Effects of different soy protein concentrates on the structuring potential and extrudate quality of meat analogues via high moisture extrusion

Abstract

Soy protein concentrate (SPC) is a common ingredient in high moisture extruded meat analogues. However, commercial SPCs can have diverse properties which can affect extrusion outcomes. Yet, the variations between commercial SPCs are often beyond the control of meat analogue manufacturers. Therefore, there is a need to understand how the properties of different commercial SPCs would affect extrudate quality so that manufacturers can screen their ingredients for the desired properties. By investigating a broad range of properties, this study served to study the SPCs on a holistic level and highlight the properties correlated to extrudate quality. The compositional, physicochemical and rheological properties of four SPCs were studied, and their properties were related to the macrostructure and mechanical properties of the extrudates. The study found significant differences between the SPCs for most of the studied properties. Correlation analysis revealed that compositional properties and pH correlated better with extrusion outcomes as compared to other physicochemical properties. Through simple regression analysis, the rheological behaviour of the SPC samples could be related to the fibrous structuring potential of the samples, suggesting that structural breakdown might be an important aspect of fibre formation. The study showed that commercial SPCs indeed varied based on suppliers, and these variations have an apparent impact on the extrudate quality that should not be overlooked, especially for quality control.