A Hybrid Dry and Aqueous Fractionation Method to Obtain Protein-Rich Fractions from Quinoa (Chenopodium quinoa Willd)

Combination of dry and aqueous fractionation is investigated to obtain protein-rich fractions from quinoa in a milder and more sustainable way compared to conventional wet fractionation. Dry fractionation of quinoa involved milling and subsequent air classification, generating a protein-enriched embryo fraction. Subsequently, this fraction was milled, suspended, and further fractionated by aqueous phase separation. The efficiency of aqueous phase separation could be improved by addition of NaCl (0.5 M). Finally, the top aqueous phase was decanted and ultrafiltered, resulting in a protein purity of 59.4 w/dw% for the 0.5 M NaCl-protein solution and a protein yield (gram protein obtained/gram protein in seed) of 62.0 %. Having used 98 % less water compared to conventional wet extraction, the hybrid dry and aqueous fractionation is a promising method for industry to create value from quinoa in a more economic and sustainable friendly way while minimizing the impact on quinoa’s native protein functionality.