Processes for producing a fermentation product

Abstract

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; 
 optionally a protease having a thermostability value of more than 20% determined as Relative Activity at 80° C./70° C.; and 
 optionally a carbohydrate-source generating enzyme; 
   ii) saccharifying using a carbohydrate-source generating enzyme;   iii) fermenting using a fermenting organism;   
       wherein a cellulolytic composition is present or added during fermentation or simultaneous saccharification and fermentation. 
     
     
         2 . The process of  claim 1 , wherein the pH during liquefaction is between above 5.0-6.5, such as above 5.0-6.0, such as above 5.0-5.5, such as between 5.2-6.2, such as around 5.2, such as around 5.4, such as around 5.6, such as around 5.8. 
     
     
         3 . The process of  claim 1 , wherein the fermentation product is an alcohol, preferably ethanol, especially fuel ethanol, potable ethanol and/or industrial ethanol. 
     
     
         4 . The process of  claim 1 , wherein the alpha-amylase is from the genus  Bacillus , such as a strain of  Bacillus stearothermophilus , in particular a variant of a  Bacillus stearothermophilus  alpha-amylase, such as the one shown in SEQ ID NO: 1 herein. 
     
     
         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 , wherein the protease is a variant of the metallo protease derived from a strain of the genus  Thermoascus , preferably a strain of  Thermoascus aurantiacus , especially  Thermoascus aurantiacus  CGMCC No. 0670. 
     
     
         7 . The process of  claim 1 , wherein the protease is derived from a strain of  Pyrococcus , preferably a strain of  Pyrococcus furiosus.    
     
     
         8 . The process of  claim 1 , wherein the carbohydrate-source generating enzyme present and/or added during liquefaction step i) is a glucoamylase, preferably derived from a strain of the genus  Penicillium , especially a strain of  Penicillium oxalicum  disclosed as SEQ ID NOs: 9 or 14 herein. 
     
     
         9 . The process of  claim 1 , further wherein a glucoamylase is present and/or added during saccharification and/or fermentation. 
     
     
         10 . The process of  claim 1 , wherein the glucoamylase present and/or added during saccharification and/or fermentation is of fungal origin, preferably from a stain of  Aspergillus , preferably  A. niger, A. awamori , or  A. oryzae ; or a strain of  Trichoderma , preferably  T. reesei ; or a strain of  Talaromyces , preferably  Talaromyces emersonii , or a strain of  Pycnoporus , or a strain of  Gloeophyllum , such as a strain of  Gloeophyllum sepiarium  or  Gloeophyllum trabeum  or a strain of the  Nigrofomes.    
     
     
         11 . The process of  claim 1 , 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;    
 optionally a protease having a thermostability value of more than 20% determined as Relative Activity at 80° C./70° C., preferably derived from  Pyrococcus furiosus  and/or  Thermoascus aurantiacus ; and 
 a  Penicillium oxalicum  glucoamylase; 
   ii) saccharifying using a glucoamylase enzyme;   iii) fermenting using a fermenting organism;   
       wherein a cellulolytic composition is present or added during fermentation or simultaneous saccharification and fermentation. 
     
     
         12 . The process of  claim 1 , wherein the cellulolytic composition is derived from a strain of  Trichoderma , in particular  Trichoderma reesei , or a strain of  Humicola , in particular  Humicola insolens , or a strain of  Chrysosporium , in particular  Chrysosporium lucknowense.    
     
     
         13 . The process of  claim 1 , wherein the cellulolytic composition is a  Trichoderma reesei  cellulolytic enzyme composition further comprising  Penicillium  emersonli 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. 
     
     
         14 . An enzyme composition comprising:
 an alpha-amylase;   optionally a protease having a thermostability value of more than 20% determined as Relative Activity at 80° C./70° C.;   optionally a pullulanase; and   a carbohydrate-source generating enzyme.   
     
     
         15 . The composition of  claim 14 , wherein the alpha-amylase is from the genus  Bacillus , such as a strain of  Bacillus stearothermophilus , in particular a variant of a  Bacillus stearothermophilus  alpha-amylase, such as the one shown in SEQ ID NO: 3 in WO 99/019467 or SEQ ID NO: 1 herein. 
     
     
         16 . The composition of  claim 14 , 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). 
     
     
         17 . The composition of  claim 14 , wherein the protease is a variant of the metallo protease derived from a strain of the genus  Thermoascus , preferably a strain of  Thermoascus aurantiacus , especially  Thermoascus aurantiacus  CGMCC No. 0670. 
     
     
         18 . The composition of  claim 14 , wherein the protease is derived from a strain of  Pyrococcus , preferably a strain of  Pyrococcus furiosus.    
     
     
         19 . The composition of  claim 14 , wherein the carbohydrate-source generating enzyme is a glucoamylase having a heat stability at 850C, pH 5.3, of at least 20%, such as at least 30%, preferably at least 35%. 
     
     
         20 . The composition of  claim 14 , wherein the carbohydrate-source generating enzyme is a glucoamylase, preferably derived from a strain of the genus  Penicillium , especially a strain of  Penicillium oxalicum  disclosed as SEQ ID NOs: 9 or 14 herein.