Free Access
Volume 31, Number 6, November/December 2000
Page(s) 717 - 726
DOI: 10.1051/apido:2000156

Apidologie 31 (2000) 717-726

Adulteration of honey: relation between microscopic analysis and $\delta^{13}$C measurements

Jacob D. Kerkvlieta - Harro A.J. Meijerb

aFood Inspection Service, Region North-West, Hoogte Kadijk 401, 1018 BK Amsterdam, The Netherlands
bCentre for Isotope Research (CIO), University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands

(Received 21 June 1999; revised 3 September 2000; accepted 19 September 2000)


Upon routine microscopic analysis of some honey samples, parenchyma cells, single rings of ring vessels and epidermal cells are found. These cells originate from the sugar cane stem. We investigated whether there was a relation between these plant fragments and the $\delta^{13}$C value of honey. 17 honey samples and 6 cane sugar samples were analyzed. Microscopic analysis of the samples was done quantitatively by counting the parenchyma cells, rings, and epidermal cells present in 10 g of the sample using polarized light microscopy. Also the repeatability of the microscopic analysis was determined by calculating the standard deviation of the values from the processing and examination of 8 sub-samples from one honey sample For all honey samples in this study, it was found that if more than 150 parenchyma cells and/or 10 rings in 10 g were detected, the samples were adulterated with C4 sugars (from sugar cane or corn) according to the d13C method. Lower microscopic counts indicated honey with suspected adulteration below 7%, the limit of detection of the $\delta^{13}$C method. Overall, the microscopic procedure was a good screening method for the detection of adulteration of honey with cane sugar products.

Keywords: honey / adulteration / microscopy / cane sugar / $\delta^{13}$C

Correspondence and reprints: Jacob D. Kerkvliet

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