Degumming of edible oils by ultrafiltration

• US 6,797,172 B2
• Filed: 11/25/2002
• Issued: 09/28/2004
• Est. Priority Date: 05/24/2000
• Status: Expired due to Term

• Current Assignee: Texas A&M University System
• Original Assignee: Texas A&M University System
• Inventors: Farr, Walter E., Koseoglu, Semih Sefa, De Greyt, Wim F. S., Kellens, Marc
• Primary Examiner(s): Therkorn, Ernest G.
• Application Number:
  US10/296,951
• Publication Number:
  US 20030209493A1
• Time in Patent Office: 673 Days
• Field of Search: 210/180, 210/650, 210/651, 210/653, 210/654, 210/500.42, 426/490, 426/492, 426/495, 426/662, 554/175
• US Class Current: 210/651
• CPC Class Codes: A23J 7/00 Phosphatide compositions for foodstuffs, e.g. lecithin
• CPC Class Codes: A23V 2002/00 Food compositions, function of food ingredients or processes for food or foodstuffs
• CPC Class Codes: A23V 2300/14 Extraction
• CPC Class Codes: A23V 2300/34 Membrane process
• CPC Class Codes: A23V 2300/38 Multiple-step
• CPC Class Codes: B01D 2311/04 Specific process operations in the feed stream; Feed pretreatment
• CPC Class Codes: B01D 2311/06 Specific process operations in the permeate stream
• CPC Class Codes: B01D 2311/12 Addition of chemical agents
• CPC Class Codes: B01D 2311/2673 Evaporation
• CPC Class Codes: B01D 61/027 Nanofiltration
• CPC Class Codes: B01D 61/145 Ultrafiltration
• CPC Class Codes: B01D 61/146 comprising multiple ultrafiltration steps
• CPC Class Codes: B01D 61/147 Microfiltration
• CPC Class Codes: B01D 61/16 Feed pretreatment
• CPC Class Codes: B01D 71/34 Polyvinylidene fluoride
• CPC Class Codes: C07F 9/103 Extraction or purification by physical or chemical treatment of natural phosphatides; Preparation of compositions containing phosphatides of unknown structure
• CPC Class Codes: C11B 3/008 by filtration, e.g. including ultra filtration, dialysis C11B3/005 takes precedence

Abstract

A process for refining and degumming edible oils by ultrafiltration which produces a permeate fraction with reduced phosphatide content and retentate with increased phosphatide content, and wherein the ultrafiltration membrane is composed of a polymerical polymer of a vinylidene difluoride monomer.

Claims

1. A process for treating oil, comprising the steps of:

(a) contacting the oil with an ultrafiltration membrane, wherein the ultrafiltration membrane comprises a polymer or copolymer of a vinylidene difluoride monomer;

(b) separating the oil into a permeate fraction having a reduced phosphatide content and a retentate fraction having an increased phosphatide content; and

(c) treating the retentate fraction to produce a lecithin product.

2. The process claim 1, wherein the step of contacting the oil with the ultrafiltration membrane is conducted in the absence of solvent.

3. The process claim 1, wherein treating the retentate fraction further comprises the steps of:

(a) adding a solvent to the retentate fraction;

(b) contacting the retentate fraction with added solvent with an ultrafiltration membrane, wherein the ultrafiltration membrane comprises a polymer or copolymer of a vinylidene difluoride monomer;

(c) separating the retentate fraction with added solvent into a secondary permeate stream and a substantially oil-free secondary retentate stream; and

(d) evaporating solvent from the secondary retentate stream to produce a substantially oil-free lecithin powder product.

4. The process claim 1, wherein treating the retentate fraction further comprises the steps of:

(a) adding a solvent to the retentate fraction;

(b) contacting the retentate fraction with added solvent with an ultrafiltration membrane, wherein the ultrafiltration membrane comprises a polymer or copolymer of a vinylidene difluoride monomer;

(c) separating the retentate fraction with added solvent into a secondary permeate stream and a secondary retentate stream; and

(d) evaporating solvent from the secondary retentate stream to produce a lecithin product having an acetone insoluble content of about 60 wt% to about 97 wt%.

5. The process claim 1, further comprising the step of adding soap to the oil prior to contacting the oil with the ultrafiltration membrane.

6. The process of claim 1, further comprising the step of adding a surfactant to the oil prior to contacting the oil with the ultrafiltration membrane.

7. The process of claim 1, further comprising the step of adding a polar solvent to the oil prior to contacting the oil with the ultrafiltration membrane.

8. The process of claim 7, wherein the polar solvent is selected from the group consisting of alcohol, water, and a combination of alcohol and water.

9. The process of claim 1, further comprising the step of prior to contacting the oil with an ultrafiltration membrane, forming soaps in situ by the neutralization of free fatty acids present in the oil by the addition of a base.

10. The process of claim 9, wherein the neutralization is limited to a partial neutralization.

11. The process of claim 9, wherein the base is selected from the group consisting of an hydroxide, a soluble silicate, and a combination of an hydroxide and a soluble silicate.

12. The process of claim 1, wherein the ultrafiltration membrane has a molecular weight cut-off in the range of about 5,000 daltons to about 500,000 daltons.

13. The process of claim 1, wherein the ultrafiltration membrane has a molecular weight cut-off in the range of about 10,000 daltons to about 250,000 daltons.

14. The process claim 1, further comprising the step of pre-filtering the oil prior to contacting the oil with the ultrafiltration membrane.

15. The process of claim 1, further comprising the step of at least partially degumming the oil prior to contacting the oil with the ultrafiltration membrane.

16. The process of claim 1, wherein the step of treating the retentate fraction comprises a treating process selected from the group consisting of water degumming, acid degumming, and acid refining.

17. The process of claim 1, wherein the steps are performed in a continuous process and the step of treating the retentate fraction yields a degummed retentate stream which is added to the oil prior to contact with the ultrafiltration membrane.