Cereal Chem 56:417 - 418. | VIEW
Phase Equilibria in the Aqueous System of Wheat Gluten Lipids and in the Aqueous Salt System of Wheat Lipids.
T. L.-G. Carlson, K. Larsson, Y. Miezis, and S. Poovarodom. Copyright 1979 by the American Association of Cereal Chemists, Inc.
The aqueous system of gluten lipids was studied for comparison with the wheat lipid-water system. Phase equilibria were determined and were illustrated in the form of a ternary system: nonpopular lipids/water/polar lipids. The structures of the phases were characterized by x-ray diffraction. Besides water and the nonpolar oil phase, three aqueous phases were observed. The lamellar phase and the reversed hexagonal liquid-crystalline phase were frequently observed in aqueous systems of polar lipids. A third liquid phase containing about 50-80% (w/w) water is analogous to the so-called L2-phase in simple amphiphile-water systems. The water system of wheat lipids is the first system of biological origin found to exhibit this phase. The functionality of the different phases with regard to baking is discussed on the basis of the phase properties. The physical behavior of extracted wheat lipids in the presence of a salt solution corresponding to that in a dough (0.260M NaCl, 0.070M KCl, 0.016M MgCl2, and 0.004M CaCl2) also was analyzed and related to phase equilibria and to corresponding structures in the aqueous system of wheat lipids. The degree of solubilization of nonpolar lipids in the lipid-water phases was substantially reduced when salt was present, and the phase euqilibria involving the L2-phase was different.