Abstract
Limited hydrolysis (4% degree of hydrolysis) of extruded-expelled soy flour protein (protein dispersibility index=21) that was poor in solubility and other functional properties was evaluated at pilot-plant scale (5 kg of flour) with two endopeptidases and one exopeptidase. Some hydrolysates were merely spray-dried whereas others were jet-cooked at 104°C for 19 s before spray-drying. Solubility, emulsification capacity and stability, foaming capacity and stability, apparent viscosity, and sensory attributes were then characterized. The type of protease used and hydrothermal cooking affected functional and sensory properties. Protein solubility modestly increased with hydrolysis and jet cooking, but emulsification capacity decreased on hydrolysis and was not restored with hydrothermal cooking. Emulsion stability improved in the endopeptidase hydrolysates, but not in the exopeptidase hydrolysates. The foaming capacities of the hydrolysates for both types of enzymes were better than for the unhydrolyzed control. Highly stable foams were obtained after hydrolyzing with exopeptidase and hydrothermal cooking. Ten percent protein hydrolysate dispersions showed large losses in consistency coefficient apparent viscosity, which increased significantly with hydrothermal cooking only for the unhydrolyzed control. Difference-from-control sensory evaluation indicated that both jet-cooked and non-jet-cooked enzyme hydrolysates were different from unhydrolyzed controls.
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Panyam, D., and A. Kilara. Enhancing the Functionality of Food Proteins by Enzymatic Modification. Trends Food Sci. Technol. 7:120–125 (1996).
Surowka, K., D. Zmudzinski, and J. Surowka, Enzymaic, Modification of Extruded Soy Protein Concentrates as a Method of Obtaining New Functional Food Components. —Ibid. 15:153–160 (2004).
Kim, S.K., P.S. Park, and K.C. Rhee. Functional Properties of Proteolytic Enzyme Modified Soy Protein Isolate. J. Agric. Food Chem. 38:651–656 (1990).
Achouri, A., W. Zhang, and S. Xu, Enzymatic Hydrolysis of Soy Protein and Effect of Succinylation on the Functional Properties of Resulting Protein Hydrolysates, Food Res. Int. 31:617–623 (1998).
Surowka, K., D. Zmudzinski, M. Fik, R. Macura, and W. Lasocha, New Protein Preparations from Soy Flour Obtained by Limited Enzymic Hydrolysis of Extrudates, Innov. Food Sci. Emer. Technol. 5:225–234 (2004).
Hrckova, M., M. Rusnakova, and J. Zemanovic, Enzymatic Hydrolysis of Defatted Soy Flour by Three Different Proteases and Their Effect on the Functional Properties of Resulting Protein Hydrolysates, Czech J. Food Sci. 20:7–14 (2002).
Calderon-de-la Barca, A.M., R.A. Ruiz-Salazar, and M.E. Jara-Maarini, Enzymatic Hydrolysis and Synthesis of Soy Protein to Improve Its Amino Acid Composition and Functional Properties, J. Food Sci. 65:246–253 (2000).
Nelson, L.L., W.B. Wijeratne, W.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).
Crowe, T.W., L.A. Johnson, and T. Wang, Characterization of Extruded-Expelled Soybean Flours, —Ibid. 78:775–779 (2001).
Wang, T., and L.A. Johnson, Survey of Soybean Oil and Meal Qualities Produced by Different Processes, —Ibid. 78:311–318 (2001).
Heywood, A.A., D.J. Myers, T.B. Bailey, and L.A. Johnson, Functional Properties of Extruded-Expelled Soybean Flours from Value-Enhanced Soybeans, —Ibid. 79:699–702 (2002).
Heywood, A.A., D.J. Myers, T.B. Bailey, and L.A. Johnson. Functional Properties of Low-Fat Soy Flour Produced by an Extrusion-Expelling System, —Ibid. 79:1249–1253 (2002).
Wang, H., L.A. Johnson, and T. Wang, Preparation of Soy Protein Concentrate and Isolate from Extruded-Expelled Soybean Meals, —Ibid. 81:713–717 (2004).
Wang, H., T. Wang, and L.A. Johnson, Refunctionalization of Extruded-Expelled Soybean Meals, —Ibid. 81:789–794 (2004).
Adler-Nissen, J., Enzymic Hydrolysis of Food Proteins, Elsevier Ltd., New York, 1986, pp 116–125.
Jung, S., P.A. Murphy, and L.A. Johnson, Physicochemical and Functional Properties of Soy Protein Substrates Modified by Low Levels of Protease Hydrolysis, J. Food Sci. 70:180–186 (2005).
Rickert, D., L.A. Johnson, and P.A. Murphy, Functional Properties of Improved Glycinin and β-Conglycinin Fractions, —Ibid. 69:303–311 (2004).
Meilgaard, M., G.V. Civille, and B.T. Carr, Sensory Evaluation Techniques. Vol. II, CRC Press, Boca Raton, FL 1987.
Plietz, P., B. Drescher, and G. Damaschun, Relationship Between the Amino Acid Sequence and the Domain Structure of the Subunits of the 11S Seed Globulins Int. J. Biol. Macromol. 9:161–165 (1987).
Wang, C., and L.A. Johnson, Functional Properties of Hydrothermally Cooked Soy Protein Products, J. Am. Oil Chem. Soc. 78:189–195 (2001).
Mahmoud, M.I., Physicochemical and Functional Properties of Protein Hydrolysates in Nutritional, Products, Food Technol. 48:89–95 (1994).
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Lamsal, B.P., Reitmeier, C., Murphy, P.A. et al. Enzymatic hydrolysis of extruded-expelled soy flour and resulting functional properties. J Amer Oil Chem Soc 83, 731–737 (2006). https://doi.org/10.1007/s11746-006-5031-0
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DOI: https://doi.org/10.1007/s11746-006-5031-0