Cryoprotection of Tremella polysaccharides in silver carp myofibrillar protein: stability improvement against...

Myofibrillar proteins of silver carp are susceptible to freezing denaturation, significantly degrading surimi quality. Tremella polysaccharide (TP), a natural edible mushroom polysaccharide, offers potential cryoprotective value and can inhibit this deterioration. The aim of this study was to investigate the cryoprotective effect of TP on the myofibrillar protein of silver carp.

Tremella polysaccharide effectively mitigated protein aggregation and freeze-induced denaturation. Specifically, 2.0% TP enhanced freeze-thawed protein solubility by 107.23%, reduced turbidity by 30.83%, and decreased the carbonyl content by 41.74%. It also inhibited freeze-induced protein degradation and retarded the loss of α-helix structure, with 2.0% TP increasing α-helix content by 41.83% after freeze-thaw cycles. Observations of protein freezing characteristics revealed that TP shortened the passage time through the maximum ice crystal formation zone and reduced ice crystal size. Molecular docking and dynamics simulations demonstrated that TP interacted with myosin amino acid residues with multiple hydrogen bonds, electrostatic interactions, van der Waals forces, and weak alkyl hydrophobic interactions, forming stable complexes and preserving protein structural integrity. The study found that TP mainly exerted cryoprotective properties by altering water behavior (reducing free water and weakening water flow), modifying ice crystals (inhibiting ice crystal formation and reducing ice crystal size), and stabilizing protein structure (multiple non-covalent interactions synergistically maintaining system stability).

Tremella polysaccharide exhibits excellent cryoprotective effects. This study provides a theoretical basis for developing edible mushroom polysaccharides as novel cryoprotectants. © 2026 Society of Chemical Industry.