Barbecuing encompasses four distinct types of cooking techniques. The original technique is cooking using smoke at lower temperatures (usually around 240°F) and significantly longer cooking times (several hours), known as smoking. Another technique is baking, utilizing a masonry oven or any other type of baking oven, which uses convection to cook meats and starches with moderate temperatures for an average cooking time (about an hour plus a few extra minutes). Yet another technique is braising, which combines direct dry heat charbroiling on a ribbed surface with a broth-filled pot for moist heat, cooking at various speeds throughout the duration (starting fast, slowing down, then speeding up again, lasting for a few hours). Finally, grilling is done over direct dry heat, usually over a hot fire (i.e., over 500°F) for a short time (minutes). Grilling may be done over wood, charcoal, gas (natural gas or propane), or electricity.
Smoking can be done with wood or charcoal, although many common commercial smokers use a gas, such as propane, to heat up a box of wet wood chips enough to cause smoke. The heat from the propane fire helps cook the meat while the smoke adds its unique and delicious flavor. The distinction between smoking and grilling is the heat level and the intensity of the radiant heat; indeed, smoking is often referred to as “low and slow”. Additionally, during grilling, the meat is exposed to the open air for the majority of the time. During smoking, the BBQ lid or smoker door is closed, making a thick dense cloud of smoke to envelop the meat. The smoke must be able to move freely around the meat and out of the top of the apparatus quickly; otherwise, foul-tasting creosote will build up on the meat, giving it a bitter flavor. Smoked meats such as pork exhibit what is known as a smoke ring: a thin pink layer just under the surface which is the result of the smoke interacting with the water in the meat.
The masonry oven is similar to a smoke pit in that it allows for an open flame, but cooks much faster, and uses convection to cook. Barbecue-baking can also be done in traditional stove-ovens. It can be used to cook not only meats, but breads and other starches, and even various casseroles and desserts. It uses both direct and indirect heat to surround the food with hot air to cook, and can be basted much the same as grilled foods. In some cases, the grill can also function like a bakery oven by putting a drip pan below the cooking surface rack of a barbecue grill, as well as a baking sheet pan on top, combining two techniques simultaneously, or one right after the other, cooking twice, with a duration slightly longer than grilling.
Meat can also be baked in a pit in the ground, with hot coals and stones surrounding meat wrapped in wet burlap, wet leaves or aluminum foil.
It is possible to braise meats and vegetables in a pot on top of a grill. A gas or electric charbroil grill would be the best choices for what is known as barbecue-braising, or combining dry heat charbroil-grilling directly on a ribbed surface and braising in a broth-filled pot for moist heat. To braise, put a pot on top of the grill, cover it, and let it simmer for a few hours. There are two advantages to barbecue-braising: the first is that this method now allows for browning the meat directly on the grill before the braising, and the second is that it also allows for glazing the meat with sauce and finishing it directly over the fire after the braising, effectively cooking the meat three times, which results in a soft textured product that falls right off the bone. This method of barbecue has a varying duration (depending on whether a slow cooker or pressure cooker is used), and is generally slower than regular grilling or baking, but faster than pit-smoking.
Grilling (gridironing, charbroiling)
The choice and combination of woods burned result in different flavors imparted to the meat. Woods commonly selected for their flavor include mesquite, hickory, maple, guava, kiawe, cherry, pecan, apple and oak. Woods to avoid include conifers. These contain resins and tars, which impart undesirable resinous and chemical flavors. If these woods are used, they should be burned in a catalytic grill, such as a rocket stove, so that the resins and tars are completely burned before coming into contact with the food.
Different types of wood burn at different rates. The heat also varies by the amount of wood and controlling the rate of burn through careful venting. Wood and charcoal are sometimes combined to optimize smoke flavor and consistent burning.
Cooking with charcoal, like cooking with gas, is a more manageable approximation of cooking over a wood fire. Charcoal does not impart the rich flavor of cooking over hardwoods but is cheap and easy to purchase in sizes appropriate for close proximity cooking in typical commercially available home grills and griddles.
Charcoal grid ironing generally begins with purchasing a commercial bag of processed charcoal briquettes. An alternative to charcoal briquettes is lump charcoal. Lump charcoal is wood that has been turned into charcoal, but unlike briquettes, it has not been ground and shaped. Lump charcoal is a pure form of charcoal and is preferred by many purists who dislike artificial binders used to hold briquettes in their shape, and it also burns hotter and responds to changes in airflow much more quickly. Charcoal cannot be burned indoors because poisonous carbon monoxide (CO) is a combustion product. Carbon monoxide fumes may contribute to the pink color taken on by barbecued meats after slow cooking in a smoker. Many barbecue aficionados prefer charcoal over gas (natural gas or propane) for the authentic flavor the coals provide.
