Fractal analysis of structure of beta-lactoglobulin preparations

Beta-lactoglobulin (beta-Lg) preparations obtained from whey retentate through (a) salting out at high NaCl concentration in a strongly acid medium (30% NaCl, pH 2.0), (b) alfa-lactalbumin (alfa-La) removal at mild conditions (55 degrees C/30 min, pH 3.9) and (c) alfa-La removal with 6% TCA solutions (20 degrees C/40 min) were characterized by high values (1.31 to 1.33) for fractal dimension (D(L)), indicating their developed surface. At the same time, a small differentiation between these values allows assuming that the methods of the protein isolation from whey retentate did not influence the surface development. High values for correlation coefficients indicated a great accuracy of the method used for the measurements of the protein particles.