Modeling and optimization of pea protein hydrolysis: linking process parameters to technological functionality

The limited technological functionality of plant proteins often hinders their application in food systems. Although enzymatic hydrolysis is widely promoted as a “green” strategy for improving these properties, a systematic understanding of how process parameters translate into specific functional outcomes remains limited. This study investigated the link between hydrolysis process parameters (enzyme content (Alcalase 2.4 L), hydrolysis time, and substrate concentration), technological properties (solubility, water- and oil-holding capacities, emulsifying and foaming properties) and structural features (molecular weight distribution, free-SH groups, surface hydrophobicity) of a pea protein concentrate (PPC) using a Box–Behnken design. Enzyme concentration emerged as the predominant factor significantly influencing all functional responses. Experimental data revealed three distinct hydrolysis ranges (limited, intermediate, and extended), each associated with specific and predictable technological performances. These relationships were integrated into a functionality map that enables the selection of hydrolysis conditions according to the desired functional profile and the identification of trade-offs. Limited hydrolysis (DH < 10%) improved the oil-holding and foaming properties, whereas extended hydrolysis (DH > 20%) enhanced solubility. Beyond these empirical findings, the study provides a transferable process design approach applicable to other protein matrices.