Carbon isotope ratio (13C/12C) of pine honey and detection of HFCS adulteration

Carbon isotope ratio (C-13/C-12 = delta C-13) of 100 pine honey samples collected from 9 different localities by Mugla region (Turkey) in years 2006, 2007 and 2008 were investigated. The delta C-13(protein) value of honey samples ranged between -23.7 and -26.6%,, while the delta C-13(honey) value varied between -22.7 and -27 parts per thousand. For 90% of the samples, the difference in the C isotope ratio of protein and honey fraction (delta C-13(pro)-delta C-13(hon)) was -1.0 parts per thousand and/or higher. Therefore, it can be said that the generally anticipated minimum value of C isotope difference (-1.0 parts per thousand) for honey is also valid for pine honey. On the other hand, C4 sugar value (%), which was calculated from the delta C-13(pro)-delta C-13(hon) difference, was found to be linearly correlated with the amount of adulterant (HFCS) in pine honey. These results indicate that C4 sugar value is a powerful criteria for detecting HFCS adulteration in pine honey. The delta C-13(honey) and delta C-13(protein)-delta C-13(honey) values of the samples did not show any significant differences in terms of both year and locality (P > 0.05), while the delta C-13(protein) values showed significant differences due to year (P < 0.05) but not due to locality (P > 0.05). (C) 2014 Elsevier Ltd. All rights reserved.