Process for removing phospholipids and off-flavors from proteins and resulting protein product

Patent metadata

Field	Value
Publication number	US-10945448-B2
Application number	US-86107710-A
Country	US
Kind code	B2
Filing date	Aug 23, 2010
Priority date	Aug 21, 2009
Publication date	Mar 16, 2021
Grant date	Mar 16, 2021

Abstract

Described are methods of removing phospholipids and other off-flavor-causing compounds from edible proteins using a cyclodextrin treatment. The methods include treating soy protein with cyclodextrins such as β-cyclodextrin to form cyclodextrin-compound complexes and then separating the resulting complexes from the protein. Optionally, prior to treating the protein with cyclodextrin, the protein is sonicated and then treated with a phospholipase, such as phospholipase A2. Versions of the methods described herein are capable of removing more than 99% of phospholipids from soy protein.

First claim

We claim:

1. A method for removing compounds that cause off-flavors in proteins, the method comprising:
treating a protein-containing solution comprising a phospholipid with a phospholipase to yield a hydrolytic byproduct of the phospholipid in the solution;
contacting the protein-containing solution with a cyclodextrin for a time wherein the cyclodextrin binds to the hydrolytic byproduct, thereby yielding a complex comprising the cyclodextrin bound to the hydrolytic byproduct; and then
separating the complex from the protein-containing solution.

2. The method of claim 1 wherein the protein-containing solution is derived from oilseeds or oil-bearing cereal grain.

3. The method of claim 1 wherein the contacting step includes contacting the protein-containing solution with an unsubstituted or substituted β-cyclodextrin.

4. The method of claim 1 wherein the cyclodextrin in the contacting step is immobilized on a solid support.

5. The method of claim 1 wherein the treating step includes treating the protein-containing solution with a phospholipase A 2 .

6. The method of claim 1 wherein the treating step includes treating the protein-containing solution with a phospholipase A 2 at a temperature of from about 20° C. to about 50° C. and at a concentration of from about 50 units to about 200 units phospholipase A 2 per gram of protein in the protein-containing solution.

7. The method of claim 1 wherein the hydrolytic byproduct comprises a product selected from the group consisting of a fatty acid, a free fatty acid, an unsaturated fatty acid, and a lysophospholipid.

8. The method of claim 1 wherein the phospholipase is selected from the group consisting of a phospholipase A 1 , a phospholipase A 2 , a phospholipase B, a phospholipase C, and a phospholipase D.

9. The method of claim 1 wherein the protein-containing solution in the treating step comprises purified, defatted protein.

10. A method for removing compounds that cause off-flavors in proteins, the method comprising:
sonicating a protein-containing solution comprising a phospholipid;
treating the protein-containing solution with a phospholipase to yield a hydrolytic byproduct of the phospholipid in the solution, wherein the sonicating is performed prior to the treating;
contacting the protein-containing solution with a cyclodextrin for a time wherein the cyclodextrin binds to the hydrolytic byproduct, thereby yielding a complex comprising the cyclodextrin bound to the hydrolytic byproduct; and then
separating the complex from the protein-containing solution.

11. The method of claim 10 wherein the sonicating step includes sonicating the protein-containing solution for at least about 2 minutes, at a temperature of from about 20° C. to about 70° C., and at a frequency of from about 10 kHz to about 30 kHz.

12. The method of claim 11 wherein the sonicating step includes sonicating the protein-containing solution for at least about 5 minutes.

13. The method of claim 1 wherein the separating step includes separating the complex from the protein-containing solution via ultrafiltration, dialysis, or precipitation.

14. The method of claim 1 wherein the separating step includes separating the complex from the protein-containing solution via isoelectric precipitation at a pH of from about 4 to 5.

15. The method of claim 1 wherein the separating step includes separating the complex from the protein-containing solution via ultrafiltration, wherein the ultrafiltration includes diafiltration.

16. The method of claim 15 wherein the diafiltration is performed with a diafiltration ratio of at least 2×.

17. The method of claim 15 wherein the diafiltration is performed with a diluent of water that includes a cyclodextrin.

18. The method of claim 10 wherein the protein-containing solution includes soy protein.

19. The method of claim 10 wherein the contacting step includes contacting the protein-containing solution with an unsubstituted or substituted β-cyclodextrin.

20. The method of claim 10 wherein the cyclodextrin is immobilized on a solid support.

21. The method of claim 10 wherein the treating step includes treating the protein-containing solution with a phospholipase A 2 at a temperature of from about 20° C. to about 50° C. and at a concentration of from about 50 units to about 200 units phospholipase A 2 per gram of protein in the protein-containing solution.

22. The method of claim 10 wherein the separating step includes separating the complex from the protein-containing solution via ultrafiltration using diafiltration at a diafiltration ratio of at least 2× or isoelectric precipitation at a pH of from about 4 to 5.

23. The method of claim 10 wherein the phospholipase is selected from the group consisting of a phospholipase A 1 , a phospholipase A 2 , a phospholipase B, a phospholipase C, and a phospholipase D.

24. The method of claim 10 wherein the protein-containing solution in the sonicating step comprises purified protein.

25. The method of claim 10 wherein the protein-containing solution in the sonicating step comprises purified, defatted protein.

26. A method for removing compounds that cause off-flavors in proteins, the method comprising:
treating a protein-containing solution comprising soy protein and a phospholipid with a phospholipase to yield a hydrolytic byproduct of the phospholipid in the solution;
contacting the protein-containing solution with a cyclodextrin for a time wherein the cyclodextrin binds to the hydrolytic byproduct, thereby yielding a complex comprising the cyclodextrin bound to the hydrolytic byproduct; and then
separating the complex from the protein-containing solution.

27. The method of claim 26 wherein the phospholipase is selected from the group consisting of a phospholipase A 1 , a phospholipase A 2 , a phospholipase B, a phospholipase C, and a phospholipase D.

Assignees

• Damodaran Srinivasan
• Arora Akshay
• Wisconsin Alumni Res Found

Inventors

• Damodaran Srinivasan
• Arora Akshay

Classifications

• A23J3/16 Primary

  from soybean · CPC title

• A23L11/34

  using chemical treatment, adsorption or absorption · CPC title

• A23L5/273

  using adsorption or absorption agents, resins, synthetic polymers, or ion exchangers · CPC title