Date: 09/03/2026

The sensory performance of meat products and plant-based analogues is directly related to the functional properties of the ingredients used in the formulation, including Textured Soy Protein (TSP).

Its adoption influences parameters such as texture, moisture retention, structural stability and perceived juiciness - attributes that enhance the sensory experience, contributing to greater consumer acceptance, processing yield and batch-to-batch standardization.

When the product undergoes thermal processing, this relationship becomes even more evident. The choice of protein source interferes with the formation of the structural matrix, determining how water and fat are distributed and retained throughout heating. As a result, variations in hydration capacity, protein network structuring and emulsion stability tend to translate into differences in firmness, cohesion, cooking loss and mouthfeel.

In this context, evaluating Textured Soy Protein requires an approach that considers its interaction with the food matrix and its effects on sensory quality indicators.

In this article, you will find:

How extrusion changes the structure of Textured Soy Protein

Textured Soy Protein is produced through extrusion, a process in which the raw material is simultaneously subjected to heat, pressure, temperature and mechanical shear. This combination promotes protein reorganization and generates the fibrous structure characteristic of the ingredient.

To understand what this means in practice, it is useful to examine the thermal behavior of soy proteins, as described by Petruccelli and Anon (1995) in the study Thermal Aggregation of Soy Protein Isolates. The authors demonstrated that when heated above 85 °C, proteins undergo denaturation, with exposure of hydrophobic regions and subsequent formation of stabilized aggregates through hydrophobic interactions and disulfide bonds.

Although the study was conducted with protein isolates, it clarifies how heat modifies protein organization, altering their ability to form more cohesive structures.

During extrusion, this phenomenon occurs under even more intense thermal and mechanical energy conditions. As the material exits the die under a pressure drop, it expands, forming a porous internal structure. This porosity influences the hydration capacity of the ingredient.

Therefore, extrusion modifies the physical architecture of soy protein, creating a matrix that tends to absorb and retain liquids after rehydration. This structural effect is one of the starting points for understanding its influence on texture and juiciness in thermally processed systems.

Water retention: evidence on hydration in soy derivatives

Water retention is a determining factor for maintaining juiciness and processing yield in products subjected to thermal processing. During heating, water loss is associated with shrinkage, texture changes and reduced perceived tenderness.

Seibel and Beléia (2009), in a study published in the Brazilian Journal of Food Technology, evaluated technological properties of soy derivatives and reported specific values for the water absorption index (WAI) of up to 8.4 g/g and swelling volume (SV) of up to 18 mL/g, depending on the fraction analyzed.

The water absorption index (WAI) indicates the amount of water retained per gram of ingredient after hydration. A value of 8.4 g/g means that 1 g of the material can retain up to 8.4 g of water under the experimental conditions described in the study. Swelling volume (SV), in turn, expresses the volumetric expansion resulting from this water incorporation.

These parameters were obtained under standardized laboratory conditions, allowing them to be used as a reference to evaluate hydration capacity. When related to the porous structure formed during extrusion, these results help explain how soy derivatives can contribute to greater water retention in processed systems.

Fat stability and emulsifying properties in soy-based systems

In addition to water retention, lipid phase stability also influences texture, cohesion and perceived tenderness. In emulsified products such as burgers, sausages or structured plant-based analogues, the homogeneous distribution of fat determines matrix integrity during heating.

The emulsifying properties of soy proteins were evaluated by Wang et al. (2006) in the study Whipping and Emulsifying Properties of Soybean Products. The authors observed that emulsifying capacity is related to protein solubility and the capacity of proteins to adsorb at the oil-water interface, forming stable interfacial films.

Partially denatured proteins exhibit exposed hydrophobic regions, which favor this interfacial interaction. At the same time, hydrophilic portions remain oriented toward the aqueous phase, promoting system stabilization. This behavior is characteristic of globular proteins subjected to controlled heating.

From a technological standpoint, efficient emulsification reduces phase separation, minimizes lipid exudation and contributes to a more uniform matrix after cooking. Balanced fat distribution directly impacts perceived juiciness and mouthfeel, particularly in products where fat plays both a structural and sensory role.

