Abstract:To study the effect of different refrigerated treatment methods on the quality change and endogenous enzyme activity of big-eye tuna(Thunnus obesus). Samples were stored under different refrigerated conditions (refrigerated storage (CK), crushed ice (CI) and slurry ice (SI)), the physicochemical (texture profile analysis (TPA), electrical conductivity and total volatile base-Nitrogen(TVB-N)), microbiological (Total viable counts), ATP-related compounds and enzyme activities (Adenosine deaminase (ADA) and Acid phosphatase (ACP)) indexes were measured respectively. The water mobility was evaluated by Low-field nuclear magnetic resonance (LF-NMR). The results showed that when compared with other groups, samples in SI could control the increase of electrical conductivity, TVB-N value, TVC and Hx contents. The hardness, springiness, chewiness, ATP and IMP content also declined slowly. The values of K, H, Ki were lower than other groups and Fr value showed a more gentle downward trend. The activities of ACP and ADA showed a upward trend in the later of storage, which could be restrained by SI. The activity of ACP and TVC had a certain correlation. The decrease of T22 and the increase of T23 indicated that water content in myofibrils was lost and the quality of big-eye tuna was deteriorated. Therefore, SI storage could slow down the degradation of ATP and quality deterioration in big-eye tuna by controlling the activity of endogenous enzyme and microbial growth.