Cyclodextrin induces synergistic cryoprotection with carrageenan oligosaccharide against myofibrillar protein denaturation during fluctuated frozen storage.

High-performance saccharide-based cryoprotectants are gaining increasing attention for their application in frozen meat products. While various physiochemical and/or enzymatic approaches have been employed to enhance the cryoprotective efficacy of saccharides, potential synergistic effects between different saccharide candidates remain largely unexplored. This study, for the first time, demonstrates that the combinational use of β-cyclodextrin (CD) and carrageenan oligosaccharide (CGO) exhibit significant synergistic cryoprotective effects on surimi myofibrillar proteins (MP) during freeze-thaw cycles. At 1 wt% concentration, the CD-CGO complex exhibited significantly greater cryoprotective efficiency than the commercial surimi cryoprotectant (4 % sucrose with 4 % sorbitol). Specifically, the CD-CGO co-treatment mitigated surimi MP denaturation over six freeze-thaw cycles, as evidenced by increased solubility (2.17 times), Ca-ATPase activity (3.91 times), and sulfhydryl content (2.55 times), along with reduction in surface hydrophobicity (0.42 times). In addition, freezing-induced MP aggregation and conformational changes, e.g., α-helix loss and disulfide bond destabilization, were effectively inhibited. Consequently, MP treated with CD-CGO complex demonstrated more ordered microstructures, uniform water distribution, and significantly improved viscoelasticity and mechanical strengths. This study provides a novel synergistic paradigm to boost saccharide cryoprotection performance, which also exhibits the potentials to elevate the FT stability of MP gel products.