Physicochemical quality indicators of honey: An evaluation in a Ukrainian socioecological gradient

Physical and chemical quality indicators of 65 polyfloral honey samples from three administrative districts of Chernivtsi region in South Western Ukraine were studied. The chosen administrative districts were Putyla (representing the 'Traditional villages' stratum), Storozhynets (the 'Intermediate' stratum) and Khotyn (the 'Intensive agriculture' stratum), which reflect a steep gradient of social and ecological conditions such as land cover and land use, level of economic development, culture and demography. The quality of honey was determined in accordance with the requirements of the Ukrainian national standard and the EU Directive relating to honey (or Codex Alimentarius Honey Standard) by using the following indicators: reducing sugars and moisture content, diastase activity, free acidity, pH, electrical conductivity, hydroxymethylfurfural (HMF) and proline content. The profile of carbohydrates was analyzed, in particular glucose, fructose, sucrose, maltose, trehalose, melezitose, raffinose. The ratio of fructose to glucose (F/G) was determined. All tested samples complied with the international standards for the mass fraction of reducing sugars, diastase activity and hydroxymethylfurfural content. For physical and chemical parameters, the studied honey samples were of high quality. The content of the reducing sugars in the honey samples varied within the range of 66.0-97.6%. The fructose content ranged from 342 to 549 mg/g, and the glucose content variation ranged within 283-517 mg/g. The average fructose/glucose ratio was 1.2 for honey samples from the three studied districts. Besides fructose and glucose, some oligosaccharides, such as maltose, trehalose and melezitose, were found in the examined honey. Melezitose was detected in the honey samples from 'Traditional village' (21 samples) and 'Intermediate' (5 samples) districts. The total variability of HMF content in the studied 65 honey samples from apiaries in the three districts of Chernivtsi region ranged from 0.19 to 30.8 mg/kg. The minimum moisture content was found to be 16.2% (in the 'Traditional village' and 'Intermediate' strata), and 22.2% was the maximum (in the 'Intermediate' stratum). Our studies have shown that free acidity of the samples varied within the range 13.5 to 58.0 meq/kg. Proline content variability for the three studied geographical areas ranged from 82.3 to 1201.2 mg/kg. The studied samples of honey had a low pH level (similar to 3.7), high content of proline (similar to 513 mg/kg) and reducing sugars (similar to 80%), which indicates its nutritional value and naturalness. Deviations from the honey standards in moisture content, acidity and electrical conductivity was revealed in 8% to 10% of all samples

Outcome of the workshop : C.S.I. Pollen – training the national agents in Graz

On 6th and 7th of February 2014, 26 researchers attended a workshop in Graz, Austria. The workshop was supported by COLOSS, the University of Graz and the Dean of the Faculty of Science. Pollen is the only source of proteins for honey bee colonies and is needed to feed brood, for organ development of adult honey bees and build-up of reserves to become long lived winter bees. All participants welcomed the initiative and agreed that the pollen nutrition of honey bees is of great importance for colony health and survival, and needs to be adequately studied. A means to study the biodiversity of pollen in the supply of honey bee colonies on a large scale is through the involvement of beekeepers as Citizen Scientists (C.S.). As beekeepers cannot perform full palynological analyses, we have developed a simple estimation of pollen diversity according to the colour of corbicular pollen pellets. This allows us to obtain information on a large number of samples, but also requires standardized protocols in all participating countries. National coordinators from the following countries agreed to conduct a common investigation in 2014 and 2015 using the protocols developed for C.S.I. Pollen in pilot studies in 2013: National coordinators of the following countries were present: Austria, Croatia , Denmark, England, France, Ireland, Italy, Netherlands, Norway, Romania, Scotland, Slovenia, Spain, Sweden, Switzerland and Wales. We will re-evaluate the protocols after one year, and also invite other countries to join. As a second step, samples collected by the beekeeper can be analysed to connect pollen diversity derived from colour differentiation of pollen pellets, to the number of plant species identified by palynological analysis. The funding for this second level investigation is to be left to the national coordinators. Traditional melissopalynological methods are not as suitable for the analysis of corbicular pollen pellets compared to honey, so standardized methods for this will be developed. The methods of sub-sampling, storage and transport need to be developed. The first level C.S. Investigations in the different countries will be coordinated and data collected for joint analyses and publication

Outcome of the workshop

On 4th and 5th of February 2014, 18 researchers from 13 countries attended the workshop in Graz, Austria. The workshop was supported by COLOSS, University of Graz, the Dean of the Faculty of Science and the Austrian Research Association. An authorized questionnaire that was drafted before the workshop was finalised during the workshop after necessary extended discussion. The questionnaire will be published on the COLOSS website to make it available to all interested countries. Deadlines and important dates for the 2014 monitoring and submission of data were established. The use of additional databases (meteorological and land use) which could be relevant for better understanding of the past and future loss data collected using the COLOSS questionnaire was explored, with input from specialists from other fields. So far only winter losses have been considered, however in southern countries summer losses appear to be more important. This issue was discussed and a decision was taken to further explore summer losses in specific southern areas ideally using a randomized approach. The general feeling was that the monitoring group currently acts as an European entity which attracts other countries, but which may require to develop a stronger European profile. For COLOSS, it would be a good initiative for similar entities to be developed independently in other continents by honey bee researchers based in those continents. Further exploration of specific requirements and conditions is needed. The issue of compliance with the EU regulations on data protection was discussed for future implementation. A jointly authored publication on winter 2012-2013 colony losses which is in press and soon to appear in the Journal of Apicultural Research was welcomed by the participants of the workshop and would be accompanied by an IBRA press release to publicise this article