2025 Volume 31 Issue 3 Pages 205-213
The aim of study is to clarify the effects of freezing and thawing on the drip loss and structural properties of surimi gels. The gel sample was subjected to repeated freeze-thaw cycles to measure drip loss, and the contents of free water, holding water, and bound water were determined. The results showed that rapid freezing with liquid nitrogen effectively reduced the free water content compared to slow freezing at -25°C. Infrared (IR) and small-angle X-ray scattering (SAXS) analyses of gels subjected to freezing and thawing were conducted. The IR analysis results revealed that although minimal changes in protein secondary structure were observed, the molecular network of water in the gel structure was altered. The SAXS results indicated changes in the nanoscale structure when gels were subjected to repeated freeze-thaw cycles. The study concluded that the main factors affecting the water-holding capacity during freeze-thaw cycling are changes in the water molecular state and water-solid interactions in the gel, rather than changes in the protein structure.
