Preparation of soy protein-based food gels and control of fibrous structure and rheological property by freezing

The continued development and increasing demand of the fast-growing market for meat alternatives will provide sufficient possibilities for food scientists and entrepreneurs to develop new technologies. The texture-related sensory qualities of meat analogues are the focus of product development and applied research. In this study, the freezing process was used to control the fibrous structure (i.e., anisotropic layered porous structure) and rheological property of soy protein-based food gels compared to animal meat. Soybean flour and two types of soy protein isolate powders were studied in terms of their ability to produce meat-like structures and rheological properties. It was found that certain combinations of the isolate powders and freezing conditions can produce multi-layered structures in food protein gels. Moreover, soybean flour at a 10% solid content formulation resulted in the formation of the densest layers layered with a relatively porous and anisotropic structure that achieved a breaking strength equivalent to that of actual meat. The growth of ice crystals in the protein gel, which is key in mimicking actual meat structures, was significantly influenced by the gelling ability of the samples. Soybean flour, which has a low gelling ability, is a good candidate for structuring soy protein-based food gels by freezing.