DISTRIBUTION AND QUANTIFICATION OF OIL UPTAKE IN FRENCH FRIES UTILIZING A RADIOLABELED C-14 PALMITIC ACID

A novel method utilizing C-14 palmitic acid for image analysis and liq uid scintillation for quantifying oil uptake of French fries undergoin g deep-fat frying is described. Radiolabeled computerized image analys is of the fried product furnished comprehensive visual information on the distribution and localization of oil uptake which was limited to t he crust. A significant high linear correlation (R-2 = 0.977; P < 0.00 1) was found between oil uptake measured by liquid scintillation and d ifferential scanning calorimetry, and between liquid scintillation and radiolabeled imaging (R-2 = 0.861; P < 0.001). The high specificity a nd sensitivity of the method allows quantifying uptake of very low oil concentrations ranging from several milligrams. Oil quantification vi a liquid scintillation was more sensitive than image analysis and requ ires up to 3 order of magnitude lower concentration of the radiolabele d marker. The low concentration and inherent stability of the radiolab eled chemical make this technique uniquely suitable for studying oil u ptake mechanism during deep-fat frying of foodstuffs.