Relationship between soybean protein composition and breaking load of heat-induced gel prepared from acid-precipitated soybean flour.

To understand the effective soy protein composition for realizing appropriate meat substitute, we evaluated the contribution of four protein fractions separated from soybeans, two types of globulins and two types of lipophilic proteins, to textural properties of heat-induced gels prepared from an acid-precipitate of soybean flour (AP-SF). When we added these fractions sduring the preparation of AP-SF gels, which increased the protein content by 10%, the gel with 7S globulin displayed the highest breaking load (417.7 gf). With respect to combinatorial effects, the AP-SF gel that added with 5% 7S and 5% 11S globulin reached an even higher value (460.2 gf) than the value described above (417.7gf). To further support the contribution of fractions, we investigated the correlation between the content of these four protein fractions in soybean flour from different cultivars and the breaking load of the heat-induced gels. The breaking load shows a stronger correlation with the total amount of 7S and 11S (r = 0.86) than with 7S alone (r = 0.77), 11S alone (r = 0.70), or the total amount of acid-precipitated proteins (r = 0.80). Thorough this research, we obtained new findings suggesting a synergistic effect between both globulins. • A high concentrated protein gels as meat analogues was prepared from soybean flour. • The optimal heating temperature for the gel hardness was around 115 °C. • The synergistic effect of 7S and 11S globulins contributes to the gel hardness. • Lipophilic proteins are unlikely to contribute to the gel hardness. [ABSTRACT FROM AUTHOR]