Inside the lab: Why extraction methods matter

Picking the right extraction method for obtaining an essential oil is, well, essential. And since the method of extraction greatly impacts the quality of the oil produced, it's important to understand how the oils you purchase are processed. 

In this series, we’re going to take an in-depth look at extraction methods, minus the laboratory jargon. We’ll explain the benefits and issues that arise with each method, and what you should look for when purchasing an essential oil.

This time, we’re looking at steam distillation. 

But first, some myth-busting. 

Many essential oil lovers see the word solvent and PANIC. Customers have asked us why we use solvents in our processes because the chemicals will ruin our oils. Except, solvents aren’t always chemicals - water is the main solvent we use for dissolving materials. 

Using a solvent in extraction is purely a way to separate certain components of the substance - so we can get all the precious essential oil from it. Certain plants require specific extraction methods - for example, water distillation should be used for flowers with delicate petals, because this technique is gentler than steam. 

A simple breakdown of steam distillation

When the steam distillation process begins, the plant material is put into a container called a Still. Steam is injected into the plant material through an inlet, which converts the aroma into a vapour. 

This vapour travels into the condenser, and it drains below into a separator. The essential oil collects on top of the water, ready to be bottled up. If the essential oil is heavier, it will sink to the bottom of the water. The remaining water produced is floral water. The exact ones you can purchase, such as rose, lavender or orange blossom!

A couple of things to consider

With steam distillation, there’s less chance of spoiling the oil quality. This is a really clean process that doesn’t require additional chemicals or high temperatures, plus it won’t use as much energy as other methods. Processing essential oils with heat can be a riskier business - high temperatures can damage the components of the oil - this is known as thermal degradation. 

This approach also limits waste, especially if the original material produces floral water. Steam extracting lavender for example, produces both floral water and essential oil, so everything that comes out can be used up. However, this type of distillation does require a higher level of skill - not something you could just do for fun from home. 

So next time you’re picking an essential oil, you can rest assured that anything with ‘steam distilled’ beside it, is probably going to be a sensible choice. A good manufacturer will always be able to discuss how they extract their essential oils. 

That concludes the first part of this series - keep your eyes peeled for next month’s!