Lipids interesterification

Lipases are used to hydrolyse milk fat for a variety of uses in the confectionary, sweet, chocolate, sauce and snack food industries and there is interest in using immobilized lipases to modify fat flavours for such applications (Kilara, 1985). Enzymatic interesterification of milk lipids to modify rheological properties is also feasible. 

Nor Hayati, I., Aminah, A., Mamot, S., Nor Aini, I., Noor Lida, H.M., Sabariah, S. 2000. Melting characteristic and solid fat content of milk fat and palm stearin blends before and after enzymatic interesterification. J. Food Lipids. 7, 175-193. 

Rousseau, D., Marangoni, A.G. 2002. The effects of interesterification on the physical properties of fats. In, Physical Properties of Lipids (A.G. Marangoni, S.S. Narine, eds.), pp. 479-564, Marcel Dekker, New York. 

Another promising area for adaptation of enzyme bioreactor technology is that of lipid modification. Several examples are a) the interesterification of triacylglycerols to change their composition b) limited lipolysis for production of flavors and c) conversion of cholesterol to forms that are not absorbed. The potential stabilization of enzymes to the presence of organic solvents would provide a definite advantage to enzyme bioreactor technology for the modification of lipid molecules. 

The lipase-catalyzed interesterification process can be used for the production of triacylglycerols with specific physical properties, and it also opens up possibilities for making so-called structured lipids. An example is a triacylglycerol that carries an essen-... 

Chapter 4 presents the chemistry and technology of edible oil, fat, and wax processing including refining, recovery, crystallization, interesterification, and hydrogenation. The key oxidation reactions of lipids leading to quality deterioration of processed and unprocessed foods, and the mechanism of... 

Considerable recent research has defined conditions for successful use of lipases and other enzymes in numerous lipid modification reactions, including a variety of types of interesterifications (69, 71, 76). For edible applications to date, they have been employed at industrial scales for the production of (1) cocoa butter substitutes, for which disaturated, monounsaturated acylglycerols with the unsaturated fatty acid in the sn-2 position are desired (77) (2) to produce human milkfat analogues, where 2-palmitoyl acylglycerols are desired (77) (3) in the synthesis of 1,3- di-acylglycerols (78) and in the production of diacylglycerols for edible applications. These reactions employ vegetable oils as feedstocks. 

Microbial lipases may be used as biocatalysts for interesterification. Lipase-assisted interesterification offers possibilities for transformation of lipids beyond those possible using chemical interesterification (11). Enzymatic interesterihcation has several advantages over the chemical-assisted reactions, such as mild reaction conditions leading to reduced energy consumption and less thermal damage to reactants and products, the possibility of lipase specificity toward their natural substrates, as well as high catalytic efficiency. Lipase-catalyzed interesterihcation reactions, in contrast to those carried out with chemical catalysts, yield different types of products depending on the specihcity of the lipase used. 

The possible application of enzyme-assisted reactions for production of lower value nonspecialty lipids such as margarine hardstocks and cooking oils has been reported (50). When nonspecific lipases, such as those from Candida cylindraceae and C. antarctica, are used as biocatalysts for interesterification of oil blends, the TAG... 

Structured lipids (SLs) are defined as TAGs restructured or modified to change their FA composition or their positional distribution in TAG molecules by chemical or enzymatic reaction, such as direct esterification, acidolysis, alcoholysis, or interesterification, depending on the types of substrates available (Lee and Akoh, 1998). 

Xu, X. Skands, A. Jonsson, G. Adler-Nissen, J. Production of structured lipids by lipase-catalysed interesterification in an ultrafiltration membrane reactor. Biotechnol. Lett. 2000, 22 (21), 1667-1671. 

Xu, X., Balchen, S., and Adler-Nissen, J., Pilot batch production of specific-structured lipids by lipase-catalyzed interesterification preliminary study on incorporation and acyl migration, J. Am. Oil Chem. Soc., 75, 301-308, 1998. 

Xu X, Balchen S, Jonsson GA et al. (2000) Production of structured lipids by lipase-catalyzed interesterification in a flat membrane reactor. J Am Oil Chem Soc 77 1035-1041... 

Structured lipids (SL) are TAG that contain combinations of short-chain fatty acids (SCFA), medium-chain fatty acids (MCFA), and long-chain fatty acids (LCFA) located in the same glycerol molecule these may be produced by chemical or enzymatic processes (29,30). These specialty lipids may be produced via direct esterification, acidolysis, and hydrolysis or interesterification. Structured lipids are developed to fully optimize the benefits of their fatty acid varieties in order to affect metabolic parameters such as immune function, nitrogen balance, and lipid clearance from the bloodstream. 

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