There are multiple varieties of grills, with most falling into one of two categories: gas-fueled and charcoal. There is a great debate over the merits of charcoal or gas for use as the cooking method between grillers. Electric indoor grills have also recently become popular.
Grilling is a pervasive tradition in the United States. There are many cook-offs for steak grilling and barbecue (midwestern and southern style) around the United States with serious cash prizes involved in most. Almost all competition grillers use charcoal, most often in large, custom designed brick or steel grills. They can range from a few 55 gallon oil drums sawed lengthwise on their sides to make a lid and grill base, to large, vehicle sized grills made of brick, weighing nearly a ton.
Another personality in the charcoal grilling camp is George Stephen. The stereotypical American charcoal grill is a hollow, metal hemisphere with three legs and a small metal disc to catch ash, with a lower grate to hold the charcoal and an upper grate to hold the food to be cooked. George Stephen created the hemispherical grill design, jokingly called "Sputnik" by Stephen's neighbors. Stephen, a welder, worked for Weber Brothers Metal Works, a metal fabrication shop primarily concerned with welding steel spheres together to make buoys. Stephen was tired of wind blowing ash onto his food when he grilled. One day he had an epiphany: he took the lower half of a buoy, welded three steel legs onto it, and fabricated a shallower hemisphere for use as a lid. He took the results home and within weeks was selling the grills first to his neighbors, then to customers, and finally started the Weber-Stephen Products Co. Weber grills come in many sizes, again, in small 14 inch diameter grills up to a full size 24 inch diameter grill.
Gas-fueled grills typically use propane (LP) or natural gas (NG) as their fuel source, with gas-flame either cooking food directly or heating grilling elements which in turn radiate the heat necessary to cook food. Gas grills are available in sizes ranging from small, single steak grills up to large, industrial sized restaurant grills which are able to cook enough meat to feed a hundred or more people. Gas grills are designed for either LP or NG, although it's possible to convert a grill from one gas source to another.
The majority of gas grills follow the cart grill design concept: the grill unit itself is attached to a wheeled frame that holds the fuel tank. The wheeled frame may also support side tables and other features.
A recent trend in gas grills is for the manufacturers to add an infrared radiant burner to the back of the grill enclosure. This radiant burner provides an even heat across the burner and is intended for use with a horizontal rotisserie. A meat item (whole chicken, beef roast, pork loin roast) is placed on a metal skewer that is rotated by an electric motor. Smaller cuts of meat can be grilled in this manner using a round metal basket that slips over the metal skewer.
Another type of gas grill gaining popularity is called a flattop grill. According to Hearth and Home magazine, flattop grills "on which food cooks on a griddlelike surface and is not exposed to an open flame at all" is an emerging trend in the outdoor grilling market.
A small metal "smoker box" containing wood chips may be used on a gas grill to give a smoky flavor to the grilled foods.
Infrared grills work by igniting propane or natural gas to superheat a ceramic tile, causing it to emit infrared radiation that cooks food. The benefits are that heat is uniformly distributed across the cooking surface and that temperatures reach over 500 °C (900 °F), allowing users to sear items quickly.
Infrared cooking differs from other forms of grilling, which use hot air to cook the food. Instead of heating the air, infrared radiation heats the food directly. The benefits of this are a reduction in pre-heat time and less drying of the food. Grilling enthusiasts claim food cooked on an infrared grill tastes similar to food from char-grills. This is because charcoal, when burned, emits infrared radiation, the same as an infrared grill, but the difference is that char-grills cook with only 25% (see New Advances below) infrared heat with the remaining 75% from hot air. The result is that food cooked on infrared grills seems juicier. Also, infrared grills have the advantages of instant ignition, better heat control, and a uniform heat source.
This technology was patented by a company called TEC Infrared (Thermo Engineering Corporation of Columbia, SC - a company owned by scientist and founder Bill Best), but the patents have expired as of the year 2000 and other companies have started offering infrared grills at lower prices. Since then, many restaurants have begun upgrading their kitchens to infrared technology due to the significant reduction in cooking time, lower operational cost, and lower environmental impact. Infrared grills grill more food in less time, and use less fuel (natural gas or propane) over the entire grilling cycle. This results in reduced greenhouse gases and less heat released into the atmosphere.
