Quinoa protein concentrate, production and functionality
View Patent ↗The present invention relates to a new source of high quality plant protein, termed, “ quinoa protein concentrate (QPC)”, which contains at least about 50 wt % protein which is food-grade and/or pharmaceutical-grade and methods of preparing such protein concentrates as well as starch, oil, and fiber from quinoa grain. The quinoa protein concentrate of the invention is useful as food ingredients, infant formula ingredients, cosmetic ingredients, pet food ingredients, and animal feed supplements.
1. A quinoa fruit protein concentrate having a protein content of at least about 50 wt % on a dry weight basis.
2. The quinoa fruit protein concentrate of claim 1 wherein said protein content is at least about 70 wt % on a dry weight basis.
3. The quinoa fruit protein concentrate of claim 1 wherein said protein content is at least about 90 wt % on a dry weight basis.
4. The quinoa fruit protein concentrate of claim 1 which is in dry powdered form.
5. A method of processing quinoa fruit comprising the steps of:
comminuting or milling the quinoa fruit;
separating the embryo-rich fraction from the perisperm-rich fraction of the comminuted quinoa fruit;
extracting the oil from the embryo-rich fraction of the comminuted quinoa fruit to produce defatted quinoa;
extracting the protein from the defatted quinoa using an alkaline solution to solubilize the protein in the defatted quinoa;
separating solubilized protein in the alkaline solution from the insoluble fiber of the defatted quinoa ; and
drying the separated protein, whereby a quinoa protein concentrate containing at least about 50 wt % protein is obtained.
6. The method of claim 5 further comprising a step of purifying the protein by isoelectric precipitation at a pH of about 3.0 to about 6.5 after the step of separating solubilized protein but before the step of drying the separated protein.
7. The method of claim 5 wherein the pH of the resulting alkaline solution having the solubilized protein is in the range of about 8.0-12.0.
8. The method of claim 5 wherein the oil extraction is carried out by a nonpolar solvent or a mechanical process.
9. The method according to claim 5 wherein the step of separating the embryo-rich fraction from the perisperm-rich fraction of the comminuted quinoa fruit is performed by a technique selected from the group consisting of sieving, aspiration, air classification and vibration.
10. The method according to claim 5 further comprising the step of collecting the perisperm-rich fraction resulting from the step of separating the embryo-rich fraction from the perisperm-rich fraction of the comminuted quinoa fruit, whereby a quinoa starch product is obtained.
11. The method according to claim 5 further comprising the step of collecting the extracted quinoa oil from the oil extraction step, whereby a quinoa oil product is obtained.
12. The method according to claim 5 further comprising the steps of:
collecting the insoluble fiber from the protein separation step; and
neutralizing the collected fiber, whereby a quinoa fiber product is obtained.
13. The method according to claim 5 further comprising the step of neutralizing the separated protein prior to the drying step.
14. The method according to claim 5 further comprising the steps of:
precipitating the separated protein;
isolating the precipitated protein from the supernatant; and
neutralizing the precipitated protein prior to the drying step.
15. A method of processing quinoa fruit comprising the steps of:
milling the quinoa fruit;
extracting the oil from the flaked quinoa leaving defatted quinoa;
collecting the extracted quinoa oil, whereby a quinoa oil product is obtained;
comminuting the defatted quinoa;
extracting the protein from the defatted quinoa using an alkaline solution to solubilize the protein in the defatted quinoa;
separating solubilized protein from the insoluble fiber of the defatted quinoa ; and
drying the separated protein, whereby a quinoa protein concentrate containing at least about 50 wt % protein is obtained.
16. The method according to claim 15 further comprising the step of:
neutralizing the separated fiber, whereby a quinoa starch and fiber product is obtained; and
separating the quinoa starch from the quinoa fiber in the quinoa starch and fiber product.
17. The method according to claim 15 further comprising the step of neutralizing the separated protein prior to the drying step.
18. The method according to claim 15 further comprising the steps of:
precipitating the separated protein;
isolating the precipitated protein from the supernatant; and
neutralizing the isolated protein prior to the drying step.