Копчение продуктов: история, методы и виды древесины

Exposing food to smoke to flavor or preserve it

Smoking is the process of flavoring, browning, cooking, or preserving food by exposing it to smoke from burning or smoldering material, most often wood. Meat, fish, and lapsang souchong tea are often smoked. In Europe, alder is the traditional smoking wood, but oak is more often used now, and beech to a lesser extent. In North America, hickory, mesquite, oak, pecan, alder, maple, and fruit tree woods, such as apple, cherry, and plum, are commonly used for smoking. Other biomass besides wood can also be employed, sometimes with the addition of flavoring ingredients. Chinese tea smoking uses a mixture of uncooked rice, sugar, and tea, heated at the base of a wok. Some North American ham and bacon makers smoke their products over burning corncobs. Peat is burned to dry and smoke the barley malt used to make Scotch whisky and some beers. In New Zealand, sawdust from the native manuka (tea tree) is commonly used for hot smoking fish. In Iceland, dried sheep dung is used to cold smoke fish, lamb, mutton, and whale. Historically, farms in the Western world included a small building termed the "smokehouse", where meats could be smoked and stored. This was generally well separated from other buildings both because of fire danger and smoke emanations. The smoking of food may possibly introduce polycyclic aromatic hydrocarbons, which may lead to an increased risk of some types of cancer; however, this association is still being debated. Smoking can be done in four ways: cold smoking, warm smoking, hot smoking, and through the employment of a smoke flavoring, such as liquid smoke.

The smoking of food likely dates back to the paleolithic era. As simple dwellings lacked chimneys, these structures would probably have become very smoky. It is supposed that early humans would hang meat up to dry and out of the way of pests, thus accidentally becoming aware that meat that was stored in smoky areas acquired a different flavor, and was better preserved than meat that simply dried out. This process was later combined with pre curing the food in salt or salty brine, resulting in a remarkably effective preservation process that was adapted and developed by numerous cultures around the world. Until the modern era, smoking was of a more "heavy duty" nature as the main goal was to preserve the food. Large quantities of salt were used in the curing process and smoking times were quite long, sometimes involving days of exposure. Smokehouse temperatures for cold smoking are typically between In this temperature range, foods take on a smoked flavor, but remain relatively moist. Since cold smoking does not cook foods, meats should be fully cured before cold smoking. Cold smoking meats should only be attempted by personnel certified in HACCP [ ] to ensure that it is safely prepared. Unreliable source: date=October 2019

Warm smoking exposes foods to temperatures of In North America, this smoking method is commonly referred to as "barbecuing", "pit baking", or "pit roasting".

Hardwoods are made up mostly of three materials: cellulose, hemicellulose, and lignin. Cellulose and hemicellulose are the basic structural material of the wood cells; lignin acts as a kind of cell bonding glue. Some softwoods, especially pines and firs, hold significant quantities of resin, which produces a harsh tasting soot when burned; these woods are not often used for smoking. Cellulose and hemicellulose are aggregate sugar molecules; when burnt, they effectively caramelize, producing carbonyls, which provide most of the color components and sweet, flowery, and fruity aromas. Lignin, a highly complex arrangement of interlocked phenolic molecules, also produces a number of distinctive aromatic elements when burnt, including smoky, spicy, and pungent compounds such as guaiacol, phenol, and syringol, and sweeter scents such as the vanilla scented vanillin and clove like isoeugenol. Guaiacol is the phenolic compound most responsible for the "smoky" taste, while syringol is the primary contributor to smoky aroma. Wood also contains small quantities of proteins, which contribute roasted flavors. Many of the odor compounds in wood smoke, especially the phenolic compounds, are unstable, dissipating after a few weeks or months. A number of wood smoke compounds act as preservatives. Phenol and other phenolic compounds in wood smoke are both antioxidants, which slow rancidification of animal fats, and antimicrobials, which slow bacterial growth. Other antimicrobials in wood smoke include formaldehyde, acetic acid, and other organic acids, which give wood smoke a low pH—about 2.5. Some of these compounds are toxic to people as well, and may have health effects in the quantities found in cooking applications. Since different species of trees have different ratios of components, various types of wood do impart a different flavor to food. Another important factor is the temperature at which the wood burns. High temperature fires see the flavor molecules broken down further into unpleasant or flavorless compounds. The optimal conditions for smoke flavor are low, smoldering temperatures between This is the temperature of the burning wood itself, not of the smoking environment, which uses much lower temperatures. Woods that are high in lignin content tend to burn hot; to keep them smoldering requires restricted oxygen supplies or a high moisture content. When smoking using wood chips or chunks, the combustion temperature is often raised by soaking the pieces in water before placing them on a fire.

