What is the difference between a pure essential oil and a fragrance oil?

Only about four percent of the world's essential oil production is made to a therapeutic standard. The other ninety six percent is made for the flavour and fragrance industry, to go into shampoos, creams and cleaning products. Often the same plant. Completely different oil in the bottle.

Five things decide which one you end up with:

• Where the plant is grown
• Whether the botanical species is verified
• How it is cultivated
• How it is harvested
• How it is distilled

This article covers the last one, distillation, because that is where most of the difference is either made or lost.

If you have ever tasted two wines off the same grape and the same hillside and wondered how they could be so far apart, you already understand the rest of this.

Hot and fast, or low and slow?

Flavour and fragrance oils are distilled hot, under pressure and at speed. Fifteen to twenty minutes is normal, and speed suits them. The big molecules carry the broad smell and make up sixty to eighty percent of the volume, and they distil over first.

Staying in the still another ten hours returns perhaps another twenty percent by weight, and ten to a hundred times more of the distinct compounds. Fragrance houses buy on weight, so there is no commercial reason to go the extra mile.

We go the other way. Gentle steady heat, low pressure, eight to twelve hours, no rush. Far less oil per hour on the still and far more cost per bottle, and that is exactly the point. The slow run coaxes out everything the plant made, not just the loud part of it.

What the slow run keeps that the fast one throws away

Picture a gas chromatogram. It is the chart that shows every molecule inside an oil, and it is the blueprint we hold every batch against.

A few tall peaks sit at the front. Those are the major compounds by volume, the ones a fast distillation is after. Behind them runs a long tail of tiny peaks, the trace molecules. Sesquiterpenes, and in the more complex oils like myrrh, even diterpenes. That tail is the part we want. It is where the character and the complexity of a properly extracted oil live, and it is exactly what a fast run leaves behind in the vat.

Hot and fast gives you the loud molecules on their own. Sharp, strong, one note. Low and slow gives you the whole plant in the bottle, in the balance the plant made it in.

We are happy to send you this sample chromatogram if you are interested. The printed version carries more detail than we can show here. Ask us for it.

How you can smell the difference

A fast, fragrance grade oil tends to smell sharp and then sit flat. It arrives all at once and it is gone just as quickly. That strong first hit is often mistaken for quality. It is really just the big molecules arriving on their own.

A slow distilled oil is deeper, rounder and stays with you, because there is simply more of the plant in the bottle.

Once you have used a properly distilled essential oil, the fragrance grade ones smell thin and overpowering by comparison. The wine comparison holds all the way through. You will not go back.

Where to start

Every Absolute Essential oil is distilled low and slow, and every batch is held against its own gas chromatogram before it is bottled. Browse the essential oils.

This is the first in our Need to Know series, where Dr Bo Hendgen answers the questions people actually ask about how essential oils are made.

Ngā mihi
Dr Bo Hendgen DO, ND, AM