THE PROTEINS OF WASHED, MINCED FISH MUSCLE HAVE SIGNIFICANT SOLUBILITY IN WATER

After washing the minced muscle tissue of 5 species of white-fleshed fish twice with water and a third time with 0.15% (26 mM) NaCl solution, a considerable, portion of the remaining protein was soluble when extracted with water at a 1:20 ratio. The amount of protein extracted was 20–36% of the protein extracted by buffered 1 M Lid solution, a good protein extractant. This amount of protein indicates that the extracted proteins were primarily myofibrillar. When soluble protein was plotted versus the logarithm of the NaCl concentration in the extracting solution, an inverse linear relationship was observed. The moisture content of the fish paste was related linearly to the log of the water-soluble protein with a correlation coefficient of 0.945. The solubility of the proteins of washed, minced Atlantic mackerel was much less than that of the five white-fleshed species tested.