Abstract
Soy protein concentrates (SPC) and soy protein isolates (SPI) were produced from hexane-defatted soy white flakes and from two extruded-expelled (EE) soy protein meals with different degrees of protein denaturation. Processing characteristics, such as yield and protein content, and the key protein functional properties of the products were investigated. Both acid-and alcohol-washed SPC from the two EE meals had higher yields but lower protein contents than that from white flakes. Generally, SPC from an acid wash had much better functional properties than those from an alcohol wash. The SPI yield was highly proportional to the protein dispersibility index (PDI) of the starting material, so the EE meal with lower PDI had lower SPI recovery. The protein content in SPI prepared from EE meals was about 80%, which was lower than from white flakes. Nevertheless, SPI from EE meals showed functional properties similar to or better than those from white flakes. The low protein contents in SPC and SPI made from EE meals were mainly due to the presence of residual oil in the final products. SPI made from EE meals had higher concentration of glycinin relative to β-conglycinin than that from white flakes.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Campbell, M.F., C.W. Kraut, W.C. Yackel, and H.S. Yang, Soy Protein Concentrate, in New Protein Foods, Vol. 5: Seed Storage Proteins edited by A.M. Altschul and H.L. Wilcke, Academic Press, London, 1985, pp. 300–337.
Kolar, C.W., S.H. Rickert, C.D. Decker, F.H. Steinke, and R.J. Van-der Zanden, Isolated Soy Protein,, pp. 259–300.
Nelson, A.I., W.B. Wijeratne, S.W. Yeh, T.M. Wei, and L.S. Wei, Dry Extrusion as an Aid to Mechanical Expelling of Oil from Soybeans, J. Am. Oil Chem. Soc. 64:1341–1347 (1987).
Lusas, E.W., and K.C. Rhee, Soybean Protein Processing and Utilization, in Practical Handbook of Soybean Processing and Utilization, edited by D.R. Erickson, AOCS Press and the American Soybean Association, Champaign, 1995, pp. 117–160.
Berk, Z., Technology of Production of Edible Flours and Protein Products from Soybeans, Food and Agriculture Organization of the United Nations (FAO), Rome, 1992, pp. 73–96.
Corn Refiners Association (CRA), Standard Analytical Method of the Member Companies of Corn Refiners Association, Inc., CRA, Washington, DC, 1980, Method A-18.
Johnson, L.A., C.W. Deyoe, and W.J. Hoover, Yield and Quality of Soymilk Processed by Steam-Infusion Cooking, J. Food Sci. 46:239–243 (1981).
Official Methods and Recommended Practices of the AOCS, 5th edn., AOCS Press, Champaign, 1997, Method Ba 10-65.
Swift, C.E., C. Lockett, and A.J. Fryer, Comminuted Meat Emulsions: The Capacity of Meat for Emulsifying Fat, Food Technol. 15:468–472 (1961).
Wilde, P.J., and D.C. Clark, Foaming Formation and Stability, in Methods of Testing Protein Functionality, 1st edn., edited by G.M. Hall, Chapman & Hall, London, 1996, pp. 110–152.
Official Methods of AOAC International, 17th edn., AOAC International, Gaithersburg, MD, 2000, AOAC Official Method 945.02.
Ibid., Official Methods of AOAC International, 17th edn., AOAC International, Gaithersburg, MD, 2000, AOAC Official Method 962.09.
Dubois, M., K.A. Gilles, J.K. Hamilton, P.A. Rebers, and F. Smith, Colorimetric Method for the Determination of Sugars and Related Substances, Anal. Chem. 28:350–356 (1956).
Statistical Analysis System, SAS Institute, Cary, NC, 1999–2001.
Bian, Y., D.J. Myers, K. Dias, M.A. Lihono, S. Wu, and P.A. Murphy, Functional Properties of Soy Protein Fractions Produced Using a Pilot Plant-Scale Process, J. Am. Oil Chem. Soc. 80:545–549 (2003).
Rickert, D.A., L.A. Johnson, and P.A. Murphy, Functional Properties of Improved Glycinin and Beta-Conglycinin Fractions, J. Food Sci. 68:303–311 (2004).
Author information
Authors and Affiliations
Corresponding author
About this article
Cite this article
Wang, H., Johnson, L.A. & Wang, T. Preparation of soy protein concentrate and isolate from extruded-expelled soybean meals. J Amer Oil Chem Soc 81, 713–717 (2004). https://doi.org/10.1007/s11746-004-966-8
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/s11746-004-966-8