In recent years there have been a growing number of scandals involving honey adulteration; seeing cheap corn syrups used to bulk out natural honey and reports of the sale of manuka honey grossly outstripping the amount actually produced. Clearly, if you don't want to be fooled, it's important to know what to look for when purchasing manuka honey.
Manuka & Geographic Origins
The first thing to know when it comes to the authenticity of manuka is that the bio-active properties are a result of the interaction between the honey bee and the nectar and pollen of Leptospermum shrub which is native to Australia & New Zealand only. However, plantations of these trees exist in other countries such as the UK, and they are absolutely capable of producing honey with the active compounds found in manuka. This then becomes an argument about the origin of the honey and whether that has an influence on its quality - this is something that requires much more research to verify.
In the case of Australia and New Zealand, a recent peer reviewed study collaborated on by Australian universities show that the honey produced from the leptospermum trees native to Australia have comparable antibacterial, antimicrobial and other active properties to those honeys produced in New Zealand (Cokcetin N. et al, 2016). ‘Manuka’ is the name that the Maori peoples of New Zealand have given to the trees. In Australia we also use this word to indicate active honey (honey with NPA activity related to MGO) made from our Leptospermum trees.
Key Active Components
Manuka honey has many health benefits which are on the cutting edge of medical and scientific research. It is being discovered that these benefits are due to the interaction of some key components that have been identified in genuine Manuka honey (Carter D. A. et al, 2016).
These components are:
- Methylglyoxal (MGO): Largely responsible for the non-peroxide activity of Manuka honey. It is measured in parts per million. The higher it is, the more therapeutic its benefits. (Carter D. A. et al, 2016, p.2)
- Dihydroxyacetone (DHA): Found in the nectar of Leptospermum and is a precursor to MGO, it converts to MGO through a natural process over time.
- Hydroxymethylfurfural (HMF): A compound that gradually forms over time as DHA is converted to MGO. It is also naturally higher in honeys that come from more tropical regions such as Australia.
- Leptosperin: A chemical marker that is characteristic of the leptospermum species (this marker guarantees authenticity but not necessarily non-peroxide activity). (Kato Y. et al, 2014)
The Australian Manuka Honey Association and the Unique Manuka Factor Association (NZ) both have their own guidelines regarding the level of key components, however, neither of them consider all four factors. Based on the current research, the interaction of all four components with each other and local factors such as environment, industry practices and regulatory standards we decided on the following standards for 1770's manuka honey:
MGO: We state the MGO on the label, so it should be equal to or more than what is stated.
DHA: ≥ 170 mg/kg at a minimum, though for the higher MGO levels we prefer the DHA levels exceed the MGO levels by around this amount so it can convert over time, maintaining the MGO level.
HMF: ≤ 50 mg/kg as Australia is a naturally warmer climate and this means naturally higher occurring HMF levels it is not usually indicative of heat mistreated honey.
Leptosperin: 50 to ≥ 100 mg/kg This varies for our manuka as those with lower MGO levels and blends, such as our anise hyssop will naturally have lower levels of Leptosperin, though we prefer it to be upwards of 100mg for our higher MGO levels.
Many people are used to seeing manuka honey as a dark, thick and viscous honey, with a deep flavour. However, these characteristics are not reliable ways to identify active, genuine manuka honey.
In reality, Australian manuka can have the colour and consistency of normal honey through to a thicker, but still ‘flowing’ consistency. It is also common in both Australia and NZ to “cream” manuka honey. This is a controlled crystallisation process that creates very small and uniform crystals in order to avoid larger, less uniform ones when the honey eventually crystallises spontaneously.* Any creamed honey will have essentially the same consistency, so if you cream a dark, regular honey, you will get something that looks exactly like the manuka most people are used to seeing. So thick consistency does not automatically equal authenticity.
What about the colour of manuka honey? Well, it can range from light pale yellows and oranges through to rich amber tones and even dark browns. It can be transparent if in its original liquid form or opaque in the case of 'creaming' or natural crystallisation. As honey naturally darkens with age, a deeper colour can suggest that a honey is a bit older and perhaps has been left to develop the MGO levels over time. However, as colour in honey is so variable and regular honey also darkens over time it is not a reliable indicator of authenticity either.
Finally, the flavour profile of manuka honey is highly dependent on the region it comes from. As Australia and NZ have very different environments and soils, you can expect each to produce honeys that also taste very different. On top of that, you also have the seasonal differences from year to year, so even honey from the same hive in the same region will taste different from harvest to harvest. Some highly active manuka can be super floral and then others can be heady and herbal, nearly earthy. I've tasted really strong and earthy manuka that was 63+ MGO right next to a light floral 500+ MGO! So although on average manuka honey does have a stronger, more complex flavour profile than regular table honey, they will each taste different to each other, so flavour is not a fool proof indicator of potency or authenticity either!
As you can probably surmise, manuka's physical characteristics are highly variable and therefore not usually good markers to use for identifying authentic manuka honey. So, what should you look for then?
We recommend you select brands with recognised testing, affiliations with regulatory bodies (such as the AMHA for Australian honey and UMF for honey from NZ) and transparent communication about their standards and practices. These are the best ways to ensure you are getting quality authentic manuka honey and enjoy exploring all the differences between them!
*If you went to know more about the crystallisation of honey and what it means - we will be doing a blog post for it soon!
Carter, D. A., Blair, S. E., Cokcetin, N. N., Bouzo, D., Brooks, P., Schothauer, R., & Harry, E. J. (2016). Therapeutic Manuka Honey: No Longer So Alternative. Frontiers in microbiology, 7, 569. doi:10.3389/fmicb.2016.00569
Cokcetin, N. N., M. Pappalardo, L. T. Campbell, P. Brooks, D. A. Carter, S. E. Blair, and E. J Harry. (2016). The Antibacterial Activity of Australian Leptospermum Honey Correlates with Methylglyoxal Levels. PLoS ONE 11.12. E0167780.
Kato, Yoji & Fujinaka, Rie & Ishisaka, Akari & Nitta, Yoko & Kitamoto, Noritoshi & Takimoto, Yosuke. (2014). Plausible Authentication of Manuka Honey and Related Products by Measuring Leptosperin with Methyl Syringate. Journal of agricultural and food chemistry. 62. 10.1021/jf501475h.