Compounds · Phenols · Heat (Maillard reaction and pyrolysis)
Creosol
Also known as 4-Methylguaiacol · 2-Methoxy-4-methylphenol — an analysis may use any of these names
Sweet smoke, tobacco, with a slight antiseptic note. Warmer than guaiacol.
- CAS
- 93-51-6
- Formula
- C8H10O2
- Molar mass
- 138.16
- Odour threshold
- 20 ppbin water
- Boiling point
- ≈ 221 °C at atmospheric pressure
For this compound the two axes sit close together. Volatility tells you whether it leaves a surface early or late; the threshold tells you how much of it the nose needs before it notices.
Where it comes from
Biosynthetic pathway: Heat (Maillard reaction and pyrolysis) — fire breaks large molecules into ones you can smell.
About the threshold figure
Moderately low. It accompanies guaiacol in every kind of wood smoke.
Published thresholds differ by several orders of magnitude, because of differences in measuring method, sample purity and panel. The figure here is an order of magnitude for relative comparison, not a measurement. We give it only for compounds where the literature broadly agrees — 52 of the 106 compounds in the library. The rest are left blank rather than guessed.
Why it sits where it does
A phenol with an extra methyl group compared with guaiacol, fourteen mass units heavier, so it boils about sixteen degrees higher.
Where else you meet it
Wood smoke, smoked meats, whisky, and some smoked teas.