Three main classes of essential oils in blending-an over view

[Dinh xuan Ba]

Three main classes of essential oils in blending: an overview
Dinh xuan Ba

Borrowing the language of music, each essential oil is considered as a note, so the blend of essential oils is considered as the creation of a piece of music, a harmony in scents. Based on the evaporation rate, essential oils are classified into three classes: Top notes, Middle notes, Base notes in descending order of evaporation rate. For example shown in fig 1, peppermint evaporates faster than jasmine, so peppermint is classified as Top notes and jasmine is classified as Middle notes. The final product of aromatic blending is a new and creative scent, or in musical language, a concert of aromas. As the oils in this new scent evaporate, the aroma of final product will change to reflect the aroma of remaining oils, so a proper proportion between three above-mentioned notes in a final product is a delicate and essential requirement. Professional blenders suggest that the content of these three notes should be 15%-30% for Top notes, 40%-50% for Middle notes and 20%-35% for Base notes.
Essential oils that are classified as Top notes normally evaporate the quickest, usually 1-2 hours. Top notes are generally highly volatile, fast acting, give the first impression of the blend and are not very long lasting.
The bulk of essential oils are classified as Middle notes that evaporate 2-4 hours. The smells of middle notes are not always immediately evident and may take a couple of minutes to come into their own right scents.
Essential oils that are classified as Base notes that have the longest time to evaporate, some base notes can take several days to evaporate. Base notes are normally "heavy" oils and being present for a long time. Base note can slow down the evaporation process of the other oils.

Notes: Below-mentioned classification of Notes and Blending notations is for reference only (see attachement)Three%20main%20classes%20of%20essential%20oils%20in%20blending.pdf