Optimising high moisture extrusion of alternative proteins for the development of meat-like textures: bridging technology and consumer expectations

ENG- This doctoral thesis focuses on the high-moisture extrusion process (HMEP), a technology that allows the texturization of plant proteins into fibrous structures that mimic meat. The research explores the use of two protein sources valued for their sustainability, low allergenic potential, and growing relevance in the food sector: pea and fava bean. Through several interrelated studies, the optimization of HMEP conditions has been investigated to obtain products with meat-like texture and sensory characteristics aligned with consumer expectations. The results show that both pea and fava bean proteins can generate fibrous structures, and that combining these sources can enhance this effect. This synergy between different protein sources highlights the potential to create strategic formulations that yield meat analogues with improved sensory and structural properties, contributing to a more satisfying consumer experience. On the other hand, although it is known that incorporating fat can bring the texture and nutritional profile of analogues closer to that of meat, it has been observed that oil may interfere with fibre formation during HMEP. Results have also shown that process output parameters can be useful as indicators for monitoring product texture, guiding further research aimed at developing rapid, efficient, and non-invasive methods for predicting product quality. At a molecular level, infrared spectroscopy analysis has revealed that HMEP induces changes in the secondary structure of proteins, identifying significant transformations but also specific methodological limitations that must be considered. Complementarily, the thesis includes an analysis of consumer perception, identifying barriers—such as the perception that the meat analogues are artificial—and motivations—such as ethical and environmental concerns—that may influence the acceptance of these products. Overall, this work offers an integrated perspective that combines technological innovation, scientific knowledge, and insight into consumer behaviour, contributing to the development of more sustainable foods aligned with current social demands