Comprehensive cryoprotection analysis of stachyose in minced lamb: Insights into ice crystallization, structural...

Cryoprotective effect and potential mechanism of stachyose on minced lamb was investigated at concentrations of 0 %, 1 %, 3 % and 5 % during 8-week of frozen storage. Results demonstrated that stachyose effectively inhibited ice-crystal formation and growth by depressing the freezing point and rising unfreezable water content, thereby maintaining the microstructure integrity of frozen minced lamb. Abundant hydroxyl groups introduced by stachyose at higher concentrations (3-5 %) preserved myofibrillar protein (MP) conformations under combined oxidative and cryo-mechanical stresses, as evidenced by stable α-helix content and fluorescence intensity. These mechanisms retarded the exposure of hydrophobic groups and decline in solubility, weakening migration activity of moisture within muscle tissues and reducing thawing loss by 25.50-33.64 % after 8-week frozen storage. Concurrently, nearly fresh quality were sustained by stachyose, including water-holding capacity (WHC), texture, color, and TBARS values. Severe MP aggregation during late storage appeared in the minced lamb containing 1 % stachyose, leading to its paradoxical hydration capacity compared to controls. Conclusively, stachyose at appropriate concentrations imparted superior cryoprotective effects in minced lamb, providing critical insights for optimizing the frozen preservation of gelatinous meat products.