Skip to main content
ARS Home » Research » Publications at this Location » Publication #65111

Title: FAT CONTENT FOR NUTRITIONAL LABELING BY SUPERCRITICAL FLUID EXTRACTION AND AN ON-LINE LIPASE CATALYZED REACTION

Author
item Snyder, Janet
item King, Jerry
item Jackson, Michael

Submitted to: Analytical Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/3/1996
Publication Date: N/A
Citation: N/A

Interpretive Summary: New methods were developed to determine the nutritional fat content of meat, as defined by the Nutritional Labeling and Education Act. The methods used carbon dioxide as a dense gas and an enzyme to extract fat from meat samples and to provide the reaction for the analysis necessary for the determination. Two different systems were developed; the first system used small representative samples; values from the analyses indicated that the method was comparable to standard solvent methods. The second method was fully automated with minimal handling of the meat samples; the values determined by this method were also equivalent to traditional solvent methods. These methods eliminate the use of large quantities of solvent presently required by traditional solvent methods. Both methods were shown to be quick and easy, plus agreement of the values from both methods was good.

Technical Abstract: A method using sequential supercritical fluid extraction (SFE) and enzymatic transesterification has been developed for the rapid determination of total nutritional fat content in meat samples. SFE conditions of 2500 psi and 50 deg C were utilized to extract lipid species from the sample matrix. The enzymatic transesterification of the lipids by ymethanol was catalyzed by an immobilized lipase isolated from Candida antarctica. Conversion of the triglycerides to fatty acid methyl esters (FAMEs) was monitored by supercritical fluid chromatography (SFC), while the fatty acid content was determined by capillary gas chromatography (GC). Total fat, saturated fat, and monounsaturated fat contents were calculated from the GC data and compared to values from traditional extraction and lipid determination methods. Both off-line SFE and automated SFE, followed by on-line GC analysis using two different instruments, were utilized in this study.