Methods and systems for producing ethanol using raw starch and fractionation

• US 8,409,639 B2
• Filed: 11/11/2010
• Issued: 04/02/2013
• Est. Priority Date: 03/10/2003
• Status: Active Grant

• Current Assignee: Poet Research Inc.
• Original Assignee: Poet Research Inc.
• Inventors: Lewis, Stephen M., Van Hulzen, Shon Erron
• Primary Examiner(s): Weber, Jon P
• Assistant Examiner(s): Srivastava, Kailash C
• Application Number:
  US12/944,618
• Publication Number:
  US 20110111085A1
• Time in Patent Office: 873 Days
• Field of Search: 426/11, 426/52, 435/14, 435/18, 435/22, 435/29, 435/96, 435/161
• US Class Current: 426/11
• CPC Class Codes: C12C 12/00 Processes specially adapted for making special kinds of beer
• CPC Class Codes: C12C 12/006 Yeasts processes for seeding C12C11/02
• CPC Class Codes: C12P 19/14 produced by the action of a carbohydrase (EC 3.2.x), e.g. by alpha-amylase , e.g. by cellulase, hemicellulase
• 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 relates to methods for producing high levels of alcohol during fermentation of plant material, and to the high alcohol beer produced. The method can include fractionating the plant material. The present invention also relates 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 method can include drying a co-product by ring drying, flash drying, or fluid bed drying. The present invention further relates to reduced stack emissions from drying distillation products from the production of ethanol.

Claims

1. A fermentation method comprising

dry fractionating plant material comprising endosperm into components including fiber, germ and endosperm;

separating the germ and fiber components of the fractionated plant material to form a remaining portion which includes the endosperm;

reducing the size of particles in the remaining portion to form a reduced portion, wherein more than 50% of the particles fit through a sieve with a 0.5 mm mesh; and

fermenting the reduced portion in a reaction mixture under acidic conditions to form a liquid comprising ethanol and a solid material, wherein the reaction mixture comprises acid stable fungal alpha amylase and yeast.

2. The method of claim 1, wherein the plant material is corn.

3. The method of claim 1, wherein the amount of said acid stable fungal alpha amylase to dry solids in said reduced portion ranges from about 0.1 to about 10 acid stable fungal alpha amylase units per gram of dry solids.

4. The method of claim 1, wherein the reaction mixture further comprises glucoamylase.

5. The method of claim 4, wherein the amount of said glucoamylase to dry solids in said reduced portion ranges from about 0.5 to about 6 glucoamylase units per gram of said dry solids.

6. The method of claim 1, wherein the acidic conditions comprise a pH of about 3 to about 6.

7. The method of claim 6, wherein the acidic conditions comprise a pH of about 4 to about 5.

8. The method of claim 1, wherein the fermentation is carried out at a temperature of about 25°

C. to about 40°

C.

9. A method of producing distiller'"'"'s dried grains (DDG) and/or distiller'"'"'s dried grains plus solubles (DDGS), the method comprising:

dry fractionating plant material comprising endosperm into components including fiber, germ and endosperm;

separating the germ and fiber components of the fractionated plant material to form a remaining portion which includes the endosperm;

reducing the size of particles in the remaining portion to form a reduced portion, wherein more than 50% of the particles fit through a sieve with a 0.5 mm mesh;

fermenting the reduced portion in a reaction mixture under acidic conditions to form a liquid comprising ethanol and a solid material, wherein the reaction mixture comprises acid stable fungal alpha amylase and yeast; and

removing the liquid comprising ethanol and drying the solid material to produce distiller'"'"'s dried grains and/or distiller'"'"'s dried grains plus solubles.

10. The method of claim 9, wherein drying the solid material is achieved with a flash or a ring dryer.

11. The method of claim 9, wherein the plant material is corn.

12. The method of claim 9, wherein the amount of said acid stable fungal alpha amylase to dry solids in said reduced portion ranges from about 0.1 to about 10 acid stable fungal alpha amylase units per gram of dry solids.

13. The method of claim 9, wherein the reaction mixture further comprises glucoamylase.

14. The method of claim 13, wherein the amount of said glucoamylase to dry solids in said reduced portion ranges from about 0.5 to about 6 glucoamylase units per gram of said dry solids.

15. The method of claim 9, wherein the acidic conditions include a pH of about 3 to about 6.

16. The method of claim 15, wherein the acidic conditions include a pH of about 4 to about 5.

17. The method of claim 9, wherein the fermentation is carried out at a temperature of about 25°

C. to about 40°

C.