Hello Mr. Tisserand,
I am curious about re-distilled peppermint.
Someone wrote me recently and said that there was no such thing as a re-distilled peppermint. I’d like to know if this is true.
A few essential oils are ‘rectified’. Because this is also described as “re-distilled” it has given rise to the myth that many essential oils are distilled more than once – 1st, 2nd and 3rd grades, or distillations. But, once plant material has been distilled, it contains no essential oil – it is never re-distilled.
Rectification involves fractional distillation in order to remove unwanted constituents. The essential oil is put through a second process using a tall, narrow column. In the case of bitter almond oil, hydrocyanic acid (cyanide) is removed, as it is highly toxic. In peppermint, minor sulfur constituents are removed as they impart a slightly unpleasant taste, and most peppermint oils are used in food flavoring.
Two essential oils – camphor and ylang-ylang – undergo a separation process during distillation, so there are five grades of yang-ylang oil (extra, I, II, III and complete), and four colors of camphor oil (white, blue, yellow, brown)! But none of this involves re-distillation.
So yes, there is such a thing as re-distilled peppermint, but it’s the oil that’s re-processed, not the plant. Strictly speaking it is less natural, as something that was naturally there has been removed. In the case of bitter almond oil, no-one is complaining.