Poor Smoke

Poor smoke is a fault of quality rather than quantity: even a correctly judged amount of smoke spoils the product if the smoke itself is bad. It presents as acrid, sooty, bitter or sour flavours, sometimes a greasy or tarry note, and a surface colour that reads dull, grey or uneven rather than a clean amber to mahogany. The distinction from over-smoking matters, a product can carry only a light smoke and still taste unpleasant because the smoke was dirty.

The mechanism lies in how the smoke is generated. Clean smoke and dirty smoke are different mixtures of compounds, set largely by the combustion. A cool, smouldering, oxygen-starved fire burns incompletely and produces a heavy load of the harsh, acrid fractions and tar-like deposits, including the darker products of incomplete combustion, rather than the lighter phenols and carbonyls that give sweet, mild smoke. The choice of wood feeds into it: resinous softwoods such as pine and spruce carry resins that burn to sharp, sooty, sometimes turpentine-like smoke and heavier creosote deposits, which is why they are avoided in favour of hardwoods. Creosote, the tar-like deposit that builds from smouldering and resinous fires, is both a source of bitter flavour and an unwanted residue. It is worth being honest about one point: a hotter smoke-generation temperature is not automatically safer, since the carcinogenic polycyclic aromatic hydrocarbons that smoke can carry actually tend to rise at higher smoke-generation temperatures. The aim is clean, well-aired combustion of suitable wood, not simply a hotter fire.

The usual causes are a fire choked of air so it smoulders rather than burns cleanly, the wrong wood, especially resinous softwood, damp or treated wood, or a dirty smoker whose built-up residues taint fresh smoke.

**How to avoid it.** Prevention is clean combustion of the right fuel. Use seasoned hardwood, never resinous softwood or treated timber, give the fire enough air to burn cleanly rather than smoulder in an airless box, and keep the smoker clean so old deposits do not carry into new product. A thin, translucent blue smoke is the traditional sign of clean combustion; thick, white or grey billowing smoke signals the dirty, acrid kind.

**How to fix it.** As with over-smoking, remedy is limited once the flavour is in the meat. Airing can dissipate the most volatile part, but tarry, bitter compounds that have bonded to the surface cannot be cleaned off. Prevention, by managing the fire and the wood, is the real control.

Poor smoke sits on the Stairs beside over-smoking and burning. Over-smoking is too much of otherwise acceptable smoke; poor smoke is smoke that is wrong in kind; burning is heat scorching the surface. All three degrade the smoking step, but for different reasons and with different fixes.