Pea variety and dehulling effects on biorefinery efficiency and fraction quality

• Pea varieties have impact on protein recovery, composition, nutritional quality. • The first decanting step of the pH-shift process yielded a pure starch fraction. • The dehulling step comprises 30 % of the total lost protein. • Decanted water fractions comprise 70 % of the total lost protein. • At least 42.6 % of the protein within the whole pea is lost during wet fractionation. This study investigated the potential of yellow peas, with and without dehulling, as a biorefinery feedstock for sequentially producing multiple products such as fiber, starch, and proteins. It also investigated the effect of two different pea varieties, Ingrid and Clara, on the biorefinery efficiency and the quality of the recovered fractions by analyzing the composition and mass balance of four main fractions (hull, starch-rich, soluble dietary fiber/protein-rich, and main protein-rich fractions) generated during wet fractionation via the pH-shift method. Among dehulled samples (pea flour and crude protein isolate) Ingrid resulted in higher purity in specific fractions such as protein, starch, and dietary fiber than Clara while no difference was observed between the whole (with hull) and dehulled pea seed samples. Protein extraction efficiency, amino acid, and fatty acid profile did not show significant differences between whole and dehulled samples. Overall, these findings underscore the versatility of peas as a multiple-product biorefinery feedstock using the pH-shift method with the impact of variety being more pronounced on protein fraction quality, while preprocessing steps like dehulling play a decisive role in optimizing the composition and purity of fiber- and starch-rich fractions for targeted applications.