Improved physicochemical stability and bioaccessibility of astaxanthin-loaded oil-in-water emulsions by a casein-caffeic acid-glucose ternary conjugate

In this study, the influence of casein-caffeic acid-glucose ternary conjugate (CSC) on the physicochemical properties and bioaccessibility of astaxanthin-loaded emulsion was investigated and compared with sodium caseinate (CSN), a synthetic emulsifier commonly used in the food industry. The CSC-stabilized emulsion exhibits droplet characteristics similar to CSN-stabilized emulsion, and can effectively resist the external forces that lead to the phase separation of the emulsion. Although phase separation also occurred at pH 4.0, CSC emulsion had a wider range of pH stability (pH 3.0, 5.0-8.0) and higher salt ion stability than CSN emulsion. Furthermore, CSCstabilized astaxanthin emulsions showed better astaxanthin protection under different heat treatment conditions and storage temperatures compared with CSN. After 28 days of storage at 4 degrees C, astaxanthin residues in the CSCstabilized emulsion reached 92.37 %. The bioaccessibility of astaxanthin in CSC-stabilized emulsion was 26.21 %, much higher than that in CSN (6.47 %). This research study provides a platform for designing astaxanthinfortified food or beverage systems to achieve better stability and delivery to target sites.

Automated summary

In this study, the impact of casein-caffeic acid-glucose ternary conjugate (CSC) on the physicochemical properties and bioaccessibility of astaxanthin-loaded emulsion was investigated and compared with a commonly used synthetic emulsifier, sodium caseinate (CSN). The results showed that CSC-stabilized emulsion had similar droplet characteristics to CSN-stabilized emulsion and exhibited better stability under different conditions. CSC-stabilized emulsion also showed higher astaxanthin protection and bioaccessibility compared with CSN. This study provides a platform for designing astaxanthin-fortified food or beverage systems with improved stability and targeted delivery.