Sear-grilling has become a common term for an infrared grill's unique ability to instantly sear meat, unlike any other cooking technology.
Advantages: Fast preheat time 2 to 3 minutes, reaches temperatures of 900 degrees Fahrenheit, uniform heat distribution, cooks meats from outside-in, sears outside of meat so juices stay locked in, instant ignition, uniform heat pattern, easier clean-up as drippings instantly vaporize from the extreme heat, less chance of flare-up.
Disadvantages: Typically more expensive than similar-sized conventional gas or charcoal grills, although recent changes have made prices drop considerably. Inexperienced users can easily overcook meat/food due to the high temperatures.
New Advances: As of Early 2008, companies continue patenting new 100% infrared technologies (the old technology only achieves a maximum level of 50% infrared.)
There is contention among grilling enthusiasts on what type of charcoal is best for grilling. Users of charcoal briquets emphasize the uniformity in size, burn rate, heat creation, and quality exemplified by briquets. Users of all-natural lump charcoal emphasize the reasons they prefer it: subtle smoky aromas, high heat production, and lack of binders and fillers often present in briquets.
There are many different charcoal grill configurations. Some grills are square, round, or rectangular, some have lids while others do not, and some may or may not have a venting system for heat control. The majority of charcoal grills, however, fall into the following categories:
The simplest and most inexpensive of charcoal grills, the brazier grill is made of wire and sheet metal and composed of a cooking grid placed over a charcoal pan. Usually the grill is supported by legs attached to the charcoal pan. The brazier grill does not have a lid or venting system. Heat is adjusted by moving the cooking grid up or down over the charcoal pan. Even after George Stephen invented the kettle grill in the early 1950s, the brazier grill remained a dominant charcoal grill type for a number of years. Brazier grills are available at most discount department stores during the summer.
Pellet grills are fueled by compressed hardwood pellets (sawdust compressed with vegetable oil at approx. 10k psi) that are loaded into a hopper and fed into a fire box at the bottom of the grill via an electric powered auger that is controlled by a thermostat. The pellets are lit by an electric igniter rod that starts the pellets burning and they turn into coals in the firebox once they burn down. Most pellet grills are a barrel shape with a square hopper box at the end or side.
The advantage of a pellet grill is that it can be set on a "smoke" mode where it burns at 100 to 150 degrees for slow smoking. It can be set at 180 to 300 to slow cook or BBQ meats (like brisket, ribs and hams) or cranked up to a max of 450 to 500 degrees for what would be considered low temp. grilling. It is one of the few "grills" that is actually a great smoker, a fantastic BBQ and a decent grill. Critics argue that a good "grill" should be able to exceed 500 degrees to sear the meat.
Most pellet grills burn 1/2 to 1 pound of pellets per hour at 180 to 250 degrees, depending on the "hardness" of the wood, ambient temp. and (of course) how often the lid is opened. Most hoppers hold 10 to 20 pounds of wood pellets. Pellets in a wide variety of woods (hickory, oak, maple, apple, alder, mesquite, grapevine, etc..) can be used or mixed for desired smoke flavoring.
The Square Charcoal grill is a hybrid of the brazier and the kettle grill. It has a shallow pan like the brazier and normally a simple method of adjusting the heat, if any. However, it has a lid like a kettle grill and basic adjustable vents. The square charcoal grille is, as expected, priced between the brazier and kettle grill, with the most basic models priced around the same as the most expensive braziers and the most expensive models competing with basic kettle grills. These grills are available at discount stores and have largely displaced most larger braziers. Square charcoal grills almost exclusively have four legs with two wheels on the back so the grill can be tilted back using the handles for the lid to roll the grill. More expensive examples have baskets and shelves mounted on the grill.
