Manuka Honey Strength Guide

What is Manuka honey ? a brief overview

Manuka honey is produced by bees that have foraged on the flowers of Leptospermum trees, native to Australia and New Zealand. While New Zealand has just one variety of Leptospermum, Leptospermum scoparium, Australia is home to over 80 species of Leptospermum, which contributes to the smooth, pleasing flavour of Aussie Manuka. Manuka honey has been used by native Australian and Māori cultures for thousands of years and today is a widely researched honey prized for its medicinal properties. To learn more, see our Capilano Guide to Manuka honey.

There have been a number of symbols introduced to represent the activity of Manuka honey. Following is an explanation of the more commonly used activity indicators.

Non-Peroxide Activity (NPA)

In 1981, Dr Peter Molan (MBE), professor at the University of Waikato in New Zealand, researched the peroxide activity of honeys from around the world. Hydrogen peroxide is produced in honey by the activity of the enzyme glucose oxidase when it breaks down glucose.  Hydrogen peroxide in honey acts as a preservative and has antimicrobial and antibacterial activity.  This component however tends to decrease over time and is more stable at lower temperatures.  Dr Molan found that when he deliberately destroyed the in honey, only one honey maintained antibacterial activity. This activity became known as Non-Peroxide Antibacterial activity (NPA). Dr Molan went on to research this activity over many years and found that it was very stable in Manuka honey and could withstand both heat and light exposure.

Manuka honey containing Non-Peroxide Activity (NPA) is found in both Australia and New Zealand.

Unique Manuka Factor (UMF®)

In 1995, a small New Zealand bee industry group met to discuss and investigate the best way to Trademark and protect the unique antibacterial activity (NPA) that Dr Molan had found in some Manuka honeys. In 1998, Dr Molan announced that a new trademark for the Unique Manuka Factor “UMF®” had been registered for licence holders to use as a quality mark for describing the strength of activity in New Zealand Manuka honey.

Historically, UMF® was based off NPA activity, but has recently been updated to measure different compounds, and is also used as a quality mark representing quality standards, a grading system and a rating system for Manuka honey originating in New Zealand.

Unique Manuka Factor (UMF®) is a trademark registered by the UMF Honey Association of New Zealand. UMF® is only available for licensed use by UMF Honey Association of New Zealand members in relation to honey originating in New Zealand.

Methylglyoxal (MGO) – the number to look for!

More recent research has shown that one of the major components that is attributed to the unique activity in Manuka honey is Methylglyoxal (MGO) and this chemical marker is now used as the key indicator of activity strength in Manuka honey.

MGO is the bioactive chemical that directly relates to the antibacterial activity in Manuka honey, and is the most accurate way to measure the potency of Manuka honey. The MGO results from dihydroxyacetone (DHA), which occurs organically in the nectar of various Manuka flowers that grow natively in Australia.

MGO is measured in parts per million (ppm) or mg/kg and the NPA is measured as a percentage of phenol equivalent. The approximate relationship between MGO concentration and the NPA of Manuka honey is outlined below:

In Summary

‘Manuka’ (Leptospermum sp.) honey containing Methylglyoxal (MGO) and dihydroxyacetone (DHA) is found in both Australian and New Zealand Manuka Honey. MGO refers to a chemical marker found in Manuka and is now used as the key indicator of the strength of activity in the honey.