Bio-reaction process and product

• US 20030044951A1
• Filed: 09/03/2002
• Published: 03/06/2003
• Est. Priority Date: 07/14/1998
• Status: Abandoned Application

• Current Assignee: Colorado State University Research Foundation (Colorado State University System)
• Original Assignee: Colorado State University Research Foundation (Colorado State University System)
• Inventors: Johnson, Donald, Schroeder, Herbert A., Henk, Linda L., Sporleder, Robert A., Tengerdy, Robert P., Szakacs, George, Linden, James C.
• Application Number:
  US10/234,966
• Publication Number:
  US 20030044951A1
• Time in Patent Office: Days
• US Class Current: 435/198
• CPC Class Codes: A23K 10/12 by fermentation of natural products, e.g. of vegetable material, animal waste material or biomass
• CPC Class Codes: A23K 10/16 Addition of microorganisms or extracts thereof, e.g. single-cell proteins, to feeding-stuff compositions A23K10/12 takes precedence
• CPC Class Codes: A23K 20/189 Enzymes
• CPC Class Codes: C12N 1/00 Microorganisms, e.g. protozoa; Compositions thereof medicinal preparations containing material from protozoa, bacteria or viruses A61K35/66, from algae A61K36/02, from fungi A61K36/06; preparing medicinal bacterial antigen or antibody compositions, e.g. bacterial vaccines, A61K39/00; Processes of propagating, maintaining or preserving microorganisms or compositions thereof; Processes of preparing or isolating a composition containing a microorganism; Culture media therefor
• CPC Class Codes: C12P 7/08 produced as by-product or from waste or cellulosic material substrate
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel

Abstract

Rural biomass and other cellulosic materials are converted to a protein-enriched animal feed supplement or to single-cell protein by a series of bio-reactions. A first stage bio-reaction is a solid substrate bio-reaction. Enzymes, such as cellulase, produced by the first-stage bio-reaction are added to a second-stage bio-reaction. Raw second-stage bio-reaction feedstock is pretreated to hydrolyze hemicellulose and/or to partially digest starch in the feedstock. In the second-stage bio-reaction, the feedstock is substantially digested and single-cell protein is harvested in an aerobic bio-reaction, while ethanol is produced in an anaerobic reaction. Alternatively, raw biomass or other cellulosic materials can be treated with organic acid (e.g. maleic acid) combined with dry steam to produce a nutritional product that can be directly used as an animal feed supplement.

Claims

1. A process for producing product enriched for one or more enzymes selected from the group cellulase, amylase, protease, or lipase

(a) providing a first-stage bio-reaction feedstock in a solid substrate bio-reaction mixture containing microbial growth nutrients, in a bio-reactor

(b) inoculating the first-stage feedstock with a culture of a microorganism capable of secreting an enzyme selected from the group cellulase, amylase, protease, or lipase thereby producing a first bio-reaction mixture

(c) incubating the first bio-reaction mixture for a time sufficient to enrich the bio-reaction mixture with said enzyme.

2. The process of claim 1 wherein the first bio-reaction feedstock comprises cereal grain.

3. The process of claim 2 wherein the cereal grain comprises spent brewer'"'"'s grain.

4. The process of claim 1 wherein the microorganism is selected from the group Trichoderma reesei, Trichoderma hamatum, Gliocladium, Aspergillis oryzae, Aspergillis niger, Rhizopus oligosporus, Rhizopus oryzae or mixtures thereof.

5. The process of claim 1 wherein the solid substrate bio-reaction mixture lacks substantial free fluid.

6. The process of claim 5 wherein the bio-reaction mixture has less than 40% dry mass content.

7. The process of claim 1 further comprising a second-stage bio-reaction to produce a nutritional product comprising the steps of

(d) pretreating a raw second-stage bio-reaction feedstock by contacting the raw second-stage feedstock with acid for a time sufficient to hydrolyze hemicellulose, to produce free lignin, and cellulose in the second-stage feedstock, then

(e) neutralizing the acid, whereby a second-stage bio-reaction feedstock is prepared

(f) combining the second stage bio-reaction feedstock with product of the first-stage bio-reaction and a second-stage bio-reaction microorganism whereby the second stage bio-reaction is initiated,

(g) incubating the second stage bio-reaction whereby a nutritional product is produced.

8. The process of claim 7 wherein the raw second-stage feedstock is pretreated with phosphoric acid.

9. The process of claim 7 wherein the raw second-stage feedstock is pretreated with organic acid.

10. The process of claim 9 wherein said organic acid is selected from the group consisting of acetic acid, oxalic acid, succinic acid and maleic acid.

