## Abstract This short account describes a novel analytical technique for the determination of total, free and esterified sterols in olive oil developed in our laboratory. This methodology is based on ^1^H and ^31^P NMR spectroscopy. The latter spectroscopic analysis requires first the derivatizati
Free and Esterified Sterol Composition of Edible Oils and Fats
β Scribed by Katherine M. Phillips; David M. Ruggio; Jari I. Toivo; Molly A. Swank; Amy H. Simpkins
- Publisher
- Elsevier Science
- Year
- 2002
- Tongue
- English
- Weight
- 190 KB
- Volume
- 15
- Category
- Article
- ISSN
- 0889-1575
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β¦ Synopsis
The free and esterified sterol concentrations in 31 edible oils and fats were determined, including individual values for sitosterol, campesterol, stigmasterol, brassicasterol, D 5 -avenasterol, sitostanol, campestanol, and cholesterol. Free and esterified sterols were separated by solid-phase extraction (SPE), saponified, and quantified as trimethylsilyl ether derivatives using capillary gas-liquid chromatography. Considerable variability in the proportion of free and esterified sterols was observed among different oils and fats, with free sterols ranging from 32 to 94% of total sterols. Refining or hydrogenation tended to decrease total sterols and increase esterified sterols. Differences in total phytosterol content and the proportion of free and esterified sterols also were evident for different samples of some oils. Among four soybean oils, total phytosterols ranged from 205 to 287 mg/100 g, and free sterols constituted 68-81% of total sterols; two different shortenings differed 62% in total sterol content (185-301 mg/100 g). Such variability in phytosterol composition likely reflects differences in processing, growing season, or variety of a particular plant source.
π SIMILAR VOLUMES
A reliable method for routine use in the determination of sterols in foods is described. In the sample preparation procedure, acid hydrolysis prior to alkaline saponi"cation was used to liberate glycosidic sterols. Sterols were analyzed by capillary gas chromatography as the trimethylsilyl ether der
## Abstract The free sterols, the sterol esters and the sterol glycosides of the raw soya and corn oils as well as those of the technical lecithin and the deodorizer distillate of the latter oils were isolated by preparative TLC. The composition of each of the isolated sterol derivatives was determ
The use of infrared spectroscopy in the study of fats and oils is reviewed. The importance of the mid-infrared region in the study of lipids is shown. Di β erences between dispersive and Fourier-transform infrared techniques are commented on and the experimental methods used in the handling of oil an
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