Rheological properties of pea protein melts used for producing meat analogues

Artikel i vetenskaplig tidskrift, 2025

Understanding the rheological properties of protein melts is critical in the design of meat analogues and the formation of texturised products from plant-based proteins. This study investigated the influence of temperature, moisture content (MC) and protein concentration on the
rheological properties of pea protein isolate and pea fibre
blends. The blends were chosen as an experimental space where it is possible to extrude fibrous meat analogues using high-moisture extrusion. Mechanical spectra by small amplitude oscillatory shear were determined using conventional rherometry and were compared to closed cavity rheometry (CCR) to extend the available temperature range. All blends behaved as polymer melts in the rubbery region with
moduli increasing with frequency, and storage modulus
larger than loss modulus for temperature 40–90°C, MC
54–63%, protein concentration 75–85%. Complex viscosity
was strongly shear thinning. The relative influence of the
parameters from additive and linear mixed models showed
an influence of temperature > MC > concentration. The
increase of modulus with concentration was quite weak
and not statistically significant. The behaviour of the complex modulus was explained well with an Arrhenius-type log-linear mixed model. Conventional rheometry agreed well with CCR, showing an exponential decrease of moduli between 40 and 130°C.