New Zealand ma ̄nuka honey is derived from the floral nectar of the ma ̄nuka tree (Leptospermum scoparium J.R. Forst. & G. Forst., Myrtaceae). Dihydroxyacetone (DHA), which is found in the nectar, converts to methylglyoxal in the maturing honey (Adams, Manley- Harris, & Molan, 2009). The presence of methylglyoxal imparts non-peroxide antibacterial activity to the honey, as a result of which it is highly priced on the international market; however, there are acknowledged problems with guaranteeing the monoflorality of the honey.
These problems arise in part from the need to distinguish the pollens of ma ̄nuka and ka ̄nuka (Kunzea ericoides), as they are often found growing in the same environment, and the flowering seasons may overlap to some extent. The possibility of misrepresentation of ma ̄nuka honey has promulgated the development of guidelines about the labelling of ma ̄nuka honey originating from New Zealand, but these are necessarily constrained by the limitations outlined above.Download Full Article