Exploring textural, solubility and rheological characteristics of high-moisture extruded meat analogues: effects of wheat gluten and rice protein incorporation in pea protein isolate and feed moisture levels

Abstract

This research explores the development of high-moisture meat analogues (HMMA) by blending wheat gluten (WG) and rice protein (RP) with pea protein isolate (PPI) in a twin-screw extruder under high-moisture extrusion conditions. The study investigates the effects of incorporating RP and WG with PPI on textural, rheological and colour properties, as well as the underlying protein–protein interactions through protein solubility. From the compositional analysis of these secondary ingredients, there was no significant difference between them. However, results from the extrusion indicated that WG-PPI showed good fibration and higher instrumental anisotropy than RP-PPI blend extrudates. RP-PPI blends exhibit inferior textural and rheological properties, attributed to RP's limited crosslinking ability within the protein matrix. This has resulted in a poor structure and lower textural values at higher incorporation of RP (50%) in the pea protein matrix. This was due to the insoluble protein fraction of the RP resulting in a non-melting in the extrusion barrel. These findings underscore the importance of understanding protein interactions in developing optimised HMMA formulations, paving the way for further exploration into developing modified RP with improved physiochemical properties which can be integrated into meat analogues.