Preparation of light stable hops

Abstract

Disclosed are methods for the production of light stable hops, useful for the brewing of beer or ale to be stored in clear or green glass containers, which beer or ale will not develop objectionable flavor as a result of exposure to light. Light stable hops are prepared by double extraction of liquid/supercritical CO 2 extracted hop solids with ethanol to remove alpha/iso-alpha-acids. Such alpha/iso-alpha-acids may be further removed from the ethanol extraction liquor obtained in the double extraction process by subjecting such liquor to an ion exchange medium, or precipitation by a metal ion, heavy metal ion, or alkali metal ion, to provide an alpha/iso-alpha-acids free extraction liquor which may be added to the light stable hops residue obtained in the initial double extraction process.

1 . A method for the preparation of a light stable hop product, the method comprising: 
 mixing hop solids with a first alcohol solvent to form a mixture of the hop solids and the first alcohol solvent, the hop solids being residue obtained by extracting hops with carbon dioxide;    separating the mixture of the hop solids and the first alcohol solvent into treated hop solids and a first filtrate including alpha/iso-alpha acids;    mixing the treated hop solids with a second alcohol solvent to form a mixture of the treated hop solids and the second alcohol solvent; and    separating the mixture of the treated hop solids and the second alcohol solvent into hop solids residues and a second filtrate including alpha/iso-alpha acids,    wherein a light stable hop product comprising the hop solids residues containing no alpha/iso-alpha acids is formed.    
   
   
       2 . The method of  claim 1 , wherein the first alcohol solvent and the second alcohol solvent are aqueous ethanol having a concentration of from 10 to 95 percent ethanol.  
   
   
       3 . The method of  claim 1 , further comprising: 
 blending the hop solids residues with a hop oil fraction to form the light stable hop product.    
   
   
       4 . The method of  claim 1 , further comprising: 
 blending the hop solids residues with a beta-acid rich fraction to form the light stable hop product.    
   
   
       5 . The method of  claim 1 , further comprising: 
 blending the hop solids residues with light stable bittering agents to form the light stable hop product.    
   
   
       6 . The method of  claim 1 , further comprising: 
 blending the hop solids residues with a member of the group consisting of a hop oil fraction, a beta-acid rich fraction, a light stable bittering agent, and mixtures thereof to form the light stable hop product.    
   
   
       7 . The method of  claim 1  further comprising: 
 contacting said first filtrate or said second filtrate with an ion exchange resin to remove alpha/iso-alpha-acids; and    blending an effluent of said ion exchange with the light stable hop product.    
   
   
       8 . The method of  claim 7  further comprising: 
 evaporating off aqueous alcohol from the light stable hop product.    
   
   
       9 . The method of  claim 7 , wherein said ion exchange resin is in its chloride, hydroxide, or acetate ion form.  
   
   
       10 . The method of  claim 7  wherein said light stable hop product is further blended with hop oil fraction.  
   
   
       11 . The method of  claim 7  wherein said light stable hop product is further blended with beta-acid rich fraction.  
   
   
       12 . The method of  claim 7  wherein said light stable hop product is further blended with light stable bittering agents.  
   
   
       13 . The method of  claim 7  wherein said light stable hop product is further blended with a member of the group consisting of hop oil fraction, a beta-acid rich fraction, a light stable bittering agent, and mixtures thereof.  
   
   
       14 . A method for the preparation of a light stable hop product, the method comprising: 
 mixing hop solids with a first alcohol solvent to form a mixture of the hop solids and the first alcohol solvent, the hop solids being residue obtained by extracting hops with carbon dioxide;    separating the mixture of the hop solids and the first alcohol solvent into treated hop solids and a first filtrate including alpha/iso-alpha acids;    mixing the treated hop solids with a second alcohol solvent to form a mixture of the treated hop solids and the second alcohol solvent; and    separating the mixture of the treated hop solids and the second alcohol solvent into hop solids residues and a second filtrate including alpha/iso-alpha acids,    wherein a light stable hop product comprising the hop solids residues is formed, and    wherein the method further comprises brewing a beverage with the light stable hop product.