Processes for producing fermentation products
The present invention relates to processes for producing fermentation products from starch-containing material, wherein an alpha-amylase and optionally a thermostable protease, pullulanase and/or glucoamylase are present and/or added during liquefaction, wherein a cellulolytic composition is present and/or added during fermentation or simultaneous saccharification and fermentation. The invention also relates to a composition suitable for use in a process of the invention.
1. A process for producing fermentation products from starch-containing material comprising the steps of:
i) liquefying the starch-containing material at a temperature above the initial gelatinization temperature using an alpha-amylase in the presence of a protease;
ii) saccharifying the liquefied starch-containing material using a carbohydrate-source generating enzyme; and
iii) fermenting using a fermenting organism;
wherein a cellulolytic composition comprising two or more enzymes selected from the group consisting of an endoglucanase, a beta-glucosidase, a cellobiohydrolase, and a polypeptide having cellulolytic enhancing activity is present or added during fermentation or simultaneous saccharification and fermentation.
2. The process of claim 1 , wherein the pH during liquefaction is in the range of 5.0-6.5.
3. The process of claim 1 , wherein the fermentation product is ethanol.
4. The process of claim 1 , wherein the alpha-amylase is from the genus Bacillus.
5. The process of claim 4 , wherein the Bacillus stearothermophilus alpha-amylase has a double deletion of positions I181+G182 and optionally a N193F substitution, or deletion of R179+G180 (using SEQ ID NO: 1 for numbering).
6. The process of claim 1 , further wherein a glucoamylase is present and/or added during saccharification and/or fermentation.
7. The process of claim 6 , wherein the glucoamylase present and/or added during saccharification and/or fermentation is of fungal origin.
8. A process for producing fermentation products from starch-containing material, comprising the steps of:
i) liquefying the starch-containing material at a temperature above the initial gelatinization temperature using:
an alpha-amylase derived from Bacillus stearothermophilus;
a protease having a thermostability value of more than 20% determined as Relative Activity at 80° C./70° C., wherein the protease is derived from Pyrococcus furiosus or Thermoascus aurantiacus ; and
a Penicillium oxalicum glucoamylase;
ii) saccharifying the liquefied starch-containing material using a glucoamylase enzyme; and
iii) fermenting using a fermenting organism;
wherein a cellulolytic composition comprising two or more enzymes selected from the group consisting of an endoglucanse, a beta-glucosidase, a cellobiohydrolase, and a polypeptide having cellulolytic enhancing activity is present or added during fermentation or simultaneous saccharification and fermentation.
9. The process of claim 1 , wherein the cellulolytic composition is derived from a strain of Trichoderma reesei, Humicola insolens , or Chrysosporium lucknowense.
10. The process of claim 1 , wherein the cellulolytic composition is a Trichoderma reesei cellulolytic enzyme composition further comprising Penicillium emersonii GH61A polypeptide having cellulolytic enhancing activity disclosed in SEQ ID NO: 23 herein and Aspergillus fumigatus beta-glucosidase disclosed in SEQ ID NO: 22 herein or a variant thereof with the following substitutions: F100D, S283G, N456E, F512Y.
11. The process of claim 1 , wherein the pH during liquefaction is in the range of 5.0-6.0.
12. The process of claim 1 , wherein the pH during liquefaction is around 5.2.
13. The process of claim 1 , wherein the pH during liquefaction is around 5.4.
14. The process of claim 1 , wherein the pH during liquefaction is around 5.6.
15. The process of claim 1 , wherein the pH during liquefaction is around 5.8.
16. The process of claim 1 , wherein the alpha-amylase is a Bacillus stearothermophilus alpha-amylase having the amino acid sequence of SEQ ID NO: 1 or a variant thereof having at least 90% amino acid sequence identity thereto.
17. The process of claim 16 , wherein the alpha-amylase has at least 95% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 1.
18. The process of claim 16 , wherein the alpha-amylase has at least 97% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 1.
19. The process of claim 1 , wherein the protease is a variant of the metallo protease derived from a strain of Thermoascus aurantiacus.
20. The process of claim 1 , wherein the protease is derived from a strain of Pyrococcus furiosus.
21. The process of claim 1 , wherein a carbohydrate source generating enzyme is present or added during liquefaction step (i).
22. The process of claim 21 , wherein the carbohydrate source generating enzyme is a glucoamylase.
23. The process of claim 21 , wherein the carbohydrate source generating enzyme is a Penicillium oxalicum glucoamylase.
24. The process of claim 1 , wherein the cellulolytic composition is a Trichoderma reesei cellulolytic composition comprising three or more enzymes selected from the group consisting of an endoglucanase, a beta-glucosidase, a cellobiohydrolase, and a polypeptide having cellulolytic enhancing activity.
25. The process of claim 1 , wherein the cellulolytic composition is a Trichoderma reesei cellulolytic composition comprising four or more enzymes selected from the group consisting of an endoglucanase, a beta-glucosidase, a cellobiohydrolase, and a polypeptide having cellulolytic enhancing activity.
26. The process of claim 1 , wherein the starch-containing material is corn.
27. The process of claim 1 , wherein the cellulolytic composition is derived from a strain of Trichoderma reesei.
28. The process of claim 8 , wherein the starch-containing material is corn.
29. The process of claim 8 , wherein the cellulolytic composition is derived from a strain of Trichoderma reesei.
30. The process of claim 8 , wherein the fermentation product is ethanol.