Study on stability and in vitro digestion property of Lutein Pickering emulsions encapsulated with whey protein isolate /sodium alginate/tea polyphenols

Lutein has high nutritional value and plays a variety of physiological functions, particularly in terms of eye protection. It presents potential value for the development of functional foods. However, different environmental factors can significantly influence the properties of lutein. In this study, we utilized whey protein isolate (WPI), sodium alginate (SA), and tea polyphenols (TP) as ternary solid particles to fabricate Pickering emulsions that encapsulate lutein through non-covalent interactions. We examined the retention rate of lutein, microstructure, and rheological properties. The light stability, thermal stability, and storage stability were determined. Additionally, an in vitro digestion model was established. These results demonstrated that WPI-SA-TP composite particles encapsulated lutein Pickering emulsions showed a uniform droplet distribution and possessed an elastic gel structure. The retention rate of lutein remained high after exposure to UV irradiation, heat, and storage for 30 days. During in vitro simulated digestion experiments under gastrointestinal conditions, the bioaccessibility and free fatty acid release rate of lutein were determined to be 14.6% and 13.55%, respectively. Therefore, the mentioned Pickering emulsions efficiently deliver lutein while providing potential insights for the development of other functional nutrient delivery systems.

Graphical Abstract