Submitted to: Pittsburgh Conference
Publication Type: Abstract Only
Publication Acceptance Date: March 8, 1996
Publication Date: N/A
Technical Abstract: The analysis of fat content in foods, according to the new NLEA protocols, requires an efficient, accurate, and precise extraction method for the removal of all nutritional contributing lipids from the food matrix. We have investigated the modification of an SFE procedure for extracting and quantifying fat in meat products, initially using off-line SFE accompanied by acid hydrolysis, followed by the development of an off-line SFE in-situ hydrolysis method, catalyzed by lipase in the extraction cell to yield fatty acid methyl esters (FAMES); and finally, an automated on-line SFE-SFR (supercritical fluid reaction)-GC method for total, saturated, and monounsaturated fat analysis. This lipid precipitate, from the acid hydrolysis, is isolated for SFE with the aid of an Empore filter disk, while lipase-based FAME conversion was affected by employing an immobilized enzyme of Candida antarctica in the extraction cell. Off-line SFE, using an acid hydrolysis for sample pretreatment, yielded equivalent results to conventional solvent extraction-based methods for different types of homogenized meat samples having a fat content ranging from 10-40 wt.%. The off-line method, employing enzymatic catalysis to form the FAMES, yielded good agreement with fat assays performed, using conventional solvent extractions, although the relative standard deviations of the SFE assays tended to be somewhat higher than the conventional method, due to small sample sizes employed. Results from a peer-verified study of the off-line, acid hydrolyzed sample method, using commercial SFE equipment, will conclude the presentation.