High internal phase emulsions stabilized by fluorescent phycocyanin for improved stability and bioaccessibility of β‐carotene

Abstract BACKGROUND High internal phase emulsions (HIPE) are distinguished from ordinary emulsions by higher oil‐phase percentage and better storage stability. Recently, HIPE stabilized with protein‐based particles has received more attention. However, organic precipitation, chemical cross‐linking and thermal denaturation are often needed to stabilize emulsions with natural proteins, and there is an urgent need to reduce the pollution of organic reagents. RESULTS HIPE loaded with β‐carotene stabilized by phycocyanin was prepared under mild conditions. It demonstrated strong stability in terms of temperature and storage, as evidenced by its 94.17% retention rate and 81.06% bioavailability. This stability was ascribed to the efficient defense against heat and UV rays, which was probably associated with the oil‐droplet environment and interfacial protection of phycocyanin. It is speculated that the possible main interaction site between phycocyanin and sorbitol exists near amino acids 110 to 120 of the B chain. The hydrogen bond and hydrophobic interaction between them make the phycocyanin fully adsorbed on the oil–water interface when sorbitol is stable, forming a strong oil–water structure, which increases the stability of the emulsion. CONCLUSION The outstanding fluorescence characteristics provide a feasible alternative for fluorescent emulsions to distribute and trace active compounds in vitro . HIPE loaded with β‐carotene might have potential as a 3D printing material for edible functional foods. © 2024 Society of Chemical Industry.