Tapioca Starch Improves the Quality of <em>Virgatus nemipterus</em> Surimi Gel by Enhancing the Molecular Interaction in the Gel System

Abstract

The gel prepared by Nemipterus virgatus (N. virgatus) surimi alone still has some defects in texture and taste. Complexing with polysaccharides is an efficient strategy to enhance the gel properties. The main objective of the study was to analyze the relationship between the gel quality and molecular interaction of N. virgatus surimi gel after complexing with tapioca starch. The results make clear that the gel strength, hardness, and chewiness of surimi gel were increased by molecular interaction with tapioca starch. At the appropriate addition amount (12%, w/w), the surimi gel had excellent gel strength (17.48 N), water holding capacity (WHC) (89.01%), lower cooking loss rate (CLR) (0.95%), and shorted T2 relaxation time. Microstructure analysis indicated that the addition of tapioca starch made the surimi gel evenly distributed in the gel network structure, resulting in a significant reduction in cavities diameter, and the minimum diameter could be reduced to 20.33 &amp;mu;m. In addition, tapioca starch enhanced the hydrogen bond and hydrophobic interaction in the gel system and promoted the transformation of &amp;alpha;-helix to &amp;beta;-sheet (P&amp;amp;lt;0.05). Correlation analysis showed that the increased physicochemical properties of surimi gel was closely related to the enhanced non-covalent interactions. In conclusion, the non-covalent complexation with tapioca starch is an efficient strategy to enhance the gel quality of surimi gel.

Effect of κ‐carrageenan on the physicochemical and structural characteristics of ready‐to‐eat Antarctic Krill surimi gel

“…At low additions, κ‐carrageenan mainly plays a role in water absorption and filler, and the decrease of hydrophobic interaction might relate to the reduction of cooking loss. However, at higher additions (4% and 5% groups), the hydroxyl groups in κ‐carrageenan cross‐connected with hydrophobic sites and other residues in myofibrillar protein molecules as fillers, increasing hydrophobic interactions (Huang et al ., 2024). Furthermore, the increase of disulfide bonds in 4% and 5% groups may also be due to the interaction between κ‐carrageenan and protein molecules, which promotes the exposure and oxidation of internal sulfhydryl groups.…”

“…4c). Therefore, it can be speculated that the high‐temperature and high‐pressure condition led to the opening and recombination of the original gel network, especially promote the further formation of hydrogen bonds in κ‐carrageenan, thus improving the texture of RTE AKSG to a certain extent (Huang et al ., 2024). Meanwhile, no significant difference was found between the ionic bond content of RTE AKSG, except for the control group, proving that κ‐carrageenan had no significant effect on ion action in RTE AKSG.…”