MAIZE PROTEIN AS A SUSTAINABLE TECHNO-FUNCTIONAL INGREDIENT IN PLANT-BASED MEAT ANALOGUES

ABSTRACT: The production of plant-based meat analogues has emerged as a relevant strategy to address current demands for protein-rich foods and the sustainability of food systems. A key attribute of these products is their ability to reproduce the fibrous texture of animal meat, which depends on protein functionality. Traditionally, soy protein isolate (SPI) and wheat gluten are used for their proven ability to form meat-like structures. However, the reliance on these proteins restricts both nutritional diversity and sensory performance, encouraging the exploration of alternative sources. Among them, pea protein isolate (PPI) has gained attention for its favorable nutritional profile and consumer acceptance. Nonetheless, when used alone, PPI shows technological limitations, particularly its reduced ability to generate stable fibrous textures under extrusion. In Brazil, the maize processing industry generates a protein-rich co-product after starch and oil extraction, known as maize protein concentrate (MPC). Although currently used mainly in animal feed, MPC offers potential advantages for human food applications, combining local availability, sustainability, and functional properties. Its incorporation into plant-based formulations may not only improve the structural performance of PPI-based products but also add value to an underutilized industrial by-product, supporting circular economy practices. Moreover, combining cereal- and legume-derived proteins improves the amino acid balance. Thus, maize protein concentrate with pea protein isolate may enhance both the structure and nutritional quality of meat analogues. This study evaluated the incorporation of MPC in high-moisture extruded meat analogues (HMMA) produced with different proportions of SPI and PPI. Seven formulations (HME1–HME7) were processed using a twin-screw extruder under standardized conditions. The extrudates were characterized in terms of structural properties, including physical dimensions, texture profile (hardness and firmness), and surface morphology analyzed by scanning electron microscopy (SEM). The results showed that high PPI levels impaired structural cohesion, preventing the formation of stable analogues. Conversely, the inclusion of MPC had distinct effects: when combined with SPI, it resulted in rougher textures, while in formulations with PPI, it enhanced stability and robustness. SEM analyses supported these findings, revealing more compact surfaces in SPI-rich samples and more porous, heterogeneous morphologies in formulations with higher proportions of PPI and MPC. In conclusion, the findings demonstrate that both protein source and ratio are critical factors in determining the quality of plant-based meat analogues. MPC emerges as a functional and sustainable ingredient, capable of improving the structural integrity of pea-based products while contributing to circular economy strategies within the plant-based food industry.