The role of water and oil migration in juiciness loss of stuffed fish ball with the fillings of pig fat/meat as affected by freeze-thaw cycles and cooking process

Abstract

The present study sought to investigate the effects of freeze-thaw (F-T) cycles and cooking process on the quality attributes of the stuffed fish balls to address its juiciness loss in terms of water and oil migration and microstructural changes. The results showed no significant changes in water and oil migration from the fillings to the outer surimi gel during the F-T cycles, while the water holding capacity decreased significantly and thaw loss increased with the increase of F-T cycles. The sectional observation revealed that after F-T cycles treatment, cooking caused a significant decrease in the moisture content of the fillings and oil-water migration from the fillings to the outer surimi gel to different extents. However, oil migration was less than water migration, suggesting that water migration played a major role in juiciness loss. Additionally, the low field nuclear magnetic resonance and microstructure analysis results showed that the ice crystals sizes and water mobility increased with multiple F-T cycles treatments. Compared with the F-T period, the water loss in the fillings of the stuffed fish ball subjected to F-T cycles was significantly higher during the cooking process, resulting in less juiciness.