ABSTRACT
Detailed procedures for preparation of samples for the analysis of individ ual groups of food products are described in Volume II of the Official Meth ods o f Analysis ofAOAC International
4.2. SEPARATION OF PROTEIN FROM DIFFERENT FOOD MATRICES
4.2.1. PROTEIN EXTRACTION
4.2.1.1. General App
Native skeletal muscle proteins are generally classified, based on their sol ubility in aqueous solvents, into the following three basic groups:
(1) Sarcoplasmic proteins are soluble in solution of low salt concentration (/ < 0.1), but not in water, such as globulin X and water-soluble albumins such as myoglobin and the so-called myogen fraction including most gly colytic enzymes. They are most often extracted with solutions of phos phorus salts of ionic strength I = 0.05 (e.g., 15.5 mM Na2HP04 + 3.38 mM KH2P 0 4, pH 7.3) (Shibata, 1979). As these proteins have been some times extracted with pure water, the name “water-soluble proteins” has become common.
