Aglucone isoflavone enriched vegetable protein extract and isolate and process for producing

• US 5,763,389 A
• Filed: 04/12/1996
• Issued: 06/09/1998
• Est. Priority Date: 10/12/1993
• Status: Expired due to Term

• Current Assignee: Archer Daniels Midland Company
• Original Assignee: Protein Technologies International, Inc. (Corteva, Inc.)
• Inventors: Bryan, Barbara A., Shen, Jerome L.
• Primary Examiner(s): Russel, Jeffrey E.
• Application Number:
  US08/307,752
• Time in Patent Office: 788 Days
• Field of Search: 435/68.1, 435/125, 514/2, 514/8, 514/455, 514/456, 530/343, 530/370, 530/377, 530/378, 530/407, 530/412, 530/414, 530/419, 530/420, 530/427, 549/403
• US Class Current: 435/68.1
• CPC Class Codes: C07K 14/415 from plants
• CPC Class Codes: C12P 17/06 containing a six-membered hetero ring, e.g. fluorescein

Abstract

Aglucone isoflavone enriched vegetable protein extract and isolate and processes for producing and recovering are disclosed. The aglucone isoflavone extract is made by extracting a vegetable protein material comprising glucone isoflavones with an aqueous extractant having a pH above about the isoelectric point of the protein material to produce an aqueous extract, and reacting the glucone isoflavones with a sufficient amount of beta-glucosidase enzyme or esterase enzyme for a time period, temperature, and pH sufficient to convert at least a majority of the glucone isoflavones in the extract to aglucone isoflavones and thereby produce the aglucone isoflavone enriched extract. The aglucone isoflavone enriched isolates are produced by adjusting the pH of the reacted extract to about the isoelectric point of the vegetable protein material to precipitate the protein material, and separating the protein material to produce an aglucone enriched protein isolate.

Claims

1. A vegetable protein isolate having a dry basis genistein content of about 1.5 to about 3.5 mg/gram and a dry basis daidzein content of about 1.0 to about 3.0 mg/gram.

2. A process for recovering at least a majority of isoflavones from a vegetable protein material, comprising:

(a) extracting a vegetable protein material containing glucone isoflavones with an aqueous extractant having a pH above about the isoelectric point of said vegetable protein material and subsequently removing insoluble materials from said extractant to produce an aqueous extract containing protein and glucone isoflavones;

(b) contacting said glucone isoflavones in said extract with an effective amount of enzyme at a temperature, pH, and for a time sufficient to convert at least a majority of said glucone isoflavones in said extract to less soluble aglucone isoflavones to produce an aglucone isoflavone enriched extract;

(c) adjusting the pH of said aglucone isoflavone enriched extract to about the isoelectric point of said protein in said aglucone isoflavone enriched extract to precipitate a protein material containing at least a majority of isoflavones from said vegetable protein material; and

(d) separating the precipitated protein material to recover a protein isolate containing at least a majority of said isoflavones from said vegetable protein material.

3. The process as set forth in claim 2 wherein said enzyme is selected from the group consisting of beta-glucosidase enzymes and esterase enzymes.

4. The process as set forth in claim 2 wherein at least 65% of said isoflavones in said vegetable protein material are recovered in said isolate.

5. The process as set forth in claim 2 wherein at least 80% of said isoflavones in said vegetable protein material are recovered in said isolate.

6. The process as set forth in claim 2 wherein said vegetable protein material comprises a soybean material.

7. The protein isolate of claim 2.

8. The protein isolate of claim 4.

9. The protein isolate of claim 5.

10. A process for producing an aglucone isoflavone rich protein isolate, comprising:

extracting a vegetable protein material containing glucone isoflavones with an aqueous extractant having a pH above about the isoelectric point of said vegetable protein material to produce an aqueous extract containing protein and glucone isoflavones;

removing insoluble materials from said extract;

contacting said glucone isoflavones in said extract with an effective amount of at least one of a beta-glucosidase enzyme or esterase enzyme at a temperature, a pH, and for a time sufficient to convert at least a majority of said glucone isoflavones to aglucone isoflavones;

precipitating a protein isolate containing aglucone isoflavones from said extract by adjusting the pH of said extract to about the isoelectric point of said protein after contacting said glucone isoflavones with said enzyme to convert said glucone isoflavones to said aglucone isoflavones.

11. The process set forth in claim 10 wherein said vegetable protein material is extracted with an aqueous extractant having a pH of about 6 to about 10.

12. The process set forth in claim 10 wherein said enzyme is contacted with said glucone isoflavones in said extract for a period of from about 2 hours to about 24 hours to convert said glucone isoflavones to said aglucone isoflavones.

13. The process set forth in claim 10 wherein said enzyme is contacted with said glucone isoflavones in said extract at a temperature of about 40°

C. to about 60°

C. to convert said glucone isoflavones to said aglucone isoflavones.

14. The process set forth in claim 10 wherein said enzyme is a residual enzyme.

15. The process set forth in claim 10 wherein said enzyme is a supplemental enzyme.

16. The process set forth in claim 10 wherein said vegetable protein material is a soybean material.

17. The process set forth in claim 16 wherein said protein isolate containing said aglucone isoflavones is precipitated from said extract by adjusting the pH of said extract to between about pH 4 to about pH 5.

18. The process set forth in claim 10 wherein substantially all glucone isoflavones are converted to aglucone isoflavones.

19. The process set forth in claim 10 further comprising separating said precipitated protein isolate containing aglucone isoflavones from said extract.

20. The process set forth in claim 19 wherein washing of said separated protein isolate is avoided.

21. The process set forth in claim 19 wherein said separated protein isolate is washed with water in an amount which is less than about 4 times the weight of said separated protein isolate.

22. The aglucone isoflavone rich protein isolate produced by the process of claim 10.

23. A process for producing an aglucone isoflavone rich extract, comprising:

extracting a vegetable protein material containing glucone isoflavones with an aqueous extractant having a pH above about the isoelectric point of said vegetable protein material to form an extract containing protein and glucone isoflavones;

removing insoluble materials from said extract; and

contacting said glucone isoflavones in said extract from which said insoluble materials have been removed with an effective amount of at least one of a beta-glucosidase enzyme or an esterase enzyme at a temperature, pH, and for a time sufficient to convert substantially all of said glucone isoflavones to aglucone isoflavones.

24. The process set forth in claim 23 wherein said vegetable protein material is extracted with an aqueous extractant having a pH of about 6 to about 10.

25. The process set forth in claim 23 wherein said enzyme is contacted with said glucone isoflavones in said extract for a period of from about 2 hours to about 24 hours to convert said glucone isoflavones to said aglucone isoflavones.

26. The process set forth in claim 23 wherein said enzyme is contacted with said glucone isoflavones in said extract at a temperature of about 40°

C. to about 60°

C. to convert said glucone isoflavones to said aglucone isoflavones.

27. The process set forth in claim 23 wherein said vegetable protein material is a soybean material.