Processes for the production of triglycerides of unsaturated fatty acids in the presence of enzymes

Abstract

Processes for the enzyme-catalyzed production of triglycerides using polyunsaturated fatty acids, in which (a) the reaction of polyunsaturated fatty acids and/or C 1-4 alkyl esters thereof with glycerol in vacuo in the presence of an immobilized enzyme to form their triglycerides is accelerated by addition of an additive from the group of weakly basic salts, complexing agents and ion exchangers and/or addition of a weakly basic salt and/or addition of an entraining agent in the form of a solvent or a gas and/or addition of glycerol-binding adsorbers and/or heat treatment of the partial glyceride intermediate product, (b) the immobilized enzymes are removed from the triglyceride by separation or filtration and (c) the remaining fatty acids and/or C 1-4 alkyl esters thereof are removed from the triglyceride by distillation, refining or extraction.

1 . A process comprising: 
 (a) reacting glycerol with a polyunsaturated component selected from the group consisting of polyunsaturated fatty acids, C 1-4  alkyl esters thereof and mixtures thereof, under vacuum, in the presence of an enzyme and an agent selected from the group consisting of weakly acidic salts, weakly basic salts, complexing agents, salts of complexing agents, basic ion exchangers, weakly basic ion exchangers, salts of acidic ion exchangers, solvent and gas entraining agents, glycerol-binding adsorbers, and mixtures thereof, to form a product mixture comprising (i) a triglyceride of the polyunsaturated component and (ii) one or more other components selected from the group consisting of the enzyme, the agent, unreacted polyunsaturated component, unreacted glycerol and mixtures thereof; and    (b) separating the triglyceride and the one or more other components.    
     
     
         2 . The process according to  claim 1 , wherein the polyunsaturated component comprises a compound selected from the group consisting of docosahexaenoic acid, eicosapentaenoic acid, arachidonic acid, γ-linolenic acid, linoleic acid, conjugated linoleic acid, C 1-4  alkyl esters thereof and mixtures thereof.  
     
     
         3 . The process according to  claim 1 , wherein the enzyme is immobilized on a carrier.  
     
     
         4 . The process according to  claim 1 , wherein the enzyme is selected from the group consisting of lipases, phospholipases, esterases and mixtures thereof.  
     
     
         5 . The process according to  claim 3 , wherein the enzyme is selected from the group consisting of lipases, phospholipases, esterases and mixtures thereof.  
     
     
         6 . The process according to  claim 1 , wherein the reaction is carried out under a pressure of 200 mbar or less.  
     
     
         7 . The process according to  claim 1 , wherein the agent is selected from the group consisting of weakly basic salts, salts of complexing agents, basic ion exchangers, and mixtures thereof.  
     
     
         8 . The process according to  claim 1 , wherein the agent is selected from the group consisting of weakly acidic salts, weakly basic salts, complexing agents, salts of complexing agents, basic ion exchangers, weakly basic ion exchangers, salts of acidic ion exchangers, and wherein the agent is present in an amount of from 0.001 to 5% by weight.  
     
     
         9 . The process according to  claim 1 , wherein the agent comprises a compound selected from the group consisting of sodium carbonate, sodium citrate, sodium acetate, sodium phosphate, potassium carbonate, potassium citrate, potassium acetate, potassium phosphate and mixtures thereof.  
     
     
         10 . The process according to  claim 1 , wherein the agent comprises an entraining agent which forms an azeotrope with water or short-chain alcohols.  
     
     
         11 . The process according to  claim 1 , wherein the agent comprises a glycerol-binding adsorber selected from the group consisting of silica gel, hydrophilic polymers and mixtures thereof.  
     
     
         12 . A process comprising: 
 (a) reacting glycerol with a polyunsaturated component selected from the group consisting of polyunsaturated fatty acids, C 1-4  alkyl esters thereof and mixtures thereof, under vacuum, in the presence of a first enzyme, to form an intermediate product;    (b) removing the first enzyme from the intermediate product;    (c) subjecting the intermediate product to a heat treatment to form a heat-treated intermediate product;    (d) adding a second enzyme to the heat-treated intermediate;    (e) heating the heat-treated intermediate in the presence of the second enzyme to form a product mixture comprising (i) a triglyceride of the polyunsaturated component and (ii) one or more other components selected from the group consisting of the enzyme, unreacted polyunsaturated component, unreacted glycerol and mixtures thereof; and    (f) separating the triglyceride and the one or more other components.    
     
     
         13 . The process according to  claim 12 , wherein the first enzyme and the second enzyme are the same.  
     
     
         14 . The process according to  claim 12 , wherein the polyunsaturated component comprises a compound selected from the group consisting of docosahexaenoic acid, eicosapentaenoic acid, arachidonic acid, γ-linolenic acid, linoleic acid, conjugated linoleic acid, C 1-4  alkyl esters thereof and mixtures thereof.  
     
     
         15 . The process according to  claim 12 , wherein either or both of the first enzyme and the second enzyme are immobilized on a carrier.  
     
     
         16 . The process according to  claim 12 , wherein the first enzyme and the second enzyme are selected from the group consisting of lipases, phospholipases, esterases and mixtures thereof.  
     
     
         17 . The process according to  claim 15 , wherein the first enzyme and the second enzyme are selected from the group consisting of lipases, phospholipases, esterases and mixtures thereof.  
     
     
         18 . The process according to  claim 12 , wherein the reaction is carried out under a pressure of 200 mbar or less.  
     
     
         19 . The process according to  claim 12 , wherein the heat-treatment is carried out at a temperature of from 80° C. to 160° C.  
     
     
         20 . The process according to  claim 12 , wherein the reaction of glycerol with the polyunsaturated component is carried out in the further presence of an agent selected from the group consisting of weakly acidic salts, weakly basic salts, complexing agents, salts of complexing agents, basic ion exchangers, weakly basic ion exchangers, salts of acidic ion exchangers, solvent and gas entraining agents, glycerol-binding adsorbers, and mixtures thereof.