Extracting Essential Oils and Hydrosols
Students at Toko School in Taranaki, New Zealand, Learn Science Through Practical Distillation Project
Students at Toko School have embarked on an exciting project involving distillation, with the aim of funding a new series of investigations. Under the guidance of teacher Sue Fergus, the students have been learning practical scientific concepts hands-on, focusing on changes of states of matter, density, and the observation of evaporation and condensation processes.
The project began when the students questioned about candle scents and lavender plants. Inspired by their curiosity, the students embarked on a journey to understand the science behind essential oils and hydrosols, a journey that would lead them to learn about measurement, temperature recording, and the comparison of inputs to outputs.
The distillation process involves heating water, which creates steam that moves through plant material, picking up volatile and non-volatile compounds. The steam then moves into a condenser, where it condenses, returning to its liquid forms. The essential oil rises to the top or sinks to the bottom and is extracted, while the remaining water forms a hydrosol.
Jim Bennett of Still Valley joined the project, sharing his expertise in making essential oils and hydrosols from native and exotic plants. The students visited Pihama Lavender to learn about steam distillation and uses for lavender oil and hydrosol.
The students tested their cleaning products made from various plants (lemon, lavender, bay laurel, mint, pine, rosemary, and hinoki cypress) to determine their effectiveness at cleaning paint, crayon, and glue residue from desks. Lemon and hinoki cypress seem most effective.
The students also learned about density, with essential oils less dense than water floating on the surface of the hydrosol, and denser oils sinking below the water.
The project is part of the Curious Minds initiative, a government-funded programme that aims to engage young students in science and maths through real-world applications. The school received funding through the Taranaki pilot of the Participatory Science Platform (PSP), a program that focuses on co-created investigations connecting curriculum learning with community and environmental issues.
The distillation project at Toko School exemplifies how students incorporate science learning through practical, real-world processes, supporting engagement and deeper understanding of scientific principles by applying them to tangible tasks.
The government's national strategic plan for Science in Society, A Nation of Curious Minds - He Whenua Hihiri i te Mahara, was a government initiative jointly led by the Ministry of Business, Innovation and Employment, Ministry of Education, and Office of the Prime Minister's Chief Science Advisor. The PSP projects typically involve student-led data collection, analysis, and interpretation related to environmental monitoring, cultural heritage, or technological innovation.
For more information about PSP projects involving young students, resources from New Zealand education departments, science organizations, or platforms like the Ministry of Business, Innovation and Employment (MBIE) might offer further insight.
The article "Building science capital at Toko School" features video reflections from students, the teacher, the principal, and a parent about the learning opportunities provided through this project. The project is also covered in the 2020 article "Making scents." Read about other Taranaki Curious Minds projects in this 2020 report.
Jim Bennett, who was involved in the project, went from extracting oil and gas from the ground to extracting essential oils. Read more about him in this Stuff article. The students compared the distillation process to the water cycle, observing heat causing water to become vapour and cooling the vapour turning it back into a liquid.
The project led to the purchase of two stills and related equipment for essential oil and hydrosol production, funded by the PSP. Venture Taranaki Trust, the regional development agency for Taranaki, partnered with the Taranaki Regional Council to lead the PSP pilot in Taranaki.
Overall, the distillation project at Toko School is a great example of how participatory science initiatives in New Zealand and similar settings leverage partnerships between schools, research organizations, and communities to foster inquiry-based learning and empower students with scientific literacy and numeracy rooted in local contexts.
- In their health-and-wellness exploration, students at Toko School, under the guidance of Sue Fergus and with the expertise of Jim Bennett, have incorporated science learning by distilling essential oils, promoting a deeper understanding of essential oils, hydrosols, and changes of states of matter.
- This distillation project, part of the Curious Minds initiative, demonstrates the potential of education-and-self-development programs in New Zealand, as it fosters learners' skills in science, measurement, temperature recording, and density, while simultaneously providing real-world skills in fitness-and-exercise, such as comparing inputs to outputs and cleaning tasks.
