Contribution to the study of molecular changes in pea proteins during the manufacturing process: structure-function relationship

Pea protein isolate (PPI) is increasingly recognized as a sustainable and functional plant-based protein with promising applications in the food industry. The structure and functional properties of PPI are significantly influenced by processing conditions and environmental factors, such as pH and temperature. These structural modifications directly impact its techno-functional properties, including solubility, emulsifying, and foaming capacities, making it a versatile but complex ingredient for industrial food applications.
This work aims to advance the scientific understanding of the structure-function relationships of PPI through a multi-faceted approach. Firstly, it seeks to develop rapid and reliable analytical methods to monitor molecular changes during industrial extraction processes. Secondly, it examines the influence of environmental and process modifications on PPI structure and functionality, with the ultimate goal of modelling these relationships to optimise PPI’s techno-functional performance.
The research was conducted systematically to address these objectives. The first phase analysed the molecular evolution of PPI during the industrial extraction process, revealing significant structural changes induced by thermal, pH, and compositional effects. The second stage investigated the effects of controlled heat treatment modifications on structural and functional properties, offering insights into the optimisation of extraction conditions. The final part focused on the impact of post-extraction environmental conditions, particularly pH, on PPI’s structural dynamics and functional performance in emulsifying and foaming applications.
The findings demonstrated that PPI’s structural properties, including secondary and tertiary structure, were strongly influenced by processing and environmental conditions. Key structural features, such as β-turns, β-sheets, and aggregates, played a critical role in determining its solubility, surface hydrophobicity, and interfacial activity. Predictive models linking structural and processing parameters to functional outcomes provided a robust framework for optimizing PPI’s performance in food systems.
This work contributes to the growing body of knowledge on plant proteins by elucidating the complex interplay between structure and functionality in PPI. The insights gained from this research offer practical implications for the food industry, guiding the development of tailored PPI ingredients for specific applications and promoting its use in sustainable food systems.