Manuka honey is the common name given to the mono-floral honey produced from the Leptospermum family of flowering trees and bushes.
Manuka honey has a unique ability to kill harmful bacteria, and unlike ordinary honeys, doesn't lose that capability over time.
Moreover some Manuka honeys are very effective in killing bacteria.
There are two main methods used to show the effectiveness of a particular batch or jar Manuka honey.
The latest method is based on scientific research showing that the main anti-bacterial component of Manuka honey is a naturally occurring compound called Methylglyoxal or MGO. So the rating shows how much MGO, by weight, is contained in each kilogram of honey.
A rating of 100+, for excample, indicates the honey has at least 100milligrams of MGO in every kilogram.
UMF compares Manuka honey to a standard laboratory bleach known as phenol.
(So, for example, a batch of honey rated at 10+ kills the same amount of bacteria as a 10% phenol solution).
For more information on MGO a useful start point is go to www.manukahealth.co.nz"