|Sahle Demessie, Endalkachew
|TEMELLI, FERAL - DPT AG,FD,SCI ALBERTA,CAN
Submitted to: World Conference on Oilseed and Edible Oil Processing
Publication Type: Proceedings
Publication Acceptance Date: 10/6/1996
Publication Date: N/A
Technical Abstract: Combining supercritical fluid extraction (SFE) with reaction chemistry in dense fluids offers synthetic pathways and products not easily attained by conventional means. In this research we have utilized both supercritical and subcritical CO2 and H2O to produce esters, glycerides, interesterified oils as well as fatty acids from vegetable oil feedstocks. Enzymatic induced synthesis with the aid of Novozym 435 yields methyl esters of fatty acids at pressures up to 27.5 MPa and 60 deg C in SC-CO2. Similarly, monoglycerides at 65-85% yield, derived from olive, palm or corn oil, can be synthesized using Novozym 435 in the presence of SC-CO2 at 34.5 MPa and 50-70 deg C. Synthesis of the above moieties can be achieved by either multiple pump addition of the reactants or via extraction from the seeds. Useful glyceride mixtures can also be optimally achieved by glycerolysis of vegetable oils in the presence SC-CO2 at 20.7 MPa and 250 deg C with no catalyst and only a trace of water in a stirred reactor. These mixtures can be enriched in monoglyceride content by application of a thermal gradient fractionation column using SC-CO2. Random esterification of soybean oil with palm oil using Novozym 435 in SC-CO2 yields a triglyceride composition similar to a tub margarine, as judged from dropping point data and solid fat indices. Recent hydrolysis results in subcritical water produced fatty acids in 90%+ yield from numerous vegetable oils.