Deamidation promotes the combination of novel proteins with volatile compounds and improves their flavor characteristics.

From the paper

Abstract

The undesirable flavor of plant-based proteins severely limits their high-value utilization. Consequently, developing green flavor-modification techniques and clarifying their regulatory mechanisms are of great importance. This study systematically investigated the effects of different deamidation degrees on the structure, flavor properties, and flavor-binding mechanisms of novel proteins, including chickpea protein (CP), oat protein (OP), and Pleurotus eryngii protein (PEP). The results indicated that deamidation effectively improved the flavor quality of the protein and reduced the relative content of key off-flavor compounds, such as decanal, 1-hexanol, and dodecanal. Following deamidation, the number of binding sites between proteins and flavor compounds increased, with the values for CP, OP, and PEP rising from 1.68 to 2.54 to 2.27-3.96, from 1.24 to 1.35 to 4.15-4.40, and from 1.27 to 1.61 to 2.45-2.51, respectively. Further analysis revealed that hydrophobic interactions and hydrogen bonding mainly drove the interactions between proteins and flavor compounds. Molecular simulation confirmed that deamidated proteins exhibit stronger binding affinity for flavor compounds. In summary, deamidation improves the flavor characteristics of plant proteins by inhibiting the release of undesirable flavor compounds and enhancing the binding capacity toward volatile flavor compounds. This study systematically elucidates, at the molecular level, how deamidation regulates the structure of plant proteins and their binding and release behaviors toward flavor compounds. It provides a new theoretical framework and methodological basis for the targeted flavor design and precise regulation of plant-based foods.