Investigating the microstructural and cryoprotective superiority of fructooligosaccharides and sugar alcohols for maintaining peeled white shrimp (Litopenaeus vannamei) quality after repeated freeze-thaw cycles

For the seafood industry, a significant consideration is the reduction in the use of phosphate and NaCl in frozen shrimp. This study, therefore, investigated the impact of various cryoprotectant treatments on the physicochemical, structural, and visual quality of shrimp after repeated freeze-thaw cycles. Shrimp samples were subjected to 1, 3, and 5 freeze-thaw cycles and treated with different cryoprotectants, including sorbitol, xylitol, fructooligosaccharides (FOS), trisodium citrate, and NaCl, compared to DI water (control). The quality parameters evaluated included thawing loss, water holding capacity, cooking yield and cooking loss, protein content, pH, lipid oxidation, texture, microstructure, and color parameters. The findings indicated that repeated freeze-thaw cycles significantly increased moisture and protein loss, weakened texture and color stability, and led to the disruption of muscle structure. Saccharide-based cryoprotectants, particularly FOS, effectively reduced quality deterioration by stabilizing muscle proteins, minimizing water release, limiting lipid oxidation, and preserving microstructure and pigment integrity. These results demonstrate that FOS offers promising cryoprotective benefits, with potential applications in clean-label seafood preservation and enhanced product stability during cold chain distribution.