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Updated: Mar 18, 2026

Characterizing Individual Protein Aggregates by Infrared Nanospectroscopy and Atomic Force Microscopy
Published on: September 12, 2019
Analysis of Aggregate Structure in Food Protein Gels with the Concept of Fractal
T Hagiwara1, H Kumagai1, T Matsunaga1
1a Department of Applied Biological Chemistry, Division of Agriculture and Agricultural Life Sciences , The University of Tokyo , 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113 , Japan.
Abstract:
The fractal structure of the aggregates in food protein gels was analyzed. Three kinds of food protein gels were prepared: (1) β-lactoglobulin (β-LG) gel; (2) 11S soybean globulin gel; and (3) caseinate gel. From the concentration dependence of the gel elasticity, the fractal dimensions Df of the aggregates in the gels were evaluated, according to the theory of Shih et al. These gels showed the weak-link behavior described in the theory of Shih et al The values obtained for Df were 2.6-2.7, which were larger than those predicted by the cluster-cluster aggregation model for a dilute system. In addition, for the β-LG gels, the fractal dimension was also evaluated from the analysis of the gel image obtained with a confocal scanning laser microscopy, the value being close to that evaluated from the concentration dependence of the gel elasticity. These results indicate that the elastic behavior of the aggregate gels is a reflection of fractal structure of the aggregates in the gels.
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