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

Abstract

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.

Composition, Protein Profile and Rheological Properties of Pseudocereal-Based Protein-Rich Ingredients

“…The protein-rich ingredients, QPRF, APRF, BPRF, and RPC showed higher ash contents (3.6%, 6.9%, 3.0%, and 3.4%, respectively) than the regular flours QWGF, QDF, AWGF, BDF, RF, and MF (2.3%, 1.8%, 2.4%, 1.5%, 0.8%, and 0.7%, respectively). Protein-rich flours are usually produced using dry fractionation approaches [ 28 ], classifying the parts of the grain that are rich in protein (e.g., embryo fraction) which results in a concomitant increase in other components such as minerals [ 5 , 25 , 39 ]. These pseudocereal protein-rich fractions with higher ash content would be expected to be enriched in selected minerals such as phosphorus, magnesium, and potassium that are located in embryonic tissues [ 33 , 40 ].…”

“…Protein-enriched fractions can be prepared from such pseudocereal grains using two principal approaches—dry or wet fractionation techniques [ 27 ]. Dry fractionation employs mechanical forces (milling and air/size classification) and is a more sustainable means of obtaining protein-rich fractions, while wet fractionation techniques use large quantities of water, chemicals (e.g., for pH adjustment), and a final drying step that consumes energy [ 4 , 28 ]. Therefore, protein-rich fractions from pseudocereals can offer unique nutritional and technological properties that have not yet been fully investigated or tested in food applications [ 29 , 30 , 31 ].…”

Characterization of Quinoa Defatted by Supercritical Carbon Dioxide. Starch Enzymatic Susceptibility and Structural, Pasting and Thermal Properties

“…However, its performance as an ingredient in food applications needs to be established since it is well known that the removal of lipids affects the techno-functional properties and starch digestibility of flour (Ye et al, 2018;Srichuwong et al, 2017). Diverse approaches have been attempted to create value from quinoa in an economic and sustainable way while minimizing the impact on quinoa's protein and starch functionality (Avila Ruiz, Arts, Minor, & Schutyser, 2016;. However, the effect of defatting quinoa by SCCO2 extraction on the microstructure, technological and nutritional properties of defatted flour has never been investigated so far.…”

The Revival of Quinoa: A Crop for Health

“…Several methods to obtain protein isolates have been described [35,48], consisting mainly of 11S globulins and 2S albumins, the main contributor of sulfur amino acids Cys and Met, which are limiting in legumes and they also contain interesting amounts of Arg [49]. Also, various high protein-rich fractions of interest can be obtained for the food industry [50]. An additional nutritional advantage of quinoa is that it may be consumed by celiac patients, since it is considered a gluten-free grain because it contains low concentrations of prolamins [51] and has a distant phylogenetic link with gluten containing cereals such as gramineas (wheat, barley and rye).…”