Effect of ice glazing with chitosan on the quality and myofibrillar protein structure of fish balls induced by freeze-thaw cycles

The protective effect of ice glazing with 1.5% chitosan (CH) during the freeze-thaw (F-T) cycles on the quality and myofibrillar protein (MP) structure of fish balls was investigated. The results showed that the F-T cycles led to a significant increase in the amount of frost generation (from 0.34% to 13.57%) and ice crystal diameter (from 15.78 to 37.83 μm) on the surface of frozen fish balls. In addition, the quality of fish ball was significantly decreased and the structure of MP was damaged during F-T cycles (P < 0.05). Ice-glazing with CH decreased the thawing loss, cooking loss, and centrifugal loss of fish balls by 36.10%, 33.18%, and 32.11%, respectively, compared to control group. Moreover, ice-glazing with CH can maintain the MP structure of fish balls during F-T cycles. Compared with the control group, the surface hydrophobicity of CH ice-glazed samples was reduced by 35.78%, the content of free amino acids was increased by 24.86%. It can be concluded that ice glazing with CH is effective to inhibit the deterioration of quality and MP structure of fish balls.