Some Chemical and Nutritional Properties of Feather Protein Isolates Containing Varying Half-Cystine Levels

  • John P. Cherry
  • Kay H. McWatters
  • Josephine Miller
  • A. Lorne Shewfelt
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 86)


Feather (keratinous) protein isolates containing 2.8 and 7.2% half-cystine were prepared. Solubility of the former increased to 100% between pH 6 and 12, whereas, that of the latter reached only 2.5% at pH 12. Tests showed that mixtures of sodium dodecyl sulfate and 2-mercaptoethanol were needed to completely solubilize the high half-cystine protein, and that sodium dodecyl sulfate alone or in combination with urea and/or 2-mercaptoethanol increased solubilization of the low half-cystine product. The rates of these reactions are further increased by heat. Dry heat denatured the low half-cystine isolate more readily than the high half-cystine product; moist heat denatured both at a similar rate. Gel electrophoretic properties were unique for each keratinous product. Only the low half-cystine isolate had desirable functional properties in that it formed thick, viscous mayonnaise-like emulsions and desirable foams. Functional properties of this isolate were improved dramatically by adjusting the pH from 5.0 to 8.2 or by a two-step change from pH 5.0 to 4.0 to 8.2. Apparent nitrogen digestibility of the two keratinous isolates was greater than 90% as measured by rat growth and by pepsin-HC1 digestion.


