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Use of magnetic resonance procedures for measurement of oil in French-style dressings
- Heil, J.R., Perkins, W.E., McCarthy, M.J.
- Journal of food science 1990 v.55 no.3 pp. 763-884
- salad dressings, image analysis, nuclear magnetic resonance spectroscopy
- Magnetic resonance imaging and spectroscopy techniques have been developed for measuring percentage of edible oil in French-style salad dressings. In imaging, one takes advantage of the variations in signal intensities related to differences in relaxation times of the oil and aqueous phases, and of the proportionality of projected frequencies to spatial distribution of sample constituents. In spectroscopy, percentage of oil is determined from standard curves where the integrals of oil/total spectra are correlated to known amounts of oil in standard preparations. Both procedures permit rapid, nondestructive analysis of commercially packaged dressings in unopened bottles with nonmagnetic closures. Results obtained in imaging or by NMR spectroscopy were within +/- 2% of the expected values.