Syringol
Also written 2,6-dimethoxyphenol, syringol (smoke phenol)
Quick answer
The other wood-smoke phenol, and the one closest to what people mean by the smell of smoked food. It comes from the hardwood part of lignin, which is why the choice of wood is a specification rather than a preference.
What it does
Syringol carries the sweeter, rounder, more recognisably barbecue side of smoke where guaiacol carries the medicinal and creosote side. Hardwoods — oak, beech, the fruit woods — are richer in the syringyl lignin it comes from, and softwoods are not, which is the reason smoking traditions everywhere specify a wood and generally exclude conifers. The two compounds are always present together and their ratio is what a taster is registering when one smoked thing tastes different from another.
How it behaves when cooked
Four properties of the molecule, and what they mean at the stove.
- Volatility
- moderate
- Fat solubility
- high
- Water solubility
- low
- Heat stability
- high
It behaves as guaiacol does — persistent, fat-soluble, surviving long cooking while everything around it fades — and the practical consequences are the same: a smoked spice concentrates as a dish reduces, extracts into oil readily, and taints its neighbours in a drawer. What syringol adds specifically is an explanation for a decision cooks make without knowing why. A spice smoked over oak and one smoked over mesquite carry different ratios of these two phenols, so "smoked" is not one flavour, and substituting chipotle for pimentón brings not only more heat but a different smoke.
Not present until the plant is damaged
Lignin (syringyl units)
Absent from the plant and produced by pyrolysis of the syringyl portion of lignin in the smoking wood. Hardwood lignin is rich in syringyl units and softwood lignin is not, which is why the wood is named in every serious smoking tradition and why pimentón de la Vera specifies oak.
Spices that carry it
Recorded on the compound rather than on each spice, so the two cannot disagree.
- ChipotlePrincipal component
- Smoked paprikaPrincipal component
From oak, which is specified by the protected designation.
- Black cardamomContributing component
- TsaokoContributing component
- PaprikaPresent in small amounts
Only in the smoked grades.
Not to be confused with
Compounds a reader is likely to take for this one, and why they differ.
Guaiacol
The pair. Neither occurs without the other in wood smoke and the ratio is set by the wood.
Questions this page answers
- what is syringol
- what does syringol do
- which spices contain syringol