QUANTIFICATION OF BEEF MYOFIBRILLAR PROTEINS BY SDS-PAGE

A semi-quantitative determination of beef myofibrillar proteins using sodium, dodecyl sulphate polyacrylamide gel electrophoresis is describ ed. Bovine serum albumin was used as internal standard. Results indica te a linear relationship between densitometric readings after staining with Coomassie brilliant blue R250 and protein content. Recoveries of four pure proteins, loaded within a range of 0.5-4 mug, were between 92 and 110%. Heating of beef myofibrillar protein samples during disso lution is shown to be unnecessary. The method allows the quantitative study of myofibrillar degradation during beef aging, without overlappi ng of troponin-T with tropomyosin bands.