A charcoal chimney starter is an inexpensive and efficient method for quickly obtaining a good charcoal fire. A few pages of newspaper are wadded up underneath the chimney to start the fire. Other methods are to use an electric iron to heat the charcoal or to soak it with aliphatic petroleum solvent and light it in a pyramid formation. Charcoal briquettes pre-impregnated with solvent are also available. Although the use of solvents is quick and portable, it can be hazardous, and petroleum solvents can impart undesirable chemical flavors to the meat. Using denatured alcohol (“methyl hydrate”, “methylated spirit”) instead of commercial petroleum-based lighter fluids avoids this problem.
Once all coals are ashed over (generally 15–25 minutes, depending on starting technique), they can be spread around the perimeter of the grill with the meat placed in the center for indirect cooking, or piled together for direct cooking. Water-soaked wood chips (such as mesquite, cherry, hickory or fruit trees) can be added to the coals for flavor. As with wood barbecuing, the temperature of the grill is controlled by the amount and distribution of coal within the grill and through careful venting.
For long cooking times (up to 18 hours), many cooks find success with the minion method, usually performed in a smoker. The method involves putting a small number of hot coals on top of a full chamber of unlit briquettes. The burning coals will gradually light the unlit coals. By leaving the top air vent all the way open and adjusting the lower vents, a constant temperature of 225°F can easily be achieved for up to 18 hours.
The Japanese-style kamado cooker utilizes lump charcoal for fuel. The kamado is made from ceramics and can be adjusted to cook for more than 30 hours on a single load of lump, the heat being retained in the ceramic walls, radiating into the food. There is no need to use water pans or replenish fuel during the cook, as is the case with steel water smokers. Furthermore, lump charcoal contains no additives or fillers as contained in charcoal briquettes. The very small amount of air needed to keep a ceramic cooker going at low temperature helps maintain a moist environment, whereas in a steel smoker, steam must be added from a water pan over the briquettes to keep the food from drying out. The kamado dates back several thousand years with roots in China and Japan.
Natural gas, propane, and electricity
Grilling with natural gas, propane, or electricity is a step further removed from cooking over a wood fire. Despite this, and the higher cost of a gas grill over a charcoal grill, many people continue to prefer cooking over a gas flame or electric element. There are also some hybrid charbroilers and griddles that combine these two energy sources together for cooking.
Gas grills are easy to light. The heat is easy to control via knob-controlled gas valves on the burners, so the outcome is very predictable. Gas grills give very consistent results, although some charcoal and wood purists argue that it lacks the flavors available only from cooking with charcoal. Advocates of gas grills claim that gas cooking lets you “taste the meat, not the heat” because it is claimed that charcoal grills may deposit traces of coal tar on the food. Many grills are equipped with thermometers, further simplifying the barbecuing experience. However, propane and natural gas produce a “wet” heat (combustion byproducts include water vapor) that can change the texture of foods cooked over such fuels.
Added wood smoke flavor can be imparted on gas and electric grills using water-soaked wood chips placed in an inexpensive smoker box (a perforated metal box), or simply a perforated foil pouch, under the grilling grate and over the heat. It takes some experience in order to keep the chips smoking consistently without catching fire; some high-end gas grills include a built-in smoker box with a dedicated burner to simplify the task. Using such smokers on quick-grilled foods (steaks, chops, burgers) nearly duplicates the effects of wood and charcoal grills, and they can actually make grilling some longer-cooked foods, such as ribs, easier, since the “wet” heat makes it easier to prevent the meat from drying out.
Gas and electric gridirons, charbroilers, and griddles are significantly more expensive due to their added complexity. They are also considered much cleaner, as they do not result in ashes, which must be disposed of, and also in terms of air pollution. Proper maintenance may further help reduce pollution. The useful life of a gas or electric grill or griddle may be extended by obtaining replacement gas grill parts when the original parts wear out. Most barbecues that are used for commercial purposes now use gas or electricity for the reasons above.
There have been a number of designs for barbecues that use solar power as a means of cooking food. The device usually involves the use of a curved mirror acting as a parabolic reflector, which focuses the rays of the sun on to a point where the food is to be heated