Enhancement of capsanthin emulsions stabilized by soy protein isolate-xanthan gum complexes on the conformational changes, gelation properties and storage stability of myofibrillar protein.

This study investigated the gel-forming capacity and storage stability of myofibrillar protein (MP) affected by capsanthin emulsions (SXCEs) stabilized by soy protein isolate (SPI) and xanthan gum (XG). SPI-XG formed a stable interfacial layer through hydrophobic interactions and hydrogen bonding, increasing emulsifying activity index (EAI) and emulsifying stability index (ESI) by approximately 16.2% and 62.7%, respectively. Capsanthin and SXCEs promoted ordered MP conformational transitions toward β-sheet structures, strengthened hydrophobic interactions and disulfide bond formation, and facilitated the formation of a compact gel network, improving hardness, elasticity, and chewiness by 69.55%, 15.64%, and 62.28%, respectively. During storage, capsanthin inhibited lipid oxidation, with MDA decreasing from 1.12 mg/kg in the Control group to 0.59 mg/kg in the SXCE group on day 7. Overall, SXCE not only improved the emulsification and dispersibility of capsanthin (CAP) but also enhanced the gelling properties and storage stability of MP gel products.