Enhancing the nutritional value and caliber of silver carp surimi by adding β-carotene: Insights into the gel characteristics, protein structure, and digestive properties

To investigate the effects of beta-carotene on the gelling and digestion properties of surimi gels and the underlying molecular mechanisms, the gel properties, moisture distribution, rheological properties, secondary structure and microstructure were determined at different beta-carotene concentrations (0 % similar to 0.1 %). The results indicated that beta-carotene levels from 0.02 % to 0.06 % were positively correlated with gel properties, and the storage modulus (G') gradually increased during heating. This was attributed primarily to the conversion of alpha-helix to beta-sheet structures and the intensification of hydrophobic interactions, resulting in a more compact microstructure. Most importantly, at an additional level of 0.06 %, the digestibility did not significantly decrease with increasing gel properties. Moreover, the antioxidant activity of the hybrid gels subjected to gastrointestinal digestion was also enhanced. The present study provides a theoretical foundation for incorporating beta-carotene into surimi which will provide more nutritious products.