Method For Producing Ethanol Using Raw Starch

• US 20070196907A1
• Filed: 02/20/2007
• Published: 08/23/2007
• Est. Priority Date: 03/10/2003
• Status: Active Grant

• Current Assignee: Poet Research Inc.
• Original Assignee: Broin & Associates, Inc.
• Inventors: Lewis, Stephen
• Granted Patent: US 7,842,484 B2
• Time in Patent Office: Days
• US Class Current: 435/161
• CPC Class Codes: A23L 7/104 Fermentation of farinaceous cereal or cereal material; Addition of enzymes or microorganisms
• CPC Class Codes: A23L 7/20 Malt products preparation of malt for brewing C12C
• CPC Class Codes: C12P 7/06 Ethanol, i.e. non-beverage
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel

Abstract

The present invention is directed to the methods for producing high levels of alcohol during fermentation of plant material, and to the high alcohol beer produced. The present invention is also directed to methods for producing high protein distiller'"'"'s dried grain from fermentation of plant material, and to the high protein distiller'"'"'s dried grain produced. The present invention also relates to reduced stack emissions from drying distillation products from the production of ethanol.

Claims

1. A method of making an ethanol product comprising:

hydrolyzing carbohydrates under acidic conditions with acid stable fungal alpha amylase to form a hydrolyzed product; and

fermenting the hydrolyzed product to form the ethanol product.

2. The method of claim 1, wherein the acidic conditions include a pH of 4.0 to 5.0.

3. The method of claim 1, wherein the method is carried out in a fermenter comprising 30 wt % to 40 wt % dry solids.

4. The method of claim 1, wherein the acid stable fungal alpha amylase is included in an amount of from 0.1 to 10 AFAU/g of dry solids.

5. The method of claim 1, wherein hydrolyzing the carbohydrates is carried out in the presence of glucoamylase.

6. The method of claim 5, wherein the glucoamylase is included in an amount of from 0.1 to 6.0 AGU/g of dry solids.

7. The method of claim 1, wherein the ethanol product comprises ethanol and solid material.

8. The method of claim 7, wherein the solid material is separated from the ethanol product and the solid material dried to form distillers dried grain.

9. The method of claim 8, wherein the solid material is dried to form a distillers dried grain having 30 wt % to 45 wt % protein and 1 wt % to 23 wt % starch.

10. The method of claim 1, wherein the fermenting is conducted at a temperature of 25°

C. to 40°

C.

11. The method of claim 10, wherein the temperature is decreased as ethanol is produced.

12. The method of claim 2, wherein the pH is increased toward end of fermenting.

13. A method of making an ethanol product comprising:

contacting carbohydrates under acidic conditions with acid stable fungal alpha amylase and glucoamylase to form a hydrolyzed product; and

fermenting the hydrolyzed product to form the ethanol product.

14. The method of claim 13, wherein the acidic conditions include a pH of 4.0 to 5.0.

15. The method of claim 13, wherein the method is carried out in a fermenter comprising 30 wt % to 40 wt % dry solids.

16. The method of claim 13, wherein the acid stable fungal alpha amylase is included in an amount of from 0.1 to 10 AFAU/g of dry solids.

17. The method of claim 13, wherein the glucoamylase is included in an amount of from 0.1 to 6.0 AGU/g of dry solids.

18. The method of claim 13, wherein the ethanol product comprises ethanol and solid material.

19. The method of claim 18, wherein the solid material is separated from the ethanol product and the solid material is dried to form distillers dried grain.

20. The method of claim 19, wherein the solid material is dried to form a distillers dried grain having 30 wt % to 45 wt % protein and 1 wt % to 23 wt % starch.

21. The method of claim 13, wherein the fermenting is conducted at a temperature of 25°

C. to 40°

C.

22. The method of claim 21, wherein the temperature is decreased as ethanol is produced.

23. The method of claim 14, wherein the pH is increased toward end of fermenting.

24. Distillers dried grain comprising:

wt % to 45 wt % protein;

13 wt % to 17 wt % fat;

23. wt % to 37 wt % fiber; and

wt % to 23 wt % starch.

25. An animal feed comprising distillers dried grain in which the distillers dried grain includes:

wt % to 45 wt % protein;

13 wt % to 17 wt % fat;

23 wt % to 37 wt % fiber; and

wt % to 23 wt % starch.

