Partial interesterification of triacylglycerols

Abstract

A process for modifying a triacylglycerol stock, such as a vegetable oil stock, to better control fluidity is provided. The process includes interesterifying the triacylglycerol stock in the presence of a basic catalyst while monitoring the absorbance of the reaction mixture. A modified triacylglycerol stock produced by partial interesterification as well as plastic spreads and water-in-oil emulsions which include the partially interesterified triacylglycerol stock are also provided.

What is claimed is:  
     
         1 . A method of monitoring an interesterification reaction of a triacylglycerol stock comprising; 
 forming an interesterification mixture including a triacylglycerol stock and a basic catalyst; and    determining an absorbance of the interesterification mixture at one or more selected wavelengths.    
     
     
         2 . The method of    claim 1    comprising determining the absorbance at one or more selected wavelengths between about 300-500 nm.  
     
     
         3 . The method of    claim 1    wherein the basic catalyst comprises alkali metal alkoxide, alkali metal, alkali metal alloy, or alkali metal hydroxide.  
     
     
         4 . The method of    claim 3    wherein the alkali metal alkoxide comprises sodium methoxide, sodium ethoxide, potassium methoxide, potassium ethoxide, or a mixture thereof.  
     
     
         5 . The method of    claim 1    comprising determining the absorbance after heating the interesterification mixture for a sufficient time so that a measurable property of the mixture no longer changes with further heating.  
     
     
         6 . The method of    claim 1    wherein the triacylglycerol stock comprises a bleached triacylglycerol stock.  
     
     
         7 . The method of    claim 6    wherein the bleached triacylglycerol stock comprises a refined, bleached triacylglycerol stock.  
     
     
         8 . The method of    claim 1    wherein the an interesterification mixture includes a triacylglycerol stock which has been subjected to at least one modification process from the group consisting of refining, bleaching, deodorizing, fractionation and hydrogenation.  
     
     
         9 . A process for modifying a triacylglycerol stock comprising: 
 forming a mixture including the triacylglycerol stock and a basic catalyst;    reacting the mixture to form a partial interesterification product; and    determining an absorbance of the reacting mixture.    
     
     
         10 . The process of    claim 9    further comprising adding a quenching solution to the reacting mixture, thereby stopping the reaction.  
     
     
         11 . The process of    claim 9    wherein the triacylglycerol stock is a blend comprising a hardstock component and a softstock component.  
     
     
         12 . The process of    claim 11    wherein the hardstock component comprises a saturated fatty acid stock.  
     
     
         13 . The process of    claim 11    wherein the hardstock component comprises a hard triacylglycerol stock having an Iodine Value of no more than about 70.  
     
     
         14 . The process of    claim 11    wherein the softstock component includes a liquid oil, a lauric fat or a mixture thereof.  
     
     
         15 . The process of    claim 14    wherein the liquid oil comprises soybean oil, corn oil, rapeseed oil, sunflower oil, safflower oil, canola oil, cottonseed oil or a mixture thereof.  
     
     
         16 . The process of    claim 14    wherein the lauric fat comprises palm kernel oil, coconut oil or a mixture thereof.  
     
     
         17 . The process of    claim 9    wherein the triacylglycerol stock has a trans content of no more than about 30%.  
     
     
         18 . The process of    claim 9    wherein the partial interesterification product has a solid fat content at 40° C. of no more than about 30%.  
     
     
         19 . The process of    claim 9    comprising partially interesterifying the mixture at a temperature of about 50° C. to about 150° C.  
     
     
         20 . The process of    claim 9    comprising partially interesterifying the mixture under substantially anhydrous conditions.  
     
     
         21 . The process of    claim 9    comprising partially interesterifying a mixture of the triacylglycerol stock and a sufficient amount of the basic catalyst to form a partial interesterification product having a degree of interesterification of about 5% to about 95%.  
     
     
         22 . A method of determining the amount of a basic catalyst required to completely interesterify a triacylglycerol stock comprising the steps of: 
 (A) adding a first amount of the basic catalyst to a sample of the triacylglycerol stock to form a first catalyzed stock;    (B) allowing the first catalyzed stock to undergo an interesterification reaction until a measurable property of the triacylglycerol stock attains a constant value; and    (C) determining an absorbance of the first catalyzed stock after the measurable property has attained the first constant value;    (D) adding a second amount of the basic catalyst to a sample of the triacylglycerol stock to form a second catalyzed stock;    (E) allowing the second catalyzed stock to undergo an interesterification reaction until a measurable property of the triacylglycerol stock attains a second constant value; and    (F) determining an absorbance of the second catalyzed stock after the measurable property has attained the second constant value.    
     
     
         23 . A plastic spread comprising the partial interesterification product formed by the process of    claim 8   .  
     
     
         24 . A water-in-oil emulsion having a fat phase which comprises the partial interesterification product formed by the process of    claim 8   .  
     
     
         25 . A process for modifying a triacylglycerol stock comprising: 
 forming a mixture including the triacylglycerol stock and a basic catalyst, wherein the triacylglycerol stock includes a hardstock component and a softstock component;    reacting the mixture at a temperature of at least about 50° C. to form a partial interesterification product; and    determining an absorbance of the reacting mixture at one or more selected wavelengths between about 300-500 nm.    
     
     
         26 . A modified triacylglycerol stock produced by a process comprising the steps of: 
 forming a mixture including the triacylglycerol stock and a basic catalyst;    reacting the mixture to form a partial interesterification product; and    determining an absorbance of the reacting mixture.