Researchers at Waikato University department have discovered the source of the highly sought-after antibacterial ingredient in active manuka honey.
The head of the university's chemistry department, Associate Professor Merilyn Manley-Harris, says they have known for some time that the unique antibacterial activity of manuka honey is associated with the presence of a compound called methylglyoxal (MGO).
Beekeepers were aware that this increased during storage but until now, they did not know where it came from.
Dr Manley-Harris says a compound from the nectar converts over time, by a chemical reaction, into methylglyoxal which is associated with antibacterial activity.
Waikato University has patented a test to predict which honey will develop antibacterial activity during storage, which will be available to the bee industry within weeks.
Dr Manley-Harris says scientists are also now able to tell which trees have potential to yield nectar that is likely to produce honey that is active ingredient.