Systematic identification of antioxidants in lards, shortenings, and vegetable oils by thin layer chromatography

A simple and reliable method is described for rapid identification of ascorbyl palmitate, butylated hydroxyanisole, butylated hydroxytoluene, ethoxyquin, gallates (lauryl, octyl, propyl), nordihydroguaiaretic acid, 3,3'-thiodipropionic acid, tocopherol, t-butylhydroquinone, and 2,4,5-trihydroxybutyrophenone in lards, shortenings, and vegetable oils. The antioxidants are extracted with 95% methanol, concentrated under vacuum at less than or equal to 45 degrees C, and analyzed by thin layer chromatography. Three elution solvents, 2 adsorbent types, 2 visualization sprays, and UV viewing at 254 and 36 nm are used. Sunflower and corn oil samples, fortified with 100 ppm antioxidant, were analyzed to establish to validity of the method.