In order to determine the effect of extrusion, baking, and cooking on the protein quality of yellow and green split peas, a rodent bioassay was conducted and compared to an in vitro method of protein quality determination. The Protein Digestibility-Corrected Amino Acid Score (PDCAAS) of green split peas (71.4%) was higher than that of yellow split peas (67.8%), on average. Similarly, the average Digestible Indispensable Amino Acid Score (DIAAS) of green split peas (69%) was higher than that of yellow split peas (67%). Cooked green pea flour had lower PDCAAS and DIAAS values (69.19% and 67%) than either extruded (73.61%, 70%) or baked (75.22%, 70%). Conversely, cooked yellow split peas had the highest PDCCAS value (69.19%), while extruded yellow split peas had the highest DIAAS value (67%). Interestingly, a strong correlation was found between in vivo and in vitro analysis of protein quality (R2 = 0.9745). This work highlights the differences between processing methods on pea protein quality and suggests that in vitro measurements of protein digestibility could be used as a surrogate for in vivo analysis.
Keywords: DIAAS; Extrusion; PDCAAS; PER; baking.