Abstract: The effect of storage temperature on the rheological properties, water-holding capacity (WHC) and water distribution of chicken breast myofibrillar protein gel was investigated. Chicken breast was stored at refrigeration (4 ℃) and freezing-point temperature (?0.7 ℃). Gel strength was measured by a dynamic rheometer, WHC was determined by centrifugation, and the change of moisture status was analyzed by using low field nuclear magnetic resonance (LF-NMR). The results showed that with increasing storage time, the gel strength and WHC of chicken myofibrillar proteins displayed a declining trend for both storage temperatures, but significantly higher values of the parameters were achieved during freezing-point storage (P < 0.05). LF-NMR results indicated that the decreased proportion of immobilized water and the increased proportion of free water were related to the reduction in WHC, and more significant changes in the proportions of immobilized water and free water ratio were found during freezing-point storage (P < 0.05). Therefore, the gel strength and WHC of heat-induced chicken myofibrillar protein gels were better maintained during freezing-point storage, thereby maintaining better quality.

Key words: chicken breast, myofibrillar protein, rheology, low field nuclear magnetic resonance (LF-NMR)