Characteristics of faba bean protein-based high-moisture meat analogues incorporating brewers' spent grain through extrusion

Abstract

Extrusion is a continuous, versatile process widely regarded as the most cost-effective method for producing high-moisture meat analogue (HMMA). To achieve the desired structural and textural characteristics in meat analogue products, a strategic combination of appropriate ingredients and their optimal ratios is essential. This study investigated the introduction of a fibrous structure in faba bean protein-based HMMA (27 to 39 % protein content) by varying the total solids content (33, 36 and 39 %) and incorporating brewers' spent grain (0, 3 and 6 %) as a structural enhancer. The findings indicate that increasing the solids content promotes fibrillation and improves the overall meat analogue texture. Notably, brewers' spent grain (BSG), an underutilised food by-product, was successfully incorporated into the formulation, promoting fibrous structure formation and enhancing meat texture. However, optimisation is necessary, as while a 3 % BSG inclusion improved extrudate quality, a 6 % inclusion had detrimental effects. This study contributes to the development of sustainable food systems by demonstrating spent grain's potential to strengthen meat analogue structure and texture, while contributing to the positioning of faba bean protein as an untapped, sustainable plant protein source. Further, this study proposes an alternative pathway for repurposing fermented waste (i.e., BSG) by converting it into a functional ingredient that enhances its economic value while reducing environmental impact.