Sensory Analysis

A blotter stick is inserted into a sample bottle of oil, removed and left a few seconds in the air to mellow. Next, the stick is carefully held just under the nose without touching it. The fastest evaporating compounds will be most prevalent in the aroma of the oil at this first encounter, These are called the top notes. The oil may be smelled several times in order to get the full impression of the aroma (but in no more than 5 minutes to prevent too much of the top note dissipating).

 The stick is set aside for a short time (the amount of time depends on the volatility of the oil—how fast it evaporates), then the blotter is again smelled (without re-dipping it) to evaluate the middle or body note.

The evaluation of the bottom or dry-out note is the last step in determining the aroma profile. A fading aroma indicates the onset of the dry-out phase. This test may take place as much as a day or more after the body note evaluation with certain oils — sandalwood, for example—that have very prolonged dry-out notes.

While all oils have top, middle and bottom notes, evaporation rates of essential oils vary. The completed description of the oil is compared to the aroma specification to look for any off-aromas or inconsistencies.

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