Abstract: The marbling in pig longissimus dorsi cross-section between the 5th and 6th ribs was evaluated by scoring. Along with this, the relationship between marbling score and gel properties of pig longissimus dorsi under varying ionic strength and cooling methods was addressed. longissimus dorsi muscles between the 5th and 6th ribs could be divided into 3 grades by marbling score. Various marbling grades of longissimus dorsi muscles had better gel properties at 0.60 mol/L NaCl than at 0.45 mol/L NaCl (P＜0.05). Significant differences in gel water-holding capacity (WHC) (P＜0.01) and gel strength (P＜0.05) were found among various marbling grades under the conditions of 0.60 mol/L NaCl and the same cooling methods, while gel elasticity did not show significance (P＞0.05). Gel properties of grade 3 were the best under 0.60 mol/L NaCl and 10 ℃ cooling. In addition, marbling grades had significantly positive correlation with gel WHC (P＜0.05), and the correlations with protein solubility and gel strength reached an extremely significantly positive level  (P＜0.01). Higher marbling grade of longissimus dorsi muscle had improved gel properties.

Key words: marbling, gel properties, ionic strength, cooling method