In this study, a ternary complex of zein with lecithin and propylene glycol alginate (PGA) was prepared by an anti-solvent method and applied to encapsulate β-carotene. The structural properties of β-carotene nanoparticles were studied. Moreover, the influences of environmental conditions such as temperature, pH and light on the stability of β-carotene nanoparticles were investigated. The results showed that compared with zein nanoparticles and zein-lecithin complexes, the ternary complex nanoparticles had a higher encapsulation efficiency for β-carotene (93.63%) and showed good stability against temperature and pH. In addition, the ternary complex was extremely effective in inhibiting β-carotene color degradation caused by exposure to ultraviolet light, keeping the average particle size below 250 nm. Therefore, zein-lecithin-propylene glycol alginate nanoparticles are expected to become an effective carrier for hydrophobic compounds.

Lutein, a dietary carotenoid, has various pharmaceutical functions such as protecting retinal pigment epithelial cells from damage caused by blue light, preventing cardiovascular and cerebrovascular diseases and anti-tumor activity. It is also a natural food colorant and antioxidant. The application of lutein in foods is hindered by its poor water solubility, chemical instability, and low oral bioavailability. To solve this problem, delivery systems have been developed. This review discusses the factors limiting lutein application, and summarizes the current status of research on food delivery systems for lutein encapsulation. We anticipate that this review will provide a reference for further research and application of lutein.