The kettle grill is considered the classic American grill design. The original and often-copied Weber kettle grill was invented in 1951 by George Stephen. It has remained one of the best and most reliable charcoal grill designs to date. Smaller and more portable versions exist, such as the Weber Smokey Joe. The kettle grill is composed of a lid, cooking grid, charcoal grid, lower chamber, venting system, and legs. Some models include an ash catcher pan and wheels. The lower chamber that holds the charcoal is shaped like a kettle, giving the grill its name. The key to the kettle grills' cooking abilities is its shape. The kettle design distributes heat more evenly. When the lid is placed on the grill, it prevents flare-ups from dripping grease, and allows heat to circulate around the food as it cooks. It also holds in flavor-enhancing smoke produced by the dripping grease or from smoking wood added to the charcoal fire.
The kettle design allows the griller to configure the grill for indirect cooking (or barbequing) as well. For indirect cooking, charcoal is piled on one or both sides of the lower chamber and a water pan is placed in the empty space to one side or between the charcoal. Food is then placed over the water pan for cooking. The venting system consists of one or more vents in the bottom of the lower chamber and one or more vents in the top of the lid. Normally, the lower vent(s) are to be left open until cooking is complete, and the vent(s) in the lid are adjusted to control airflow. Restricted airflow means lower cooking temperature and slower burning of charcoal.
The portable charcoal grill normally falls into either the brazier or kettle grill category. Some are rectangular in shape. A portable charcoal grill is usually quite compact and has features that make it easier to transport, making it a popular grill for tailgating. Often the legs fold up and lock into place so the grill will fit into a car trunk more easily. Most portable charcoal grills have venting, legs, and lids, though some models do not have lids (making them, technically, braziers.)
In addition to providing the cooking heat, the gas burners in a hybrid grill can be used to quickly start a charcoal/wood fire or to extend the length of a charcoal/wood cooking session.
A gas grill burner is the central source of heat for cooking food. Gas grill burners are typically constructed of:
Burners are hollow with gas inlet holes and outlet 'ports'. For each inlet is a separate control on the control panel of the grill. The most common type of gas grill burners are called 'H' burners and resemble the capital letter 'H' turned on its side. Another popular shape is oval. There are also 'Figure 8', 'Bowtie' and 'Bar' burners. Other grills have a separate burner for each control. These burners can be referred to as 'Pipe', 'Tube', or 'Rail' burners. They are mostly straight since they are only required to heat one portion of the grill.
Gas is mixed with air in venturi tubes or simply 'venturis'. Venturis can be permanently attached to the burner or removable. At the other end of the venturi is the gas valve, which is connected to the control knob on the front of the grill.
A metal screen covers the fresh air intake of each venturi.
Many refer to a cooking grid's front to back dimension as 'width' and the side to side dimension as 'length.' Alternate terminology defines the 'depth' of a cooking grid as measured from to front back and the 'width' as measured from side to side.
Like lava rock or ceramic briquettes, heat shields also vaporize the meat drippings and 'infuse' the meat with more flavor.
If a valve seems to be moving properly, but no gas is getting to the burner, the most common cause for this is debris in the venturi. This impediment can be cleared by using a long flexible object.
While live-fire cooking is difficult indoors without heavy-duty ventilation, it is possible to simulate some of the effects of a live-fire grill with indoor equipment. The simplest design is known as a grill pan, which is a type of heavy frying pan with raised grill lines to hold the food off the floor of the pan and allow drippings to run off. Though they have only become popular since the 1990s, such pans are widely recommended for apartment dwellers and people who live in areas where outdoor cooking is impractical for weather reasons.
The George Foreman indoor grill, which was introduced in 1995, uses a hinged design with top and bottom Teflon-coated heating surfaces covered in a pattern of ridges. As the meat is grilled between the two electrically-heated surfaces, excess fat drains out to a small trough-like dish. By grilling on both sides simultaneously, cooking time is reduced (hamburgers can be done in as little as five minutes) and the food is cooked more evenly. The Foreman grill is one of the better-known representatives of a broad category sometimes known as contact grills; a panini press is a similar device with somewhat more tightly arranged ridges.