Alcohol product processes

Abstract

The present invention relates to processes for production of an alcohol product from granular starch comprising a pre-treatment at an elevated temperature below the initial gelatinization temperature of said granular starch followed by simultaneous saccharification and fermentation, and optionally recovery of ethanol.

1 . A process for production of an alcohol product comprising the sequential steps of:
 (a) holding a slurry comprising water and granular starch in the presence of an acid alpha-amylase and a glucoamylase at a temperature of 0° C. to 20° C. below the initial gelatinization temperature of the granular starch for a period between 5 minutes and 12 hours, and   (b) fermenting the slurry in the presence of an acid alpha-amylase, a glucoamylase and a yeast at a temperature between 10° C. and 35° C. to produce the alcohol product,   
       wherein step (a) and/or step (b) is performed in the presence of an isoamylase or pullulanase. 
     
     
         2 . The process of  claim 1 , further comprising recovering the alcohol product. 
     
     
         3 . The process of  claim 1 , wherein the alcohol product is fuel ethanol, potable ethanol and/or industrial ethanol. 
     
     
         4 . The process of  claim 1 , wherein the temperature during step (b) is between 28° C. and 35° C. 
     
     
         5 . The process of  claim 1 , wherein the pH during step (a) is in the range of 3-7. 
     
     
         6 . The process of  claim 1 , wherein the pH during step (b) is in the range of 3-7. 
     
     
         7 . The process of  claim 1 , wherein the starch slurry has 5-60% DS granular starch. 
     
     
         8 . The process of  claim 1 , wherein the granular starch is obtained from tubers, roots, stems, fruits, seeds or whole grain. 
     
     
         9 . The process of  claim 1 , wherein the granular starch is obtained from corn, cobs, wheat, barley, rye, milo, sago, cassava, manioc, tapioca, sorghum, rice or potatoes. 
     
     
         10 . The process of  claim 1 , wherein the granular starch is obtained from cereals. 
     
     
         11 . The process of  claim 1 , wherein the granular starch is obtained from dry milling or wet milling of whole grain. 
     
     
         12 . The process of  claim 1 , wherein the acid alpha-amylase and the glucoamylase are present in step (a) in a ratio of between 0.3 and 5.0 AFAU/AGU. 
     
     
         13 . The process of  claim 1 , wherein the acid alpha-amylase and the glucoamylase are present in step (b) in a ratio of between 0.3 and 5.0 AFAU/AGU. 
     
     
         14 . The process of  claim 1 , wherein the acid alpha-amylase is an acid fungal alpha-amylase. 
     
     
         15 . The process of  claim 14 , wherein the acid fungal alpha-amylase is obtained from a strain of  Aspergillus.    
     
     
         16 . The process of  claim 1 , wherein the acid alpha-amylase is an acid bacterial alpha-amylase. 
     
     
         17 . The process of  claim 16 , wherein the acid bacterial alpha-amylase is derived from a strain of  B. amyloliquefaciens, B. licheniformis , or  B. stearothermophilus.    
     
     
         18 . The process of  claim 1 , wherein the glucoamylase is obtained from a strain of  Aspergillus, Clostridium , or  Talaromyces.    
     
     
         19 . The process of  claim 1 , wherein the glucoamylase is obtained from a strain of  Aspergillus niger.    
     
     
         20 . The process of  claim 1 , wherein step (a) is performed in the presence of:
 (i) an isoamylase;   (ii) a pullulanase; or   (iii) an isoamylase and a pullulanase.   
     
     
         21 . The process of  claim 1 , wherein step (b) is performed in the presence of:
 (i) an isoamylase;   (ii) a pullulanase; or   (iii) an isoamylase and a pullulanase.   
     
     
         22 . The process of  claim 1 , wherein steps (a) and (b) are performed in the presence of:
 (i) an isoamylase;   (ii) a pullulanase; or   (iii) an isoamylase and a pullanase.   
     
     
         23 . The process of  claim 1 , further comprising performing step (a) in the presence of a cellulase, phytase and/or xylanase. 
     
     
         24 . The process of  claim 1 , further comprising performing step (b) in the presence of a cellulose, phytase and/or xylanase. 
     
     
         25 . The process of  claim 1 , wherein the period in step (a) is between 20 minutes and 1¼ hours. 
     
     
         26 . The process of  claim 1 , wherein the period in step (a) is between 20 minutes and 1 hour. 
     
     
         27 . The process of  claim 1 , wherein the period in step (a) is between 40 minutes and 1 hour. 
     
     
         28 . The process of  claim 1 , wherein the period in step (a) is between 50 minutes and 1 hour. 
     
     
         29 . The process of  claim 1 , wherein the fermentation in step (b) is for a period between 20 and 250 hours.