Improving the encapsulation of β‐carotene by nanoliposomes via potato starch/whey protein coating

Summary The ability of nanoliposomes (NLs) to encapsulate β‐carotene synergistically improved via the potato starch (PS)/whey protein (WP) coating was investigated. The encapsulation efficiency of PS‐/WP‐coated NL (SP‐NL) increased to above 80% compared to that of NL, PS‐coated NL, and WP‐coated NL. It manifested that the ability of NL to encapsulate β‐carotene was significantly enhanced after coating with PS/WP. The encapsulation ability of SP‐NL was also influenced by environmental factors (pH, temperature, and ionic strength). Moreover, the storage stability of NL after complexation with PS/WP was effectively enhanced compared to that of NL, PS‐coated NL, and WP‐coated NL. TEM images showed that SP‐NL was fairly spherical, and SP‐NL mainly ranged between 100 nm and 500 nm in size. Zeta‐potential and particle size indicated that the dispersion of SP‐NL was highly stable, and electrostatic forces played a vital role in the stability. Furthermore, the fluorescence polarisation of DPH demonstrated that the decrease in membrane fluidity of NL after PS/WP coating was more obvious from 5.28 to 4.05 compared with that of NL after PS or WP coating, indicating that PS/WP was more effective in increasing the rigidity of the phospholipid layer and improving the structure of the bilayer. The present study suggests that PS/WP coating on NL can be an effective strategy to improve the ability of NL to encapsulate β‐carotene and may provide some theoretical support for the development of an effective delivery system for bioactive substances.