Method and system for extraction of oil from corn

• US 7,767,836 B2
• Filed: 10/12/2006
• Issued: 08/03/2010
• Est. Priority Date: 05/18/1999
• Status: Active Grant

• Current Assignee: Board of Trustees of The University of Illinois
• Original Assignee: Board of Trustees of The University of Illinois
• Inventors: Cheryan, Munir
• Primary Examiner(s): Carr; Deborah D
• Application Number:
  US11/546,770
• Publication Number:
  US 20070037993A1
• Time in Patent Office: 1,391 Days
• Field of Search: 554/8, 554/9, 554/12, 554/13, 554/14
• US Class Current: 554/13
• CPC Class Codes: A23D 9/04 Working-up
• CPC Class Codes: A23J 1/142 by extracting with organic solvents
• CPC Class Codes: A23V 2002/00 Food compositions, function of food ingredients or processes for food or foodstuffs
• CPC Class Codes: A23V 2300/34 Membrane process
• CPC Class Codes: C11B 1/00 Production of fats or fatty oils from raw materials
• CPC Class Codes: C11B 1/10 by extracting
• CPC Class Codes: C11B 1/108 after-treatment, e.g. of miscellae
• CPC Class Codes: C11B 3/008 by filtration, e.g. including ultra filtration, dialysis C11B3/005 takes precedence

Abstract

A process for removing oil from an agricultural substrate, including a dry grind corn. An ethanol solution with a concentration in the range of from about 90% to about 100% ethanol is mixed with the dry grind corn in a ratio of from about 10:1 to about 1:1 to form an extraction solution including the ethanol solution, oil, and corn solids. The extraction solution is separated into the corn solids and a filtrate, the filtrate including the ethanol solution and oil. The filtrate is membrane filtered, including nanofiltration, to restrain an oil concentrate from the filtrate and pass a permeate of the ethanol solution. The oil contained within the oil concentrate is purified.

Claims

1. A process of extracting oil from raw corn, including the steps of:

providing a reagent solution including ethanol having a concentration between 90-100%;

mixing said reagent solution with the raw corn at a temperature between 50°

C. and 90°

C. to form an extraction solution comprising ethanol and compounds from the raw corn, said compounds including extracted oil, extracted protein mixture and corn solids;

separating said extraction solution into corn solids and a filtrate, said filtrate comprising extracted oil and extracted protein compound mixture;

membrane filtering the filtrate to pass an ethanol mixture through the membrane, said ethanol mixture containing ethanol and extracted oil to thereby separate a substantial amount of said extracted protein compound mixture;

membrane filtering the ethanol mixture to restrain a substantial amount of said extracted oil for oil collection.

2. The process of claim 1 wherein said raw corn includes corn plant product.

3. The process of claim 1 wherein said raw corn comprises ground raw corn.

4. The process of claim 1 wherein said raw corn comprises ground raw corn that is formed into flakes by a process of applying pressure on said ground raw corn.

5. The process of claim 1 wherein the oil collection includes oil having a molecular weight of between 800 and 900 daltons.

6. The process of claim 1 wherein the extracted protein compound mixture includes zein protein.

7. The process of claim 1 further comprising the step of:

purifying the oil collection.

8. The process of claim 1 wherein at least a portion of the ethanol of said extraction solution is recycled ethanol that is distilled from filtration effluent.

9. The process of claim 1 wherein ethanol is the sole reagent for extracting oil from the raw corn.

10. The process of claim 1 wherein said step of separating the extraction solution into solids and filtrate includes the use of at least one of centrifugation and filtration.

11. The process of claim 1 wherein absorbed ethanol is removed from said solids after the step of separating the extraction solution into solids and filtrate.

12. The process of claim 1 wherein after the step of separating the filtrate from the extraction solution, at least a portion of said filtrate is used as a reagent solution in a subsequent repeat of said extraction process.

13. An oil product extracted from raw corn, by a process comprising the steps of:

providing the raw corn and conditioning the raw corn;

extracting oil from said raw corn by mixing an ethanol solution with the conditioned raw corn to form an extraction solution containing extracted oil and ethanol;

separating a filtrate from said extraction solution, and membrane filtering said extracted oil product from the filtrate to restrain a substantial amount of said oil by the membrane.

14. The oil product of claim 13 wherein the process further comprises:

evaporating ethanol from the extracted oil product.

15. The oil product of claim 13 wherein said conditioning includes forming particles.

16. The oil product of claim 15 further comprising:

drying the formed particles to provide dry particles.

17. The oil product of claim 13 wherein said step of conditioning includes subjecting the raw corn to a flake roll mill and drying the flakes.

18. The oil product of claim 13 wherein said raw corn includes seeds.

19. The oil product of claim 13 wherein the step of extracting oil from the raw corn includes using ethanol recycled from an extraction solution derived from the process.

20. The oil product of claim 13 wherein the raw corn includes whole kernel corn.

21. The oil product of claim 13, wherein the ethanol solution includes 90-100% ethanol (v/v).

22. The oil product of claim 13, wherein the extracting oil step is conducted at a temperature of 50-90°

C.

23. The oil product of claim 13 wherein the ethanol solution further contains isopropyl alcohol.

24. A process of extracting oil from raw corn, comprising the steps of:

providing raw corn and ethanol produced from corn product;

mixing a solution containing said ethanol with the raw corn to form an extraction solution including ethanol, extracted oil and suspended corn solids;

deriving a filtrate from said extraction solution to separate substantially all of the suspended corn solids;

membrane filtering the filtrate to restrain an extracted oil concentrate from the filtrate and passing a permeate of the ethanol solution through said membrane; and

,

purifying the extracted oil contained with the oil concentrate.

25. The process of claim 24 wherein the step of membrane filtering the filtrate includes passing the filtrate through a nanofiltration membrane with a molecular weight cut-off such that particles having a molecular weight in the range of from about 800 daltons to about 900 daltons are restrained.

26. The process of claim 24 wherein the solution includes pure ethanol.

27. The process of claim 24 wherein the solution includes ethanol and water.

28. The process of claim 24 wherein the solution includes ethanol, water and isopropyl alcohol.