Abstract:This paper aims to develop a new discrimination method for the adulteration of commercial edible vegetable oils from Guangzhou market by previously-established markers of fatty acid composition and stable carbon isotope ratios. 18 vegetable oils, including camellia oil, peanut oil, sunflower oil, maize oil and olive oil were purchased from the supermarket in Guangzhou. Then, their fatty acid compositions were determined by chromatography mass spectrometry (GC-MS); the stable carbon isotope ratios (?13C) of bulk oil samples and their individual major fatty acids were determined by elemental analysis-isotope ratio mass spectrometry (EA-IRMS) and gas chromatography-isotope ratio mass spectrometry (GC-IRMS). The measured data were compared with previously-reported discrimination markers. The results indicated that the quality of the commercial vegetable oils from market was overall high, but the adulteration still occurred in 50% of the samples. Obviously, the adulteration of vegetable oils may be sensitively discriminated by the markers of stable carbon isotope ratios and fatty acid composition.
