Effects of Freezing and Thawing Cycles on Quality and Processing Characteristics of Surimi

In order to study the effect of freeze-thaw cycle on quality of surimi under different low temperature conditions, the prepared surimi samples were divided into 3 groups and placed in the refrigerator at 4, −18, −35 ℃, respectively. Five repeated freeze-thaw cycles were simulated. Different indexes, such as rheological characteristics, gel properties, water changes (low field nuclear magnetic resonance (LF-NMR), freezing loss, thawing loss, cooking loss rate, water holding capacity (WHC)), texture characteristic, were analyzed, which also combined with the microstructure observation, so as to assess storage temperature influence on the quality of minced fish during freeze-thaw cycles comprehensively. The results showed that the storage temperature and freezing-thawing cycle were important factors affecting the quality of surimi. The lower the storage temperature was, the less the quality of surimi changed. With the increase of the freezing-thawing cycle, the viscosity of surimi gel decreased, G' and G" decreased, and tanδ increased, and the hardness, chewiness, gel strength decreased first and then increased. The freezing loss and thawing loss were 2.18% and 22.87%, 2.38% and 10.20% at −18 ℃ and −35 ℃ for 5 cycles, respectively. The WHC of surimi decreased from 80.04% to 73.51% and 75.33%, respectively. The results of this study can provide theoretical reference for quality maintenance of surimi and its gel during circulation.