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Lidija Svečnjak, Goran Baranović, Marko Vinceković, Saša Prđun, Dragan Bubalo and Ivana Tlak Gajger

Abstract

Although beeswax adulteration represents one of the main beeswax quality issues, there are still no internationally standardised analytical methods for routine quality control. The objective of this study was to establish an analytical procedure suitable for routine detection of beeswax adulteration using FTIR-ATR spectroscopy. For the purpose of this study, reference IR spectra of virgin beeswax, paraffin, and their mixtures containing different proportions of paraffin (5 - 95%), were obtained. Mixtures were used for the establishment of calibration curves. To determine the prediction strength of IR spectral data for the share of paraffin in mixtures, the Partial Least Squares Regression method was used. The same procedure was conducted on beeswax-beef tallow mixtures. The model was validated using comb foundation samples of an unknown chemical background which had been collected from the international market (n = 56). Selected physico-chemical parameters were determined for comparison purposes. Results revealed a strong predictive power (R2 = 0.999) of IR spectra for the paraffin and beef tallow share in beeswax. The results also revealed that the majority of the analysed samples (89%) were adulterated with paraffin; only 6 out of 56 (11%) samples were identified as virgin beeswax, 28% of the samples exhibited a higher level of paraffin adulteration (>46% of paraffin), while the majority of the analysed samples (50%) were found to be adulterated with 5 - 20% of paraffin. These results indicate an urgent need for routine beeswax authenticity control. In this study, we demonstrated that the analytical approach defining the standard curves for particular adulteration levels in beeswax, based on chemometric modelling of specific IR spectral region indicative for adulteration, enables reliable determination of the adulterant proportions in beeswax.

Open access

Cecilia Costa, Ralph Büchler, Stefan Berg, Malgorzata Bienkowska, Maria Bouga, Dragan Bubalo, Leonidas Charistos, Yves Le Conte, Maja Drazic, Winfried Dyrba, Janja Fillipi, Fani Hatjina, Evgeniya Ivanova, Nikola Kezic, Hrisula Kiprijanovska, Michalis Kokinis, Seppo Korpela, Per Kryger, Marco Lodesani, Marina Meixner, Beata Panasiuk, Hermann Pechhacker, Plamen Petrov, Eugenia Oliveri, Lauri Ruottinen, Aleksandar Uzunov, Giacomo Vaccari and Jerzy Wilde

A Europe-Wide Experiment for Assessing the Impact of Genotype-Environment Interactions on the Vitality and Performance of Honey Bee Colonies: Experimental Design and Trait Evaluation

An international experiment to estimate the importance of genotype-environment interactions on vitality and performance of honey bees and on colony losses was run between July 2009 and March 2012. Altogether 621 bee colonies, involving 16 different genetic origins of European honey bees, were tested in 21 locations spread in 11 countries. The genetic strains belonged to the subspecies A. m. carnica, A. m. ligustica, A. m. macedonica, A. m. mellifera, A. m. siciliana. At each location, the local strain of bees was tested together with at least two "foreign" origins, with a minimum starting number of 10 colonies per origin. The common test protocol for all the colonies took into account colony survival, bee population in spring, summer and autumn, honey production, pollen collection, swarming, gentleness, hygienic behaviour, Varroa destructor infestation, Nosema spp. infection and viruses. Data collection was performed according to uniform methods. No chemical treatments against Varroa or other diseases were applied during the experiment. This article describes the details of the experiment set-up and the work protocol.