CONTINUOUS-FLOW DETERMINATION OF NATURAL AND SYNTHETIC ANTIOXIDANTS IN FOODS BY GAS-CHROMATOGRAPHY

A simple, rapid continuous-flow method with gas chromatographic detect ion for the simultaneous determination of natural and synthetic antiox idants (alpha-tocopherol, alpha-tocopheryl acetate, 2,6-di-tert-butyl- p-hydroxytoluene, tert-butyl-4-hydroxyanisole and tert-butylhydroquino ne) is proposed. A solid-phase extractor is coupled to the flow system to isolate antioxidants from the sample matrix. During extraction, an alytes are released from ca. 70% of the triglycerides present in fats and oils by using XAD-7 sorbent; after selective elution with 400 mu l of 2-propanol, only ca. 0.7-0.8% of total triglycerides originally pr esent in the sample remain in the final extract. XAD-7 adsorbs 70-95% of the antioxidants except BHT of which only ca. 30% is adsorbed. The proposed method is considered an effective alternative to earlier proc edures. (C) 1998 Elsevier Science B.V.