Published: 26 Jul 2021
TIA research to help Tasmania’s essential oil industry understand how to sustainably increase yield and quality to support the market demand for Kunzea.
A research project from the Tasmanian Institute of Agriculture (TIA) will help Tasmania’s essential oil industry meet the growing demand for the endemic kunzea ambigua essential oil.
PhD student, Chanjoo Park, is investigating wild kunzea samples throughout Tasmania to identify superior cultivars for commercial propagation to meet the needs of the domestic and international market.
Ms Park has focused on agronomic techniques and how these could be adapted to produce more of the much-sought-after bioactive kunzea oil at a consistently high quality.
Kunzea essential oil has been recognised by the Australian Therapeutic Goods Administration (TGA) as having the ability to provide temporary relief of the pain of arthritis, rheumatism, muscular aches and pains, insect bites, and cold and flu symptoms.
Project Supervisor, Dr Sandra Garland said that project partners, Essential Oils of Tasmania Pty Ltd (EOT), will use the selected cultivars of kunzea ambigua to plant out on a commercial scale.
The plants were collected from the wild under the authority of permits issued by DIPWE. These were propagated and grown under ideal conditions for one year to exclude the variations from different environmental factors, including plant age.
“In this way we can compare plants equally and choose the individuals that have a high oil yield and are bioactive and fragrant” said Project Supervisor, Dr Sandra Garland.
“We’re then going to be setting up a trial site with EOT, who will plant out an area at their site in Margate”.
The collection will allow EOT to selectively crossbreed superior plants and allow for the propagation of varieties that have different aroma and chemical profiles.
“Ultimately, the viability of this new crop will require the development of elite varieties to establish commercial plantations and provide a consistent, reliable source of Kunzea oil.”
TIA’s research will help Tasmania’s essential oil industry understand how to sustainably increase yield and quality to support the markets high demand for the unique Tasmanian oil and ensure viability for the industry long term.
“Internationally, there’s a big demand for kunzea,” Chanjoo Park said.
“The limited production and high market demand make these products highly valued and, therefore, there is an imperative to improve the oil yield. The quantity available can be affected by nutrients, type of cultivar, seasonal variation and even the pruning style,” Ms Park said.
Throughout her project, Ms Park investigated harvest intensities and season which could influence oil yield and chemical constituents of kunzea oil.
The study found that plants should be left as low shrubs and harvested in autumn for improved bioactivity. Specifically, the recovery of biomass post -harvest is optimised by shallow-cut harvests, leaving sufficient resources for both vegetative growth and essential oil biosynthesis.
On a research trip to Flinders Island, Ms Park met with EOT’s industry partners and major kunzea oil producers Steve and Ben Backhaus of Bush Pharmacy. Flinders Island boasts abundant growth of the hearty wild kunzea, with trees even growing in harsh conditions on Mt Killiecrankie.
During the trip, fresh kunzea oil was collected for storage stability trials and wild kunzea samples provided new specimens to add to the collection.
“Using some freshly extracted kunzea oil from the Bush Pharmacy distillery, I was able to investigate different storage conditions over time. The results from this experiment will be helpful for industry who may be concerned about how storage affects the quality of the oil,” Ms Park said.
Ms Park said that once her project is finished, further research will be needed to help control the quality of the Kunzea oil, such as the establishment of a quality standard which specifies the levels of oil components that should be present in an authentic Tasmanian product. This is like the standards set for the Australian native Tea Tree Oil.
“Although EOT is already producing a consistent product to meet the needs of customers, standardisation of Kunzea oil would help strengthen the market competitiveness of the Tasmanian kunzea oil among essential oils domestically as well as internationally,” she said.
The popularity of kunzea oil has increased dramatically in recent years as it is used in many Australian anti-inflammatory creams and balms, soaps, and body sprays.
The topical benefits of Tasmania’s native kunzea ambigua have been understood by Tasmanian Aboriginal communities for thousands of years.
This project is part of an MoU facilitated by Professor Dugald Close to formalise the relationship between TIA and Essential Oils of Tasmania with the aim to boost research for the Tasmanian essential oil and plant extracts industry.
Ms Park is finalising the results of her study which is close to completion.