Active Honey and ratings systems
With so many rating systems for Bio-Active honey now, figuring it all out can be a bit tricky, so I have compiled a short summary of the schemes in use and a brief description of each.
Rather than re-invent the wheel, I will include links for you to follow and get detailed scientific explanations if you feel the need.
We, at Medi-Jelly use the NPA (Non-Peroxide Activity) scale. This is an accurate scientific scale that ranks the activity of the honey due to MGO content, by comparing it’s bacteria-killing strength to that of standard Phenol solutions of varying concentrations. In this way, a 5+ NPA ratings means that the honey has the same effect on MRSA bacteria as a standard 5% Phenol solution. The same scale is used when ratings are allocated using the term UMF (Unique Manuka Factor, a trademarked and protected NZ term), ULF (Unique Leptospermum Factor, a similar scale developed in Australia). So essentially all these terms relate to the same scale, which compares honey to phenol solutions. Hence consumers can buy a product with NPA, UMF or ULF ratings of the same number and know that they have been tested and essentially are the same strength, in relation to the special effects that these leptospermum honeys all have that other honeys do not have. It has been shown that this special effect is directly related to the chemical MGO (Methylglyoxal) and so another rather direct chemical way to compare these honeys has also evolved, and that is by rating the MGO content of them in parts per million (PPM), or mg/kg. Whilst this may seem confusing, there are ways of comparing and converting between these two sets of scales as they are all essentially measuring the same thing, a copy of such a chart is included below, and a link to a converting website is also included.
NPA stands for non-peroxide activity, the property that makes bio-active (UMF, ULF, NPA or MGO rating) manuka honey special. Manuka honeys carrying only a ‘total activity’ or ‘peroxide activity’ rating do not have this special property (Usually a blend).
UMF ratings are based on NPA properties of honey. Honey with NPA ratings between 5 and 9.9 are labelled UMF 5+, honey with NPA ratings between 10.0 and 14.9 are rated UMF 10+, and so on.
MGO is methylglyoxal, sometimes referred to as MG.
Use this table to convert between manuka honey UMF, MGO and NPA ratings.
* MGO is measured as mg/kg (ppm)
** NPA is measured as % solution (%w/v) of phenol/water