Lipid Processing Using Critical Fluids

Authors: Eller, Fred

Submitted to: American Institute of Chemical Engineers Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 11/10/2009
Publication Date: 11/10/2009
Citation: Eller, F.J. 2009. Lipid Processing Using Critical Fluids. American Institute of Chemical Engineers Annual Meeting.

Interpretive Summary:

Technical Abstract: A lipase (Novozyme 435) interesterification of soybean oil triacylglycerides with ethyl ferulate to produce feruloylated acylglycerols has been previously been described and patented. These feruloylated acylglycerols, termed SoyScreen™, are believed to have potential as natural sunscreens and as antioxidants for the cosmetic and food industry. Critical fluid technology has been used in several ways to improve this lipid processing method. Liquid carbon dioxide (L-CO2) has been used to purify the SoyScreen™ product from the reaction mixture. Both by-product fatty acid ethyl esters (FAMEs) and unreacted ethyl ferulate are efficiently separated from the crude reaction mixture using a L-CO2 counter-current fractionation method. A method utilizing supercritical carbon dioxide in conjunction with a silica column was also developed to purify the ethyl ferulate used in this reaction to provide nearly snow-white ethyl ferulate to be used in the interesterification reaction. Partially deacylated high oleic sunflower oil (PDHOSO) has been determined to have some advantages over soybean oil as a starting material to produce feruloylated acylglycerols. The PDHOSO is produced by enzymatic propanolysis and contains a mixture of mono-, di- and triacylglcerides as well as by-product fatty acid propyl esters (FAPEs). However, before the PDHOSO can be used to produce the feruloylated acylglycerols, the FAPEs must be removed from the crude reaction mixture. Subsequently, a continuous counter-current fractionation L-CO2 method was developed to remove the by-product FAPEs from the propanolysis reaction mixture. Critical fluid technology is being studied as a potential means to enhance the synthesis of SoyScreen™ by cycling CO2 through a bed of Novozyme 435 containing triacylglycerides and ethyl ferulate. In this process, CO2 removes FAMEs from the reaction mixture and precipitates them in a reduced pressure receiver before recycling the CO2. In this manner, the by-product FAMEs are removed from the reaction mixture allowing the reaction to proceed further to the right than otherwise possible.