The main characteristics of the offset smoker are that the cooking chamber is usually cylindrical in shape, with a shorter, smaller diameter cylinder attached to the bottom of one end for a firebox. To cook the meat, a small fire is lit in the firebox, where airflow is tightly controlled. The heat and smoke from the fire are drawn through a connecting pipe or opening into the cooking chamber. The heat and smoke cook and flavor the meat before escaping through an exhaust vent at the opposite end of the cooking chamber. Most manufacturers' models are based on this simple but effective design, and this is what most people picture when they think of a "BBQ smoker". Even large capacity commercial units use this same basic design of a separate, smaller fire box and a larger cooking chamber.

The upright drum smoker (also referred to as an ugly drum smoker or UDS) is exactly what its name suggests: an upright steel drum that has been modified for the purpose of pseudo indirect hot smoking. There are many ways to accomplish this, but the basics include the use of a complete steel drum, a basket to hold charcoal near the bottom, and a cooking rack (or racks) near the top, all covered by a vented lid of some sort. These smokers have been built using many different sizes of steel drums, such as , , and , but the most popular size is the common 55 gallon drum. This design is similar to smoking with indirect heat due to the distance between the coals and the cooking racks, which is typically The temperature is controlled by limiting the air intake at the bottom of the drum, and allowing a similar amount of exhaust out of vents in the lid. UDSs use their fuel very efficiently, and are flexible in their ability to produce proper smoking conditions with or without the use of a water pan or drip pan.

A vertical water smoker (also referred to as a bullet smoker because of its shape) is a variation of the upright drum smoker. It uses charcoal or wood to generate smoke and heat, and contains a water bowl between the fire and the cooking grates.

Commercial smokehouses, mostly made from stainless steel, have independent systems for smoke generation and cooking. Smoke generators use friction, an electric coil or a small flame to ignite sawdust on demand. Heat from steam coils or gas flames is balanced with live steam or water sprays to control the temperature and humidity. Elaborate air handling systems reduce hot or cold spots, to reduce variation in the finished product. Racks on wheels or rails are used to hold the product and facilitate movement.

A pellet smoker is a temperature controlled smoker that burns wood pellets made of dried out sawdust, about an inch long and 1/4 inch wide. The wood pellets are stored in a gravity fed hopper that feeds into a motor controlled auger by the temperature regulator. This auger pushes the pellets into the fire pot. An ignition rod within the auger ignites the pellets where a combustion fan keeps them smouldering. The motor and the combustion fan regulate the temperature of the smoker by feeding it more pellets and increasing airflow in the auger. Above the auger is a heat shield to disperse the direct heat before it reaches the heat box to allow the wood smoke to keep the heat box at an even temperature throughout. The heat sensor inside the heat box relays the current temperature inside the box back to the temperature regulator that controls the fan speed and pellet hopper motor, which either increase or decrease the amount of pellets in the auger or the amount of air available to the fire to maintain the desired temperature for the cook. The popularity of this type of smoker is on the rise after many BBQ pit masters began using them in barbecue competitions.

Smoke is both an antimicrobial and antioxidant, but it is insufficient for preserving food because it does not penetrate far into meat or fish; therefore, if the food is to be preserved, smoking is typically combined with salt curing or drying. Smoking is especially useful for oily fish, as its antioxidant properties inhibit surface fat rancidification and delay oxygen from reaching the interior fat and degrading it. Some heavily salted, long smoked fish can keep without refrigeration for weeks or months. Artificial smoke flavoring (such as liquid smoke) can be purchased to mimic smoking's flavor, but such products have no preservative qualities.

Competitive BBQ smoking is becoming increasingly popular, especially in the southern United States, where BBQ enthusiasts come together over a weekend to cook various cuts of meat such as a whole hog or a beef brisket. Organisations such as Kansas City Barbeque Society run competitions all over America.

Regularly consuming smoked meats and fish may increase the risk of several types of cancer.