Incorporation of brewer's spent grain into plant‐based meat analogues: benefits to physical and nutritional quality

Summary Brewer's spent grain (BSG) is the major by‐product of brewery industry. Due to being rich in dietary fibres and proteins, it has great potential to be upcycled in plant‐based foods and contribute to the sustainability of our food system. This study investigated the incorporation of BSG at different concentrations to soy protein‐based high‐moisture meat analogues (HMMAs). Colour, textural properties, and macrostructure of the resulting HMMAs were examined. In vitro protein digestibility of selected HMMAs was also measured. At 15% BSG incorporation level, the presence of BSG favoured texturisation and lowered the hardness of HMMAs. However, higher BSG incorporation levels impaired the formation of a fibrous structure in the HMMAs that mimics the mouthfeel of animal‐based products. When extrusion feed moisture increased from 60% to 70%, the hardness and chewiness of the HMMAs decreased from 223.18 and 188.94 N to 127.80 and 103.16 N, respectively, while the cohesiveness and springiness were not significantly affected. In general, the higher the BSG incorporation level, the darker and browner were the HMMAs. IVPD of HMMAs varied from 74.58% to 76.15% and was higher in the HMMAs containing BSG, indicating that BSG complements soy protein digestibility. BSG incorporation may improve the texture of HMMAs and contribute to the intake of dietary fibre.