Comparison of attenuated total reflection infrared spectroscopy to capillary gas chromatography for trans fatty acid determination |
| |
Authors: | M Adam M M Mossoba T Dawson M Chew S Wasserman |
| |
Affiliation: | (1) Lipton, 3701 Southwestern Blvd., 21229 Baltimore, MD;(2) Center for Food Safety and Applied Nutrition, Food and Drug Administration, 20204 Washington, DC;(3) Perdue Farms Incorporated, 21802 Salisbury, Maryland |
| |
Abstract: | Gas chromatography (GC) has been a standard analytical tool in lipid chemistry. The rapid attenuated total reflection (ATR)
infrared (IR) American Oil Chemists’ Society (AOCS) Recommended Practice (Cd 14d-97) was compared to the capillary GC AOCS Recommended Practice (Ce 1f-97) that was optimized to accurately determine total trans fatty acids on highly polar stationary phases. This comparative evaluation was validated in an independent laboratory. These
procedures were used to quantitate the total trans fatty acid levels in partially hydrogenated vegetable oils, measured as neat (without solvent) triacylglycerols (TAG) by
ATR and as fatty acid methyl ester (FAME) derivatives by capillary GC. Unlike FAME, TAG determination by ATR required no derivatization,
but samples had to be melted prior to measurement. Five blind replicates for each of three accuracy standards and three test
samples were analyzed by each technique. The GC and ATR determinations were in good agreement. Accuracy was generally high.
The ratios of ATR mean trans values (reported as percentage of total TAG) to the true values (based on the amount of trielaidin added gravimetrically)
were 0.89, 0.98, and 1.02 for accuracy standards having about 1, 10, and 40% trans levels. The corresponding GC values, determined as percentage of total FAME, were 0.98, 0.99 and 1.04. The ratios of mean
trans values determined by these techniques were ATR/GC 0.85, 1.04, and 1.01 for test samples having trans levels of about 0.7, 8, and 38%, respectively. The optimized GC procedure also minimzed the expected low bias in trans values due to GC peak overlap found with the GC Official Method Ce 1c-89. Satisfactory repeatability and reproducibility were obtained by both ATR and GC. |
| |
Keywords: | Attenuated total reflection gas chromatography infrared peer-verified study trans fatty acids |
本文献已被 SpringerLink 等数据库收录! |
|