Compositional diversity in pea flour: Effects on functional properties

Peas, recognized for their nutritional richness and sustainability in food systems, are increasingly important for global food security. Although flours vary widely in composition, the effects of starch and protein on their functional properties in food applications remain poorly understood. To investigate this, we strategically selected 30 pea accessions from 265 accessions based on genetic variation and explored how the composition of pea flours relates to their functional properties. Analysis of the flours revealed wide-ranging composition across the accessions, with total starch (29-51 %), protein (22-35 %), amylose (11-25 %) and amylopectin (10-36 %) content on a dry flour basis. Notably, the composition was significantly associated with pea phenotype. Peas with lower total starch and amylopectin levels, along with higher fibre and amylose content, were generally more wrinkled. Protein profiles, assessed through SDS-PAGE, revealed variations in legumin and vicilin content. Peas with lower legumin and higher vicilin and low-molecular-weight pea albumin fractions, such as PA 1 and lectins, were likely to be more wrinkled. Functional assessments highlighted diverse properties linked closely to flour composition. Higher protein content corresponded to lower protein solubility, particularly pronounced in smaller particles where protein-starch/fibre interactions may be enhanced. Thermal sensitivity, assessed by comparing volume changes in pea suspensions before and after heating, expressed as the swelling factor (SF), also differed depending on composition. Flours with lower amylopectin exhibited lower sensitivity and a reduced SF, attributed to lower total starch and legumin levels. Conversely, flours with higher amylopectin content showed higher thermal sensitivity and variable SF, associated with higher total starch and legumin levels. This study reveals the impact of pea composition on functionality, providing insights for utilizing diverse pea varieties in the development of innovative pea-based ingredients.