Abstract: High-moisture extruded plant-based protein meat can be used as a sustainable alternative to animal protein owing to its ready-to-eat convenience, elasticity, and fibrous texture, alleviating the problem of insufficient supply of animal protein. However, existing products still exhibit shortcomings such as insufficient fiber structure and lack of textural layering, which negatively impact sensory qualities like mouthfeel. Consequently, the incorporation of ingredients to enhance the fiber structure of high-moisture extruded plant-based protein meat has become a key focus for both researchers and manufacturers. Currently, a significant amount of research focuses on incorporating food ingredients such as polysaccharides and proteins during the high-moisture extrusion process. These ingredients aim to improve the fiber structure by interacting covalently or non-covalently with proteins in the raw material. Nevertheless, the mechanism underlying the synergistic effect still lacks systematic elaboration. This review first provides a systematic overview of the formation mechanism of the fiber structure of high-moisture extruded plant-based protein meat and the methods for its detection. Then it summarizes the mechanisms by which different types of ingredients (polysaccharides, plant proteins, enzymes, and organic acids) enhance the density and strength of the fiber structure. The aim is to explore the potential of various ingredients in improving the fiber structure of high-moisture extruded plant-based protein meat, thereby providing a theoretical foundation for addressing the bottleneck of insufficient fiber structure.

Key words: plant-based protein meat; fiber structure; high-moisture extrusion; polysaccharides; plant proteins