Structural, Textural, and Functional Properties of Plant-Based Meat Analogs Prepared by High-Moisture Extrusion of Soy–Wheat–Mung Bean Multi-Protein System

High-moisture extrusion (HME) is critical for plant-based meat analogs with meat-like fibrous structures. To expand HME protein sources, this study explored mung bean protein (MBP) substitution (0–50%, dry basis) effects on structural, textural and functional properties of soy protein concentrate (SPC)–wheat gluten (WG) HME products. At 20% MBP addition, the proteins formed a dense layered fibrous network, and the fibrous degree of the extrudates reached the peak. MBP > 40% disrupted the continuous protein network. The optimal rehydration for 20% MBP dried extrudates was 60 °C for 40 min, preserving fibrous texture. Protein interaction analysis indicated that hydrogen bonds and disulfide bonds played an important role in stabilizing the protein network structure. Overall, MBP can be incorporated into SPC-WG-based HME products to diversify protein sources, providing a feasible strategy for developing high-quality, nutritionally diversified plant-based meats.