Thus, when analyzing the sensory performance of systems incorporating soy derivatives, water retention should be considered together with fat stability. Both mechanisms - hydration and emulsification - act in an integrated manner in defining final texture.

Gelation and protein network formation during heating

In food systems subjected to heat, protein gel formation is one of the central mechanisms in texture development. Gelation occurs when denatured proteins begin to interact with each other, forming a continuous three-dimensional network capable of entrapping water and fat.

The gelation properties of soy proteins were discussed by Renkema and van Vliet (2002) in the study Gelling Properties of Soy Proteins. The authors demonstrated that gel formation depends on protein concentration, pH and the intensity of thermal treatment. As temperature increases, denaturation occurs followed by controlled aggregation, resulting in a structured network that provides firmness to the system.

This behavior was also described by Petruccelli and Anon (1995), who observed that above approximately 85 °C, soy proteins form stabilized aggregates through hydrophobic interactions and disulfide bonds. These interactions are responsible for structural cohesion after heating.

From a technological standpoint, the formation of this network directly influences parameters such as firmness, elasticity and cutting resistance. The more organized and continuous the protein matrix, the lower the tendency for syneresis (water release) and the greater the structural stability of the product after cooking.

In meat products and plant-based analogues, gelation integrates with water retention and fat stability, consolidating the final structure of the food. Perceived texture - tenderness, cohesion and bite resistance - results from the simultaneous interaction of these physicochemical mechanisms.

Integrated impact on sensory performance

Structural reorganization during extrusion, water retention capacity and fat stability, together with protein network formation through gelation, are physicochemical mechanisms that do not act in isolation. In thermally processed systems, these phenomena occur simultaneously and determine final sensory quality.

Water retention, measured by indices such as the water absorption index (WAI) (up to 8.4 g/g, according to Seibel and Beléia, 2009), is related to moisture maintenance after heating. Products with higher retention capacity tend to exhibit lower cooking loss and greater perceived tenderness. Juiciness, in this context, is the result of water remaining within the structural matrix.

At the same time, fat stability - associated with the emulsifying capacity of soy proteins described by Wang et al. (2006) - influences lipid distribution within the matrix. A more stable emulsion reduces exudation and contributes to a creamy sensation and uniform mouthfeel.

Thermal gelation, as discussed by Renkema and van Vliet (2002) and Petruccelli and Anon (1995), consolidates this structure by forming a cohesive three-dimensional network. This network defines firmness, elasticity and cutting resistance, parameters that directly impact texture perception during mastication.

From a sensory standpoint, what the consumer perceives as “pleasant texture” or “good juiciness” results from the interaction between:

● Water retention within the structure;
● Lipid phase stability;
● Continuity of the protein network formed during heating.

When these elements are balanced, there is lower liquid release, reduced structural shrinkage and greater product integrity after cooking. Final sensory quality, therefore, can be understood as a macroscopic manifestation of the molecular and structural processes described in the scientific literature.

Use of MBRF Textured Soy Protein in processed systems

During product development, selecting a textured ingredient involves decisions related to particle size, hydration behavior and compatibility with the selected thermal regime. These variables directly influence the final structure of the matrix and system stability after cooking.

When analyzing a specific textured protein, these decisions depend on the processing characteristics applied to the raw material. Prior thermal treatment and extrusion conditions determine the structural organization of the ingredient and its functional response during rehydration and heating.

In the case of MBRF Ingredients Textured Soy Protein, the product is obtained from soybeans subjected to a specific thermal treatment followed by controlled extrusion. This process influences the formation of the fibrous structure and the stability of the ingredient throughout thermal processing. The brand’s portfolio includes different particle sizes, allowing adjustments according to the application.

In practice, improved sensory performance in meat products and plant-based analogues is associated with how the food matrix is structured and stabilized during processing. Textured Soy Protein influences this arrangement by affecting liquid retention, internal cohesion and behavior under heating.

Would you like to evaluate the use of Textured Soy Protein in your formulation?

Explore MBRF Ingredients solutions and contact our technical team to discuss specifications, particle size and application parameters according to your production process.