Ingredient Functionality and Structure Development During High-Moisture Extrusion of Plant-Based Meat Analogs

The growing demand for sustainable protein sources has accelerated the development of plant-based meat analogs, with high-moisture extrusion (HME) emerging as a leading technology for producing whole-cut, anisotropic structures. Although substantial progress has been made in understanding plant-protein functionality, protein chemistry, extrusion processing, and structure formation, the information required to translate these relationships into species-specific product design remains dispersed across the literature. This review integrates ingredient functionality, formulation, extrusion hardware, thermomechanical processing, and cooling-die behavior within a unified process–structure–function framework for the development of beef-, chicken-, and fish-like plant-based meat analogs. Particular emphasis is placed on how protein composition and techno-functional properties interact with moisture, temperature, screw configuration, mechanical input, material rheology, and cooling conditions to control network development and anisotropic structure formation. The review further distinguishes the structural requirements of dense and cohesive beef-like matrices, longitudinally fibrous chicken-like structures, and softer layered or flaky fish-like products, and consolidates literature-informed formulation and processing guidance for initial product development. The resulting synthesis offers formulation and processing guidance for developing beef-, chicken-, and fish-like analogs while identifying the experimental evidence needed to establish more reliable, product-specific design criteria.