Evaluating Protein from Winter Cover Crops and Leveraging Their Unique Characteristics Through Blending

The growing demand for sustainable plant proteins has driven interest in winter cover crops like winter peas, camelina, and pennycress. While pea protein studies have largely focused on spring yellow peas as a source, winter peas offer additional environmental benefits and a high protein content (~20-35%), making them a promising alternative protein source. Camelina and pennycress seeds are also high in protein and thus have potential as sources of novel protein. However, these proteins have limitations in terms of their functionality and nutritional quality.

The objective of this work was to evaluate the protein characteristics of winter peas compared to spring yellow peas and identify functional synergies resulting from blending winter pea, camelina, and pennycress proteins.

Winter and spring peas were grown under similar agronomic conditions and used to isolate protein following alkaline double solubilization with isoelectric precipitation. Camelina and pennycress proteins were isolated following a previously developed method: salt extraction with ultrafiltration. Protein yield and purity were monitored. Protein blends of winter pea, camelina, and pennycress proteins were prepared in three ratios: 34:33:33, 50:25:25, and 20:40:40. Protein profile, surface properties, protein denaturation, and functional properties (solubility, gelation, and emulsification) were evaluated.  

Winter pea protein isolates had similar protein purity (87-88%), protein yield (65-68%), and structural characteristics to spring pea protein isolates, with slight functional differences. All blends showed synergistic gelling improvements without significant differences (~7-8N), with only PcPI forming a gel (~8N). The 20:40:40 blend exhibited synergistic improvements in emulsification capacity by 1.2-1.7 fold (with significant differences) over individual proteins. These results highlighted the potential of protein blending to improve functionality.

This research will accelerate the commercialization of winter crops as novel sources of sustainable protein for human consumption by employing innovative strategies, such as protein blending. Developing an end-use market will encourage farmers to adopt these crops.