It’s a compound found in all honeys in very small concentration. In active Manuka honey it is found from as low as 100 to as high as 1000 mg/kg and it is considered to give its antiseptic edge.

It was discovered in 2008, by Professor Thomas Henle of University of Dresden, Germany. He said that it is methylglyoxal that gives Manuka honey its unique properties.

Dietary methylglyoxal is resistant to heat, body fluids, light, and enzymatic activity, thus considered very stable. This is why this compound found in Manuka honey can be considered superior to the glucose oxidase enzyme, which is found in all honeys and gives the hydrogen peroxide unique activity.

The testing done for methylglyoxal is accurate, with a plus or minus 5% margin of error. The MGO™ Certification is scientific, precise, and transparent and leaves no room for misleading. It is also very easy to explain to consumers: MGO™ 100+ Manuka honey means that in 1 kg of honey there are 100 mg of methylglyoxal. And so on.

This is a licensed trademark used by those registered New Zealand-based honey producers who have signed up to a voluntary and audited quality standard administered by the UMF Honey Association (UMFHA) of New Zealand.

Dr. Peter Molan, a Senior Lecturer at the Waikato University in New Zealand, discovered the unique property in Manuka honey, the UMF rating system was developed to measure the activity level of Manuka honey by comparing it to the disinfectant phenol.

In December 2008, Dr. Peter Molan ended a 15-year relationship with the Active Manuka Honey Association (AMHA) which runs the Unique Manuka Factor test system he created. His severing of ties comes against a backdrop of industry infighting over how Manuka honey should be measured and ranked. This is according to scoop.co.nz.

In September 2013, the Ministry of Primary Industries (MPI) has developed and issued an Interim Labelling Guide for Manuka honey. Manuka Health welcomes the release of these guidelines that will provide greater confidence and certainty for consumers looking for the genuine Manuka honey. The guide is the result of nearly ten months work with scientists, industry and other stakeholders.

MPI has identified methylglyoxal (MG or MGO) as an ingredient that can be identified in labeling and marketing Manuka honey, expressed as a minimum number of mg/kg. Scientific evidence has confirmed methylglyoxal as being a key compound that occurs naturally in Manuka honey.

Current Manuka honey product labeling such as NPA/UMF 5+, 10+, etc are considered therapeutic claims. From January 2016 these will no longer be allowed under the Food Standards Code, bringing consistency to label claims based on methylglyoxal as the ingredient that sets Manuka apart from other honeys.

The UMF grading system (i.e. UMF10+) currently relates to non peroxide activity. As clarified in the guide, this is considered a therapeutic claim. The UMF Honey Association (UMFHA) is aware of this issue and we understand they are currently working to change the parameters their grading system is based on. link

The MGO Manuka honey label, as used by Manuka Health from the beginning, will remain unchanged. For more information, you can visit the Q&A page of MPI regarding Manuka honey.