Incense honey, which is a unique nectar honey from the Azores archipelago, should contain over 30 % of pollen grains of the incense plant (Pittosporum undulatum Vent). In this study, a real-time PCR approach using a TaqMan probe to target the ITS region of P. undulatum was developed to specifically detect and quantify incense DNA in honey. The ITS marker developed and used for authenticating incense honey, showed high specificity against several plant species, including endemic species from the Azores archipelago, and high sensitivity, down to 0.01 pg of DNA, for P. undulatum. The method was successfully applied to 22 honey samples, from which incense DNA was detected in all 9 monofloral incense honeys, and in 50 % of the multifloral samples from the Azores. Generally, the quantitative results for incense DNA were in good agreement with the melyssopalynological analysis, showing that all samples complied with their labelling, except for 2 multifloral honey samples that should have been classified as monofloral of clover and monofloral of incense.
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