11. The process of claim 7 wherein the acid is neutralized with a nitrogen-containing base.

12. The process of claim 7 wherein the raw second stage feedstock is pretreated with peracetic acid.

13. The process of claim 7 further comprising the step of inactivating microorganisms of the first stage bio-reaction product without substantially affecting the enzyme activity in the product.

14. The method of claim 7 wherein more than 30% of the dry matter of the second-stage feedstock is cellulose.

15. The method of claim 7 wherein the second-stage bio-reaction microorganism is Saccharomyces cerevisiae or Candida utilis.

16. The process of claim 15 wherein the microorganism is S. cerevisiae and the second-stage bio-reaction is anaerobic.

17. The process of claim 15 wherein the second-stage bio-reaction is aerobic and the product is single-cell protein.

18. The process of claim 1 wherein the first-stage bio-reaction feedstock is spent brewers grain.

19. The process of claim 1 further comprising a second-stage bio-reaction to produce a nutritional or ethanolic product, comprising the steps of

(d) providing a raw second-stage bio-reaction feedstock having high starch content,

(e) combining the raw second-stage feedstock with product of the first-stage bio-reaction, whereby enzymes in the first bio-reaction product act to reduce the molecular weight of starch in the raw second-stage feedstock, then

(f) contacting the second-stage feedstock containing first bio-reaction product with acid for a time sufficient to hydrolyze hemicellulose, to produce free lignin and cellulose in the second-stage feedstock, then

(g) neutralizing the acid whereby a second-stage bio-reaction feedstock containing first bio-reaction product is prepared,

(h) combining the second-stage bio-reaction feedstock containing first bio-reaction product with a second-stage bio-reaction microorganism whereby the second-stage bio-reaction is initiated,

(i) incubating the second-stage bio-reaction whereby a nutritional or ethanolic product is produced.

20. The process of claim 19 further comprising the step of heating the raw second-stage bio-reaction feedstock to a temperature sufficient to gel the starch before step (e).

21. The process of claim 20 further comprising incubating starch gel with a heat-stable amylase active at the temperature of the starch gel.

22. The process of claim 19 wherein step (i) is anaerobic whereby an ethanolic product is produced.

23. The process of claim 19 wherein step (i) is aerobic whereby a single cell protein product is produced.

24. The process of claim 19 wherein the acid of step (f) is phosphoric acid.

25. The process of claim 24 wherein the phosphoric acid is neutralized in step (g) with a nitrogen-containing base.

26. The process of claim 19 wherein the acid of step (f) is peracetic acid.

27. The process of claim 19 further comprising the step of inactivating microorganisms of the first stage bio-reaction product without substantially affecting the enzyme activity in the product.

28. The process of claim 19 wherein the second-stage bio-reaction microorganism is Saccharomyces cerevisiae or Candida utilis.

29. A process for making an animal feed comprising

(a) combining the product of claim 1 with a non-toxic preservative substance to retard spoilage, whereby a protein and enzyme-enriched material is formed

(b) mixing the product of step (a) with grain, roughage, protein supplement, and premix.

30. An animal feed made according to the process of claim 29 wherein from about 5% to 40% of the total dry weight of the feed is a bio-reaction product made according to the process of claim 18.

31. A single cell protein product made according to the process of claim 7.

32. A single cell protein animal feed supplement made according to the process of claim 17.

33. A single cell protein animal feed supplement made according to the process of claim 23.

34. A process for producing a nutritional product comprising the steps of:

(a) treating a raw feedstock or biomass with acid combined with steam for a time sufficient to hydrolyze hemicellulose and cellulose in the raw feedstock or biomass, and (b) neutralizing the acid in the reaction mix of step (a), whereby a nutritional product is prepared.

35. The process of claim 34 wherein said is organic acid.

36. The process of claim 35 wherein said organic acid is selected from the group consisting of oxalic acid, acetic acid, maleic acid, and succinic acid.

37. The process of claim 34 wherein said acid is a mixture of two or more acids.

38. The process of claim 34 wherein said biomass is selected from the group consisting of corn stover, orchard grass, sugar cane bagasse, switchgrass, guinea grass and rice straw.

39. The process of claim 34 wherein said acid is neutralized with lime.

40. The process of claim 34 wherein said steam contains less than 40% (w/w) moisture.

41. A nutritional product prepared according to the process of claim 34.