Rheological properties of pea protein concentrate versus isolate suspension as influenced by different hydrocolloids in model food systems

Sammendrag

The choice of protein fraction and associated hydrocolloids in plant-based formulation for dairy or meat alternatives, can be challenged with the vast available ingredients on the market issued from different processing or extraction techniques. The aim of this research was to study 1. The influence of CaCl2 on the viscoelastic behavior of hydrocolloidal suspensions, 2. the differential impacts observed of pea protein concentrate (PPC) and protein isolate (PPI) in hydrocolloidal suspensions at a macroscopic level, and finally 3. the addition of texturized pea protein (TPP) in pea protein/hydrocolloid model mixtures. Shear strain elasticity of nine commercial hydrocolloids (Alginate, guar, gellan and xanthan gum, κ-carrageenan, methylcellulose, citrus peel and sugar beet pectin) were measured. The results suggest that Ca2+ acts as a crucial crosslinking agent for alginate and enhances the shear strain moduli through crosslinking with carboxyl groups, while impeding gellan gum matrix structure due to constrained acyl-network formation. Distinct behaviors were observed for PPC versus PPI suspension, with PPI exhibiting higher viscoelasticity compared to PPC, underscoring the impact of protein purity and properties influenced by method of isolation. This is especially pronounced when mixed with hydrocolloids. The addition of hydrocolloids increased the suspension's viscoelastic shear moduli. Alginate displayed strain-thickening behavior and citrus peel pectin exerted a dominant influence on suspension viscoelastic behavior, regardless of the protein preparation used. Combining sugar beet pectin with laccase enzyme resulted in increased viscoelastic moduli. In plant-based burger batter models, the addition of TPP enhanced the elastic modulus across diverse hydrocolloids, mirroring their original properties. These findings demonstrate the distinct contribution of pea protein concentrate versus isolate on the viscoelastic properties of such food model systems.