Residual Lipids Affect Structural and Functional Properties of Oat and Mung Bean Protein Isolates

Background and Objectives In recent years, plant protein sources such as oat and mung bean have been explored to diversify the food supply. Residual lipids in protein isolates may influence their structural and techno‐functional properties and are often overlooked. This work aimed to characterize residual lipids and evaluate their impact on the structural and techno‐functional properties of oat and mung bean protein isolates. Findings Initial lipid contents were 34.81% and 3.57% in oat and mung bean protein extracts, respectively. After partial defatting with hexane, residual lipids remained and were enriched in phospholipids, accounting for 11.74% and 87.37% of the residual lipid fraction in oat and mung bean isolates, respectively. Total lipid extraction with chloroform‐methanol induced protein aggregation in oat isolates, while mung bean proteins showed limited structural changes. It also impacted techno‐functional properties since foaming capacity increased (319.05% vs. 43.52% in oat and 288.74% vs. 32.25% in mung bean), whereas the emulsifying activity index decreased (29.32 vs. 60.39 m 2 /g for oat and 39.51 vs. 54.14 m 2 /g for mung bean). Conclusions, Significance, and Novelty These results demonstrate that residual lipids significantly influence protein structure and techno‐functional properties, with effects strongly dependent on the protein matrix. Accounting for residual lipids is therefore essential when designing and optimizing plant‐based food formulations.