26. A method of making an ethanol product having reduced hydrocarbon emissions, comprising:

hydrolyzing carbohydrates under acidic conditions with acid stable fungal alpha amylase to form a hydrolyzed product;

fermenting the hydrolyzed product to form the ethanol product, wherein the ethanol product comprises ethanol and solid material;

separating the solid material from the ethanol; and

drying the solid material at reduced hydrocarbon emissions rates of at least one of volatile organic compounds, carbon monoxide, nitric oxide compounds and sulfur oxides.

27. The method of claim 26, wherein the solid material is dried to produce volatile organic compounds at a rate of 1.47 lbs or less per ton of corn processed.

28. The method of claim 26, wherein the solid material is dried to produce carbon monoxide at a rate of 0.98 lbs or less per ton of corn processed.

29. The method of claim 26, wherein the acid stable fungal alpha amylase is included in an amount of from 0.1 to 10 AFAU/g of dry solids.

30. The method of claim 26, wherein hydrolyzing the carbohydrates is carried out in the presence of glucoamylase.

31. The method of claim 30, wherein the glucoamylase is included in an amount of from 0.1 to 6.0 AGU/g of dry solids.

32. A method of making an ethanol product comprising:

fractionating corn into fiber, germ, and a mixture of starch and protein;

fermenting the mixture of starch and protein under acidic conditions in the presence of acid stable fungal alpha amylase and yeast to form the ethanol product.

33. The method of claim 32, wherein the acidic conditions include a pH of 4.0 to 5.0.

34. The method of claim 32, wherein the method is carried out in a fermenter comprising 30 wt % to 40 wt % dry solids.

35. The method of claim 32, wherein the acid stable fungal alpha amylase is included in an amount of from 0.1 to 10 AFAU/g of dry solids.

36. The method of claim 32, wherein fermentation is carried out in the presence of glucoamylase.

37. The method of claim 36, wherein the glucoamylase is included in an amount of from 0.1 to 6.0 AGU/g of dry solids.

38. The method of claim 32, wherein the ethanol product comprises ethanol and solid material.

39. The method of claim 38, wherein the solid material is separated from the ethanol product and the solid material dried to form distillers dried grain.

40. The method of claim 39, wherein the solid material is dried to form a distillers dried grain having 30 wt % to 45 wt % protein and 1 wt % to 23 wt % starch.

41. The method of claim 32, wherein fermenting is conducted at a temperature of 25°

C. to 40°

C.

42. The method of claim 41, wherein the temperature is decreased as ethanol is produced.

43. The method of claim 33, wherein the pH is increased toward end of fermenting.

44. A method of making an ethanol product in multiple vessels, comprising:

hydrolyzing carbohydrates under acidic conditions with acid stable fungal alpha amylase to form a hydrolyzed product; and

fermenting the hydrolyzed product to form a fermented mixture containing the ethanol product, wherein at least a portion of the fermented mixture is drawn from a bottom portion of a first vessel and fed to a top portion of a second vessel.

45. The method of claim 44, wherein each vessel is in series.

46. The method of claim 44, wherein each vessel is in series and each subsequent vessel is fed from a prior fermenter.

47. The method of claim 44, wherein the acidic conditions include a pH of 4.0 to 5.0.

48. The method of claim 44, wherein the acid stable fungal alpha amylase is included in an amount of from 0.1 to 10 AFAU/g of dry solids.

49. The method of claim 44, wherein hydrolyzing the carbohydrates is carried out in the presence of glucoamylase.

50. The method of claim 49, wherein the glucoamylase is included in an amount of from 0.1 to 6.0 AGU/g of dry solids.

51. The method of claim 44, wherein glucose is maintained at levels at or below 3 wt %.

52. The method of claim 44, wherein maltose is maintained at levels at or below 0.34 wt %.

53. The method of claim 44, wherein maltotriose is maintained at levels at or below 0.25 wt %.

54. The method of claim 44, wherein dextins are maintained at levels at or below 0.3 wt %.

55. The method of claim 44, wherein lactic acid is maintained at less than 0.45 percent.

56. The method of claim 44, wherein acetic acid is maintained at less than 0.18 percent.