Cereal Chem 48:182 - 190. | VIEW
Preparation and Characterization of Coconut Protein Isolates.
A. S. Samson S. J., C. M. Cater, and K. F. Mattil. Copyright 1971 by the American Association of Cereal Chemists, Inc.
The following protein fractions have been separated from dried, defatted fresh coconut meats: 1) soluble at pH 2, precipitated at pH 3.9; 2) soluble at pH 8, precipitated at pH 3.9; 3) soluble at pH 10.5, precipitated at pH 3.9; 4) extracted sequentially at pH 10.5 from pH 8 residue and subsequently precipitated at pH 3.9; 5) extracted at pH 7 by 1.0M NaCl and precipitated at pH 2; 6) soluble in water at pH 7.0; and 7) proteins remaining in solution at pH 3.9. The recoveries were 1) 45 to 57%; 2) 39 to 53%; 3) 31 to 35%; 4) 14 to 19%; 5) 48 to 54%; 6) 9 to 11%; and 7) 3 to 6%. Hydrochloric was the most efficient precipitating acid of those tested, including sulfuric, phosphoric, acetic, and nitric. Each of the precipitated isolates was dried by lyophilization. While all of the isolates were quite soluble at pH 2, there were substantial differences in solubilities at pH 7, 8, and 10. All isolates were quite insoluble from pH 4 to 6. The amino acid composition of most of the isolates did not vary markedly from that of the original meal. The water-solubles were somewhat higher in lysine, arginine, and glutamic acid and lower in the remaining amino acids. The isolate extracted sequentially at pH 10.5 from pH 8 residue was lower in lysine and glutamic acid.