46G-6 |
Comparison of water soluble and salt soluble protein fractions from chicken breast meat |
N. S. HETTIARACHCHY, R. Cai, and C. K. Yang. Dept. of Food Science, Univ. of Arkansas, Fayetteville, AR 72704 Sodium salts are important non-meat ingredients in improving flavor, texture and functionality of meat products. Since proteins are major chicken meat components, interactions among proteins, water and salts play a key role in determining the functionality of chicken meat products. Increase in solubility of meat proteins in the presence of salts may furnish additional functions for the products. It is, therefore, necessary to compare protein fractions soluble in water and salt solutions, which could provide useful information for meat processor. Our objective was to compare protein constituents of chicken breast protein fractions extracted using water and three sodium salt solutions. Three sodium salts were studied, including sodium chloride, sodium hexametaphosphate and sodium tripolyphosphate. Chicken proteins were extracted with water or salt solutions by blending, centrifugation, dialyzing, and freeze-drying. Protein content was determined using Kjeldahl method. Protein subunits were compared using gel electrophoresis. Kjeldahl determination indicated that protein fractions soluble in aqueous sodium chloride, sodium hexametaphosphate and sodium tripolyphosphate had a protein content of 91.7%, 91.4% and 90.7%, respectively, higher than did water soluble fractions (86%). Non-reduced SDS-gel electrophoresis with both water and salt fractions showed major bands at 30-66 kDa. Salt soluble fractions showed an additional major band at 95 kDa and several bands above 100 kDa. Reducing SDS-gel electrophoresis indicated that the salt soluble bands at 95 and above 100 kDa were converted to lower molecular weight subunits after treatment with reducing agent 2-mercaptoethanol, as did the major bands for water and salt soluble fractions. Our results suggest that all three sodium salts soluble fractions had protein components higher than 100 kDa, which may contribute to improved functional property since those components were not observed with water soluble fraction. These higher molecular weight components were susceptible to reducing agent treatment, suggesting they contain higher amounts of disulfide bonds.
Session 46G, Muscle Foods I
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