this study was to identify and evaluate the main factors affecting the release properties of β-carotene in emulsions during the in vitro digestion. Whey protein isolate, Soybean soluble polysaccharides and decaglycerolmonolaurate were used to prepare β-carotene emulsions. The effects of bile extracts, pancreatin, lipase and emulsifiers on the micellarization rate of β-carotene were evaluated and the results demonstrated that bile extracts and pancreatin had a synergistic effect on β-carotene micellarization rate. The maximum amount of potentially bioavailable β-carotene was obtained when the concentration of bile extract and pancreatin was 10 mg/mL and 2.4 mg/mL, respectively. The type of emulsifiers had a significant influence on the release properties of β-carotene in emulsions (p < 0.01). The micellarization rate of β-carotene in emulsions stabilized by Whey protein isolate, decaglycerolmonolaurate and Soybean soluble polysaccharides was 34.0%, 24.1% and 21.8%, respectively. Generally, the Whey protein isolate stabilized emulsion showed the highest release rate in the simulated digestive tract, and the major release of β-carotene occurred in simulated intestine in all emulsions. These findings were significantly important for the design of food delivery systems for increasing carotenoids bioavailability.