A Rapid Evaporative Ionization Mass Spectrometry (REIMS) method, innovatively combined with an electric soldering iron, was developed for the authentication of honey and identification of sugar adulteration by Chinese researchers in collaboration with Waters Corporation UK. Evaluation of the method was undertaken using monofloral honey (acacia, rape, chaste, jujube, citrus, medlar), syrup (corn and rice), and simulated polyfloral honey and adulterated syrup-honey samples. The classification of botanical origins of honey samples were achieved with a total correct rate of 99.66% through the proposed principal component analysis-linear discriminate analysis (PCA-LDA). The monofloral honey samples (acacia honey, chaste honey, rape honey) could be well distinguished from polyfloral honey (their binary and ternary mixtures). High-value honey (acacia honey) adulterated with low-value honey (rape honey) could be detected from the level of 40% down to 5%. C3 syrup (rice syrup) and C4 syrup (corn syrup) and their adulterated syrup-honey samples in different levels (5, 10, 15, 20, 30, 40%) were also appropriately identified in relation to the adulteration level in a near linear tendency. The detection limit can reach 5–10% adulteration level, which can meet the requirement of real adulteration identification.
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