# Mānuka honey

Mānuka honey (Māori pronunciation:) is a monofloral honey produced from the nectar of the mānuka tree, Leptospermum scoparium.
The mānuka tree is indigenous to New Zealand and some parts of coastal Australia, but mānuka honey is today produced globally. Used as a sugar substitute, it has a strong, earthy aroma and flavour. The word mānuka is the Māori name of the tree; however, as with many Māori words, the older spelling manuka (without a macron) remains relatively common in English.

## Identification

Mānuka honey is produced by European honey bees (Apis mellifera) foraging on the mānuka (Leptospermum scoparium), which evidence suggests originated in Australia before the onset of the Miocene aridity. It grows uncultivated throughout both southeastern Australia and New Zealand.
Mānuka honey is markedly viscous. This property is due to the presence of a protein or colloid and is its main visually defining characteristic, along with its typical dark cream to dark brown colour.
The mānuka tree flowers at the same time as Kunzea ericoides, another Myrtaceae species also called kānuka, which often shares the same growing areas. Some apiarists cannot readily differentiate these species, as both flowers have similar morphology and pollen differentiation between the two species is difficult.
Mānuka honey for export from New Zealand must be independently tested. The country's Ministry for Primary Industries has developed a government standard called the Mānuka Honey Science Definition test to identify that all mānuka honey is pure when it leaves the country. The test comprises five attributes, four of which are chemical, and one of which is DNA of Leptospermum scoparium. The honey must pass all five tests to be labeled as pure New Zealand mānuka. This testing came into effect on 5 January 2018. Independent quality and rating organisation, the UMF Honey Association then certifies four quality factors for honey harvested, packed, and sealed in New Zealand.
The UMF Honey Association was originally known as the Active Manuka Honey Association (AMHA), and was formed in 2002. In 2011, the AMHA became The Unique Manuka Factor Honey Association (UMFHA). The Australian Manuka Honey Association (AMHA) was established in 2017 following the discontinuation of the New Zealand Manuka Honey industry's change of the use of the acronym AMHA. They established a set of standards for authentic Australian Manuka honey. Honey that carries the AMHA's Mark of Authenticity must be pure, natural Manuka honey, produced entirely in Australia, and be tested by an independent, approved laboratory to ensure it meets minimum standards of naturally occurring methylglyoxal, dihydroxyacetone, and leptosperin.

## Food

Mānuka honey has a strong flavour, characterised as "earthy, oily, herbaceous", and "florid, rich and complex". It is described by the New Zealand honey industry as having a "damp earth, heather, aromatic" aroma and a "mineral, slightly bitter" flavour.

## Grading

In New Zealand, Mānuka honey is graded by the amount of natural signature chemicals it contains. In New Zealand, single-flower Mānuka honey is dual-graded using MGO (methylglyoxal) concentration in mg/kg and UMF (Unique Manuka Factor). Blended/multifloral Mānuka is graded using the MGS system, which has a linear relationship with MGO value but is numerically different from UMF.
In the UK, Mānuka honey is graded with MGO and NPA (non-peroxide activity). NPA measures the non-peroxide activity in the honey. The NPA is positively correlated with MGO content and is made to be numerically near-identical to the UMF.
Manuka Honey Ratings from MGO :
| MGO (mg/kg) | UMF/NPA | MGS (= 4 + MGO / 50) |
| 83 | 5 | 4.2 |
| 263 | 10 | 9.3 |
| 514 | 15 | 14.3 |
| 696 | 18 | 17.9 |
| 829 | 20 | 20.6 |
| 1122 | 24 | 26.4 |
| 1282 | 26 | 29.6 |
| 1450 | 28 | 33 |
There is also a K-Factor rating, which counts the number of pollens. It has no correlation with the concentration of any active chemical. UMF, MGS, and K-Factor all imply that the honey is genuine.

## Controversy
### Grading, counterfeit, and adulteration

As a result of the high premium paid for mānuka honey, an increasing number of products now labeled as such worldwide are adulterated or counterfeit. According to research by the Unique Mānuka Factor Honey Association (UMFHA), the main trade association of New Zealand mānuka honey producers (New Zealand being the main producer of mānuka honey in the world), while only 1,700 tonnes (3.7 million pounds) of mānuka honey are produced in New Zealand every year, six times as much are marketed internationally as mānuka honey, of which 1,800 tonnes (4.0 million pounds) are in the UK alone.
In governmental agency tests in the UK between 2011 and 2013, a majority of mānuka-labeled honeys sampled lacked the non-peroxide anti-microbial activity of mānuka honey. Likewise, of 73 samples tested by UMFHA in Britain, China, and Singapore in 2012–13, 43 tested negative. Separate UMFHA tests in Hong Kong found that 14 out of 56 mānuka honeys sampled had been adulterated with syrup. In 2013, the UK Food Standards Agency asked trading standards authorities to alert mānuka honey vendors to the need for legal compliance.
The UMFHA trademarked a honey rating system called Unique Mānuka Factor, but there is a confusing range of competing rating systems for mānuka honeys. In one UK chain in 2013, two products were labeled "12+ active" and "30+ total activity" respectively for "naturally occurring peroxide activity", and another "active 12+" for "total phenol activity", yet none of the three were labeled for the strength of the non-peroxide antimicrobial activity specific to mānuka honey.

### Crime

There have been increasing turf disputes between producers operating close to large mānuka tree clumps. Cases have been reported of many hives being variously sabotaged, poisoned, or stolen.