Evaluation of Pollen and Chemical Composition of Honey Samples Sourced from Open Markets in Anambra State, Nigeria to Ascertain their Authenticity

Aims: To ascertain the predominant honey plants that served as major sources of nectar and or pollen to the honeybees and to determine the quantitative presence of some physico-chemical components of the honey samples.

Study Design: The honey samples were collected from the various locations based on purposive sampling.

Place and Duration of Study: The samples were collected from seven towns in three Local Government Areas of Anambra State as follows; Ukpor, Usumenyi and Ezinifite (Nnewi South LGA), Nnokwa, Alor and Nnobi (Idemmili South LGA) and Ezinifite (Aguata LGA) between January and April, 2013.

Methodology: The honey samples were dissolved in warm (40ºC) acidified water and subsequently subjected to acetolysis treatment. The recovered residues were suspended in glycerol-alcohol mixture in vials from where samples were collected for routine pollen count and identification. The chemical analysis was carried out according to the analysis of the Association of Official Analytical Chemists with four replicates. The pollen data were converted to percentage, while data from chemical parameters were converted to mean and standard deviation.

Results: A total of 67 pollen types belonging to 39 families were identified. The honey samples were grouped into two based on the botanical origin: three monofloral and four polyfloral honeys. The predominant honey plants include Hymenocardia acida, Combtretaceae/Melastomataceae, Lannea sp., Alchornea cordifolia and Phyllanthus muellerianus. The chemical analysis showed that the values of all the parameters (moisture, pH, Sucrose, Protein, Hydroxymethyl furfural, etc) tested were within the acceptable limits of international honey standard. However, the sum of glucose and fructose in three honey samples did not meet the 60g/100g recommended as minimum limit for blossom honeys.

Conclusion: The chemical analysis showed that the honey samples contained acceptable standard concentrations of all the physicochemical parameters (such as HMF, protein, moisture, sucrose, etc.) tested with exception of the sum of glucose and fructose which did not meet the standard in some samples. The predominant honey plants that served as sources of nectar and pollen in the to the bees include Hymenocardia acida, Lannea sp., Phyllanthus muellerianus and members of the Combretaceae/Melastomataceae families.