Factors Affecting the Sodium Chloride Extractability of Muscle Proteins From Chicken Breast, Trout White and Lobster Tail Muscles

The amount of protein extracted from chicken breast muscle at low salt (0–50 mM NaCl) increased as the salt concentration of the extracting solutions increased. The addition of 10 mM sodium phosphate buffer pH 7 (Pi) caused a marked increase in protein extractability at all salt concentrations. A particular polypeptide chain of about 150,000 daltons appeared to be particularly sensitive to the extraction conditions. At high salt (0.6M NaCl, 50 mM sodium phosphate buffer pH 7.0) a second extraction still contained significant amounts of protein. The amount of protein extracted was maximized at a 1/20 dilution. On the other hand, the protein extract-ability of trout white muscle, showed a smaller Pi effect and very little dependence on low salt concentration. The protein extractability of lobster flexor muscle showed little change with either increased salt or Pi. For all three muscles extraction over time with either high or low salt remained essentially constant after the first day with the most protein being extracted from lobster muscle and the least from chicken muscle.