How Infrared Grills Work

Even with prices on infrared grills dropping, backyard grilling enthusiasts may consider the cost of the technology -- anywhere from $500 for tabletop models to $1,000 for free-standing versions as of 2011 -- a splurge [source: Associated Press]. (Perhaps adopters have trimmed from their grilling-related budgets, buying smaller steaks, more in-season vegetables and fewer novelty aprons.)

Infrared heat may be a hot new trend in grilling, but this type of heat has been occurring naturally since the dawn of time. In fact, everything with a temperature above absolute zero (which is equal to -459.67 degrees Fahrenheit or -273.15 degrees Celsius) emits at least a little infrared radiation. If you're wondering how this ancient, ubiquitous form of heat has been harnessed for home cooking use, it will help to understand how it's generated.

Infrared waves are part of the electromagnetic spectrum, sandwiched between visible light waves and microwaves. Within the infrared range, different types of infrared waves are characterized by frequency -- near, mid or far -- based on how many waves pass a given point each second [source: Study Physics]. At certain wavelengths within the infrared range, infrared waves create heat that human beings can sense.

Near infrared waves, like those activated by pushing a button on a television remote control, have the shortest frequencies and don't emit heat that humans can sense. Far infrared waves, however, have longer frequencies and are interpreted by humans' temperature-sensitive nerve endings as heat. For example, you can feel infrared heat when you're outdoors in the sunlight, when you walk barefoot on a warm sidewalk or when you stand near a wood-burning fireplace.

Therefore, infrared heat is present to some degree in any type of grill, from charcoal to wood fired to gas. As the temperature of a grill increases, it emits a greater amount of infrared heat. A charcoal grill can heat to about 700 degrees Fahrenheit (371 degrees Celsius), whereas a traditional gas grill typically reaches about 750 degrees Fahrenheit (398 degrees Celsius). An infrared grill, however, averages about 900 degrees Fahrenheit (482 degrees Celsius) and can reach up to 1,600 degrees Fahrenheit (871 degrees Celsius) -- the same temperature required for rocks to start melting near the Earth's core [source: Hunter, Associated Press, Oregon State].

This intense heat is then transferred to foods, a process we'll explore in greater detail on the next page.

Gas and charcoal grills cook primarily though convection. As the air in the grill is continually heated by the burning charcoal or the gas flame, the air rises and circulates around the food on the grill's grate, causing the food to cook. This constant flow of air can also dry food out.

An infrared grill, instead of relying on hot air to transfer heat to food, uses an electric or gas element to heat a solid surface, which then radiates, or emits, far infrared waves directly into the food that sits on the grill's grate. The heating element also heats the air in the grill, creating some convection, but less air is circulated and therefore the food retains more moisture during cooking. With their higher temperatures, infrared grills can also cook food faster than standard grills. (More about that on the next page.)

Early infrared grills manufactured for commercial use were equipped with bare ceramic heating surfaces, which created a large amount of convection and could be finicky and difficult to clean. Many of the newer infrared grill models feature designs that layer ceramic or metal heating surfaces with glass plates that direct air flow away from the food and provide high-temperature, evenly diffused infrared heat, which proponents say results in more even cooking than grills that rely entirely on convection [source: Associated Press]. However, independent tests have shown that high-end gas grills provide equally even heating and cooking [source: Consumer Reports].

If you're thinking that an infrared grill would be great for searing a steak but would surely incinerate your favorite vegetable medley, think again. The heat is adjustable, and although it won't reach the (relatively) mellow temperatures of smoldering charcoal, an infrared grill can still be used for everything from roasting chicken to steaming vegetables -- though extra care should be taken while you adjust to an infrared grill's quick cooking speeds.

Even if you're fond of DIY projects, keep in mind that placing a ceramic, metal or glass plate across your standard grill won't turn it into an infrared grill. "The optimum burner," says Ted Wegert, a ceramic engineer with Schott North America Inc. who works directly with a variety of grill manufacturers to introduce and improve the art of infrared cooking, "is one specifically designed to emit heat in the infrared wavelength range best suited for passing through the plate and for optimum cooking."

On the next page, learn more about the specifics of cooking with an infrared grill.

Traditional gas grills require about 10 minutes to preheat, and charcoal grills need about 20 minutes for the briquettes to reach an ideal cooking temperature. Infrared grills, however, can reach top temperatures within three to five minutes [source: Hunter].

The high temperatures of infrared grills cut the cooking time of proteins by about half when compared to their cooking time on traditional gas or charcoal grill grates. The result is a medium-rare steak in about five minutes or a fully cooked chicken breast in about 10 minutes.

To prevent food-borne illnesses, grilled proteins must be cooked to the correct internal temperature. According to the U.S. Department of Agriculture, recommended temperatures include:

"The best way to measure the internal temperatures of foods on an infrared grill is using a thermometer," said Richard Wachtel, the founder of Grilling with Rich, an online magazine that specializes in educating competitive grillers. As of 2011, you could purchase a probe-style digital thermometer for less than $20 in most places where cooking equipment is sold.

Even with a thermometer to measure food temperatures and a home library stocked with cookbooks, learning how to create culinary masterpieces on an infrared grill takes practice. Because infrared surfaces heat to between two and three times the temperature of traditional grills, foods can burn much more quickly than you may expect. While it may take five minutes to sear a 2-inch-thick tenderloin, for example, grilled asparagus requires only a minute or two. Watch food carefully the first time you try cooking it on an infrared grill.

For some people, however, the real challenge begins when the grill's work is done. After spending hundreds or possibly thousands of dollars on an infrared grill, caring for it reaches a whole new level of importance. On the next page, we'll share some tips for maintaining your infrared grill.

At least twice a year, an infrared grill should be inspected for wear, paying close attention to any damage to the heating element, the infrared plate and the grate. Worn parts should be replaced before using and can usually be ordered directly from the manufacturer. If you're not the DIY type, at least not when it comes to expensive, restaurant-grade grills, you may want to contact the grill's manufacturer to locate an authorized repair facility.

If your infrared grill is in working order, first clean the grill's gas or electric heating element by removing debris with a wire brush or steel wool and, in the case of gas elements, clearing out any obstructions to the burner's openings.

Next, if your infrared grill is equipped with a grate, apply some elbow grease. Remove the grate and, if it's made of metal, whisk a stiff wire brush over both sides to remove cooking debris. If the grate is cast iron or coated with porcelain, use a brush with soft nylon bristles to avoid etching the grate's surface [source: Consumer Reports]. To finish the job, turn up the heat.

"One of the best ways to clean your grill is to heat up the grill to as high a temperature as possible," said Wachtel -- doing so will burn off any remaining debris. Then, after the grill cools, you can use a grill brush to remove leftover particles.

Finally, concentrate on the infrared heating surface. Whether it's made of ceramic, metal or glass, it's best to gently brush off any ash or food particles, and then to use a gentle, nonabrasive chemical cleaner to break up stubborn deposits [source: Vaglica].

It's recommended that an infrared grill be thoroughly cleaned biannually, but some people like to do so more often, up to every time they use it. "I usually like to clean all my grills, both gas and infrared, once a season, but it is totally preference-based," said Wachtel.

With an infrared grill so clean that you could, well, eat off of it, the only thing left do is prepare a marinade, wash a few vegetables and don an apron. When you fire up an infrared grill, the rest will take care of itself in mere minutes.