Protein Isolate Nutritional Property Apparent Digestibility Peanut Meal Feather Meal 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Anonymous. (1976). Rice-textured soy blend has 18% protein content, PER of 2.5+. Food Proc. 37, 60–61.Google Scholar
  2. AOAC. (1970). “Official Methods of Analysis of The Association of Official Analytical Chemists,” Ed. Horwitz, W., Chichilo, P., and Reynolds, H. Assoc. Official Analytical Chemists, Washington, D. C.Google Scholar
  3. Baden, H. P., Goldsmith, L. A., and Fleming, B. (1973). The polypeptide composition of epidermal prekeratin. Biochim. et Biophys. Acta 317, 303–311.Google Scholar
  4. Balloun, S. L., and Khajareen, J. K. (1974). The effects of whey and yeast on digestibility of nutrients in feather meal. Poultry Sci. 53, 1084–1095.CrossRefGoogle Scholar
  5. Basha, S. M. M., and Cherry, J. P. (1976). Composition, solubility, and gel electrophoretic properties of proteins isolated from Florunner (Arachis hypogaea L.) peanut seeds. J. Agric. Food Chem. 24, 359–365.CrossRefGoogle Scholar
  6. Canalco Catalog. (1973). Disc electrophoresis. Canalco, Rockville, Md.Google Scholar
  7. Cherry, J. P., and Ory, R. L. (1973). Gel electrophoretic analyses of peanut proteins and enzymes. 2. Effects of thiol reagents and frozen storage. J. Agric. Food Chem. 21, 656–660.PubMedCrossRefGoogle Scholar
  8. Cherry, J. P., and Prescott, J. M. (1974). Electrophoretic evaluation of various procedures for solubilizing erythrocyte membranes. Proc. Soc. Exp. Biol. & Med. 147, 418–424.CrossRefGoogle Scholar
  9. Cherry, J. P., McWatters, K. H., and Holmes, M. R. (1975a). Effect of moist heat on solubility and structural components of peanut proteins. J. Food Sci. 40, 1199–1204.CrossRefGoogle Scholar
  10. Cherry, J. P., Young, C. T., and Shewfelt, A. L. (1975b). Characterization of protein isolates from keratinous material of poultry feathers. J. Food Sci. 40, 331–335.CrossRefGoogle Scholar
  11. Cherry, J. P., and McWatters, K. H. (1975). Solubility properties of proteins relative to environmental effects and moist heat treatment of full-fat peanuts. J. Food Sci. 40, 1257–1259.CrossRefGoogle Scholar
  12. Combs, G. E., Alsmeyer, W. L., and Wallace, H. D. (1958). Feather meal as a source of protein for growing finishing swine. J. Animal Sci. 17, 468–472.Google Scholar
  13. Courts, A. (1973). Recent advances in protein production. Process Biochem. 8 (2), 31–33.Google Scholar
  14. Durrum Model D-500 Amino Acid Analyzer Operation and Maintenance Manual. (1972). Durrum Instrument Corporation, Palo Alto, Calif.Google Scholar
  15. Fairbanks, G., Steck, T. L., and Wallach, D. F. H. (1973). Electrophoretic analysis of the major polypeptides of the human erythrocyte membrane. Biochemistry 10, 2606–2617.CrossRefGoogle Scholar
  16. Fraser, R. D. B., MacRae, T. P., and Rogers, G. E. (1972). “Keratins, Their Composition, Structure and Biosynthesis.” Charles C. Thomas, Springfield, Illinois.Google Scholar
  17. Gardner, H. K., Hron, R. J., and Vix, H. E. L. (1976). Removal of pigment glands ( Gossypol) from cottonseed. Cereal Chem. 53, 549–560.Google Scholar
  18. Goodwin, W. D. (1973). Nutrient protein from keratinaceous material by extraction with dimmethylformamide. U. S. Patent 3,773, 745.Google Scholar
  19. Graham, G. G., and Baertl, J. M. (1974). Nutritional effectiveness of soy cereal foods in undernourished infants. J. Amer. Oil Chem. Soc. 51, 152A - 155A.CrossRefGoogle Scholar
  20. Greenwood, B. D., and Speakman, P. T. (1964). Use of proteolytic enzymes in structural investigations of wool keratin. Nature 204, 144–146.CrossRefGoogle Scholar
  21. Harrap, B. S., and Woods, E. F. (1964a). Soluble derivatives of feather keratin. L. Isolation, fractionation and amino acid composition. Biochem. J. 92, 8–18.Google Scholar
  22. Harrap, B. S., and Woods, E. F. (1964b). Soluble derivatives of feather keratin. 2. Molecular weight and conformation. Biochem. J. 92, 19–26.Google Scholar
  23. Haurowitz, F. (1963). Structural proteins (scleroproteins and the muscle proteins)i Chapter IX in “The Chemistry and Function of Proteins.” Academic Press, New York, N. Y.Google Scholar
  24. Hollo, J., and Koch, L. (1970). Protein from green matter. Process Biochem. 5 (10), 37–39.Google Scholar
  25. Horan, F. E. (1973). Wheat-soy blends. High quality protein products. Cereal Sci. Today 18, 11–14.Google Scholar
  26. Humphrey, A. E. (1970). Microbial protein from petroleum. Process Biochem. 5 (6), 19–22.Google Scholar
  27. Jones, C. B., and Mecham, D. K. (1943). The dispersion of keratins. II. Studies on the dispersion of keratins by reduction in neutral salt solutions of protein denaturants. Arch. Biochem. 3, 193–202.Google Scholar
