Abstract
Effects of drying methods on hydrophobicity, solubility, water hydration capacity, viscosity, and adhesive strength of soy protein isolates treated with Na2SO3 (disulfide bond-cleaving agent) were investigated. Treatment with 0.1 M Na2SO3 resulted in 28% decrease in disulfide linkages in soy proteins. While hydrophobicity and solubility increased, waterholding capacity of soy proteins decreased due to the treatment. Spray-dried product had higher hydrophobicity, solubility, water hydration capacity, and viscosity compared to freeze-dried product. Adhesive strength on wood increased due to modification; however, the drying process had no significant effect on this property. Viscosities of spray-dried product, freeze-dried product, and unmodified soy proteins were 2,200, 100, and 240 cP, respectively. Fluorescence spectra of spray-dried and freezedried products indicated a partial folding of molecules around tryptophan. High-performance liquid chromatographic elution profiles showed no significant differences in molecular sizes of unfolded molecules of spray-dried and freeze-dried proteins.
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Kalapathy, U., Hettiarachchy, N.S. & Rhee, K.C. Effect of drying methods on molecular properties and functionalities of disulfide bond-cleaved soy proteins. J Amer Oil Chem Soc 74, 195–199 (1997). https://doi.org/10.1007/s11746-997-0123-z
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DOI: https://doi.org/10.1007/s11746-997-0123-z