METHODS AND COMPOSITIONS INVOLVING WHEY PROTEIN ISOLATES

• US 20180343890A1
• Filed: 08/03/2018
• Published: 12/06/2018
• Est. Priority Date: 07/19/2010
• Status: Active Grant

• Current Assignee: Wisconsin Alumni Research Foundation (University of Wisconsin System)
• Original Assignee: Wisconsin Alumni Research Foundation (University of Wisconsin System)
• Inventors: ETZEL, Mark R., ROOT, Thatcher, ARUNKUMAR, Abhiram, GEMILI, Seyhun
• Granted Patent: US 10,638,775 B2
• Time in Patent Office: Days
• CPC Class Codes: A23J 1/205 from whey, e.g. lactalbumine
• CPC Class Codes: A23J 3/08 Dairy proteins
• CPC Class Codes: A23V 2002/00 Food compositions, function of food ingredients or processes for food or foodstuffs
• CPC Class Codes: A23V 2200/06 pH modification agent
• CPC Class Codes: A23V 2250/54242 Alpha lactalbumin
• CPC Class Codes: A23V 2250/54244 Beta lactoglobulin
• CPC Class Codes: A23V 2250/5434 Immunoglobulines
• CPC Class Codes: A23V 2250/5438 Sialic acid, glycomacroprotein
• CPC Class Codes: A23V 2300/18 Fractionation
• CPC Class Codes: A23V 2300/34 Membrane process

Abstract

The present invention concerns methods of isolating milk proteins. Methods of the invention include charged ultrafiltration processes that use variations in pH to further separate protein species.

Claims

1. A method for fractionating a protein mixture comprising multiple protein species to obtain a protein of interest comprising:

(a) adjusting the pH of said protein mixture based on the isoelectric point of said protein of interest, thereby rendering a net charge of about zero on said protein of interest,

(b) adjusting the conductivity of said protein mixture such that said multiple species other than said protein of interest are rejected by a charged ultrafiltration membrane; and

(c) contacting said mixture with said charged ultrafiltration membrane to achieve a first permeate and a first retentate, wherein said ultrafiltration membrane has a pore size at least 100 kDa above, or 10×

greater than, at least one of said multiple species other than said protein of interest, wherein said first permeate comprises an increased ratio of said protein of interest as compared to said protein mixture.

2. The method of claim 1, wherein said protein mixture is a milk protein or a whey protein mixture.

3. The method of claim 1, wherein said charged ultrafiltration membrane has a pore size rating of 150-500 kDa.

4. The method of claim 3, wherein said charged ultrafiltration is affected by a ultrafiltration membrane having a pore size rating of about 300 kDa.

5. The method of claim 1, wherein said protein mixture comprises one or more of glycomacropeptide (GMP), alpha-lactalbumin (ALA), immunoglobulin G (IgG), and/or beta-lactoglobulin (BLG).

6. The method of claim 1, wherein said method further comprises subjecting said first permeate to a second charged ultrafiltration to achieve a second permeate and a second retentate.

7. The method of claim 1, wherein said method further comprises subjecting said first retentate to a second charged ultrafiltration to achieve a second retentate and a second permeate.

8. The method of claim 6, wherein said second retentate is recycled into another protein mixture for additional charged ultrafiltration.

9. The method of claim 7, wherein said second permeate is recycled into another protein mixture for additional charged ultrafiltration.

10. The method according to claim 1, wherein said ultrafiltration achieves a purity of about 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% and 99%.

11. The method according to claim 1, wherein said ultrafiltration achieves a yield of about 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% and 99%.

12. The method of claim 3, wherein said ultrafiltration membrane is positively-charged or negatively-charged.

13. The method of claim 1, wherein said conductivity is adjusted to 3-10 mS/cm, in particular to 3-6 mS/cm.

14. The method of claim 1, wherein GMP is separated from ALA, IgG, or BLG;

or wherein ALA is separated from IgG or BLG;

or wherein BLG is separated from IgG.

15. The method of claim 1, wherein said charged ultrafiltration is effected by a multistage cross-flow positively-charged of ultrafiltration membrane.

16. The method according to claim 6, wherein said ultrafiltration achieves a purity of about 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% and 99%.

17. The method according to claim 7, wherein said ultrafiltration achieves a purity of about 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% and 99%.

18. The method according to claim 6, wherein said ultrafiltration achieves a yield of about 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% and 99%.

19. The method according to claim 7, wherein said ultrafiltration achieves a yield of about 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% and 99%.