Submitted to: American Association of Cereal Chemists Meetings
Publication Type: Proceedings
Publication Acceptance Date: 9/28/2021
Publication Date: N/A
Technical Abstract: Field peas are one of the crops with a growing demand for plant-based protein production. Breeding peas specifically for protein extraction may be beneficial. It may be necessary to consider the types of traits to select for and the level of variation in the traits in order to develop pea cultivars for this end-use. We extracted protein from 26 green and 30 yellow pea genotypes developed by USDA-ARS pea breeding program and grown in two locations in Washington State (Pullman and Fairfield). The proportion of hull in the seed may influence the efficiency of pea protein extraction, wherein a higher hull proportion may reduce the overall protein isolate yield. Our findings indicated that the 56 pea genotypes had a broad variability for hull proportions, ranging from 10.1% to 20.4%. Protein isolate yield varied between 13.7% and 20.0% for the genotypes (mean =16.6%), with protein recovery from dehulled pea flour varying from 49.7% to 64.3%. On average, about 54.9% of the initial sample ended up in the starch-rich byproduct fraction and about 28.5% was lost during the extraction process (soluble materials in the precipitation step). Protein purity of the isolates ranged from 75.4% to 86.0% (N x 6.25). Flour protein content varied widely among genotypes, ranging from 20.5% to 29.3%. Fairfield samples had the highest flour protein content (22.2% to 29.3%) and produced protein isolates with high yields (16.7% to 20.0%). The green peas had relatively higher flour protein (mean=24.5%, range=20.6% to 29.3%) compared to the yellow peas (mean=22.9%, range=20.5% to 26.2%). Protein isolate yield was found to be positively correlated with flour protein content (with r ranging from 0.36 to 0.73). This result may imply that flour protein content could be used as a key selection criterion during the breeding process, particularly at early selection stages. It is also crucial to have further studies on the relationships between protein isolate yield and functional properties.