  28. Kakade, M. L. (1974). Biochemical basis for the differences in plant protein utilization. J. Agric. Food Chem. 22, 550–555PubMedCrossRefGoogle Scholar
  29. Lowry, 0. H., Rosebrough, N. J., Farr, A. L., and Randall, R. J. (1951). Protein measurement with the Folin phenol reagent. J. Biol. Chem. 193, 265–275.Google Scholar
  30. McCasland, W. E., and Richardson, L. R. (1966). Methods for determining the nutritive value of feather meals. Poul. Sci 45, 1231–1236.Google Scholar
  31. McDonagh, J., Messel, H., McDonagh, R. P., Murano, G., and Blomback, B. (1972). Molecular weight analysis of fibrinogen and fibrin chains by an improved sodium dodecyl sulfate gel electrophoresis method. Biochim. Biophys. Acta 257, 135–142.Google Scholar
  32. McWatters, K. H., and Cherry, J. P. (1975). Functional properties of peanut paste as affected by moist heat treatment of full-fat peanuts. J. Food Sci. 40, 1205–1209.CrossRefGoogle Scholar
  33. McWatters, K. H., Cherry, J. P., and Holmes, M. R. (1976). Influence of suspension medium and pH on functional and protein properties of defatted peanut meal. J. Agric. Food Chem. 24: 517–523.Google Scholar
  34. Menefee, E. (1965). Cross linking in keratin. II. Theory for sulfur disproportionation after chain scission and crosslink cleavage. J. Appl. Polym. Sci. 9, 2829–2834.Google Scholar
  35. Moran, E. T., Summers, J. D., and Slinger, S. J. (1966). Keratin as a source of protein for the growing chick. 1. Amino acid imbalance as the cause for inferior performance of feather meal and the implication of disulfide bonding in raw feathers as the reason for poor digestibility. Poultry Sci. 45, 1257–1266.Google Scholar
  36. Moran, E. T., Pepper, W. F., and Summers, J. D. (1969). Processed feather and hog hair meals as sources of dietary protein for the laying hen with emphasis on their needs in meeting maintenance needs. Poultry Sci. 48, 1245–1251.CrossRefGoogle Scholar
  37. Morris, W. C., and Balloun, S. L. (1973a). Effect of processing methods on utilization of feather meal by broiler chicks. Poul. Sci. 52, 858–866.CrossRefGoogle Scholar
  38. Morris, W. C., and Balloun, S. L. (1973b). Evaluation of five differently processed feather meals by nitrogen retention, net protein values, xanthine dehydrogenase activity and chemical analysis. Poul. Sci. 52, 1075–1084.CrossRefGoogle Scholar
  39. O’Donnell, I. J., and Thompson, E. 0. P. (1964). Studies on reduced wool. IV. The isolation of a major component. Aust J. Biol. Sci. 17, 973–989.Google Scholar
  40. Rhee, K. C., Cater, C. M., and Mattil, K. F. (1973). Aqueous process for pilot plant-scale production of peanut protein concentrate. J. Food Sci. 38, 126–128.CrossRefGoogle Scholar
  41. Roach, D., and Gehrke, C. W. (1970). Hydrolysis of protein. J. Chrom. 52, 393–404.CrossRefGoogle Scholar
  42. Rogers, C. J., Coleman, E., Spino, D. F., Purcell, T. C., and Scarpino, P. V. (1972). Production of fungal protein from cellulose and waste cellulosics. Environ. Sci. Tech. 6, 715–719.Google Scholar
  43. Routh, J. I. (1942). Nutritional studies on powdered chicken feathers. J. Nutr. 24, 399–404.Google Scholar
  44. Shapiro, A. L., Vinuela, D., and Maizel, J. V., Jr. (1967). Molecular weight estimation of polypeptide chains by electrophoresis in SDS-polyacrylamide gels. Biochem. Biophys. Res. Comm. 28, 815–820.Google Scholar
  45. Spackman, D. H., Stein, W. H., and Moore, S. (1958). Automatic recording apparatus for use in the chromatography of amino acids. Anal. Chem. 30, 1190–1206.Google Scholar
  46. Ward, W. H., High, L. M., and Lundgren, H. P. (1946). Physicochemical characterization of dispersed chicken feather keratin. J. Polymer Res. 1, 22–36.Google Scholar
  47. Weisberg, S. M. (1972). Developing and marketing low-cost protein foods in developing countries. Food Tech. 26, 60–68.Google Scholar
  48. Wolf, W. J., and Cowan, J. C. (1971). Soybeans as a food source. CRC Critical Rev. Food Tech. 2, 81–158.Google Scholar
  49. Woodin, A. M. (1954). Molecular size, shape and aggregation of soluble feather keratin. Biochem. J. 57, 99–109.PubMedGoogle Scholar
  50. Woodin, A. M. (1956). Structure and composition of soluble feather keratin. Biochem. J. 63, 576–581.PubMedGoogle Scholar
  51. Woods, E. F. (1971). Chromatography of the soluble proteins from feathers. Comp. Biochem. Physiol. 39A, 325–331.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 1977

Authors and Affiliations

  • John P. Cherry
    • 1
  • Kay H. McWatters
    • 1
  • Josephine Miller
    • 1
  • A. Lorne Shewfelt
    • 1
  1. 1.Department of Food ScienceUniversity of Georgia College of Agriculture Experiment StationsExperimentUSA

Personalised recommendations