Smoking (cooking)

Smoking food—typically meat, fish, or tea—involves exposing it to smoke from smoldering material, most often wood, to add flavor, brown it, cook it, or help preserve it. The technique likely goes back to the Paleolithic era. Eventually, people began pre-curing food in salt or salty brine before smoking, creating a highly effective preservation method that many cultures around the world adopted and refined.

In Europe, alder was the traditional wood for smoking, though oak is now more common, with beech used less frequently. North American smokers often use hickory, mesquite, oak, pecan, alder, maple, and fruit woods like apple, cherry, and plum. Other materials can also be burned for smoke, sometimes with added flavorings. For example, Chinese tea-smoking heats a mix of uncooked rice, sugar, and tea at the bottom of a wok. Some North American ham and bacon makers use burning corncobs. Peat is burned to dry and smoke barley malt for Scotch whisky and certain beers. In New Zealand, sawdust from the native mānuka (tea tree) is common for hot-smoking fish, while in Iceland, dried sheep dung is used to cold-smoke fish, lamb, mutton, and whale.

Historically, Western farms had a smokehouse—a small building, set apart from other structures due to fire risk and smoke, where meat could be smoked and stored. Smoking food may introduce polycyclic aromatic hydrocarbons, which some studies link to an increased cancer risk, though this connection is debated.

Food can be smoked cold, warm, or hot. These methods primarily affect the food’s surface and cannot preserve it on their own, so smoking is combined with other microbial hurdles, like chilling and packaging, to extend shelf life. A smoke-like flavor can also be added through products such as liquid smoke.

Cold smoking keeps temperatures between 20 and 30 °C (68–86 °F), so the food remains raw and moist while absorbing smoke flavor. Because it doesn’t cook, meats must be fully cured beforehand. Cold smoking can enhance items like cheese, nuts, and various meats, which are often hung to develop a pellicle first and may be smoked for several days. Some cold-smoked foods are later baked, grilled, steamed, roasted, or sautéed. The US National Center for Home Food Preservation advises against attempting cold smoking of meats at home due to inherent risks, recommending it only for personnel certified in HACCP.

Warm smoking exposes food to temperatures of 25–40 °C (77–104 °F). Hot smoking, in a smoker oven or smokehouse, both cooks and flavors the food at temperatures usually between 52 and 80 °C (126–176 °F). The food may be hung to form a pellicle, then smoked for one to 24 hours. Hot-smoked foods are typically safe to eat without further cooking, though they are often reheated. Above 85 °C (185 °F), foods can shrink excessively, buckle, or split, and yield decreases as moisture and fat cook away.

Liquid smoke, made from smoke compounds dissolved in water, is applied by spraying or dipping. Smoke-roasting combines roasting and smoking, often called barbecuing or pit-roasting. This method can be done in a smoke-roaster, a closed wood-fired oven, a barbecue pit, or any smoker reaching above 121 °C (250 °F), or even in a conventional oven with a pan of smoldering hardwood chips. In North America, it is commonly referred to as barbecuing, pit baking, or pit roasting.

The modern era changed smoking’s purpose. With better transportation, the need for heavy salting and long smoking times to preserve food declined, and smoking became more about flavor. In 1939, the Torry Kiln was invented at the Torry Research Station in Scotland, allowing uniform mass-smoking and serving as the prototype for all modern large-scale commercial smokers. Despite technological advances, the basic steps of smoking remain essentially the same as they were centuries ago.