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 β-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 β-carotene concentrations (0 % ∼ 0.1 %). The results indicated that β-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 α-helix to β-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 β-carotene into surimi which will provide more nutritious products.