Sugar adulteration using carbon isotope ratio analysis by mass spectrometry is well established, but it can only be used for C4 sugar (from cane or maize) adulteration. Although a method has been developed to determine C3 sugar (from beet, most fruits or wheat) adulteration using hydrogen/deuterium isotope ratio analysis by mass spectrometry, it requires very time consuming chemical derivative preparation. The established method for C3 sugar determination has been quantitative deuterium nuclear magnetic resonance (2H NMR) measurement of ethanol derived from the sugars in the sample, which again is time consuming, and requires a normalisation process to compensate for the deuterium content of the fermentation water. Researchers at IAEA have developed a rapid method for both C3 and C4 sugar detection, which derivatises the carbohydrate's exchangeable hydroxyl-hydrogens, so that the derivative compound is sufficiently volatile to be separated and measured by a gas chromatograph coupled to an isotope ratio mass spectrometer. Feasibility of the method has been shown by measuring sugars from fruit juice and honey, but further work is required to assess the reproducibility of this method and establish its applicability for detection of undeclared addition of exogenous sugars and syrups to a range of other foods and beverages. .
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