To barbecue gurus like Steven Raichlen, it's a non-starter. ("My advice: don't," he writes in his book "Project Smoke.") Others are more open to the idea.
"Most people think of smoke and believe that it's something handled by pitmasters with these giant rigs, and that's the stereotypical image," says Jamie Purviance, author of several grilling books, including "Weber's Smoke." "But you can use a gas grill to get that smoky flavor."
It's possible, but not easy. Frankly, the gas grill is not ideal for smoking. Unlike smokers, which are designed to provide a deeply smoked flavor through wood smoldering over long periods, or even charcoal grills, which allow for the use of big hardwood chunks to swaddle food in vapors, gas doesn't provide that charred flavor. Plus, as Raichlen points out, wide venting in many gas grills allows smoke to escape. The grills are designed to handle a diaphanous, ephemeral smoke, not a penetrating one.
Grill manufacturers, though, have taken notice of an increase in interest in true barbecue. Mike Kempster, former global chief marketing officer for Weber-Stephen Products, says that over the past decade, the company has seen an uptick in the number of people calling and emailing with questions about smoking. Weber responded by manufacturing, among other things, perforated metal smoker boxes designed to be put inside a gas grill.
The average gas grill, which can cost from $200 to $1,000, has come a long way since the days when ceramic briquettes or lava rocks provided the heat. Now, it is more common to find angled steel heat shields over the burners. "Heat tents protect the burner," says Clark Turner, director of product management for Char-Broil. "They reduce flareups and even out the heat."
Although they're still not as good for smoking as charcoal, today's gas grills can achieve some pretty good smoking results — if you understand their limitations. Here's how to start:
Get a receptacle for wood chips or chunks. They will smolder and create the smoke that wafts across the food. (If you have a high-end grill, it may have a built-in smoker box, set directly above a burner.)
Most free-standing smoker boxes are rectangular and cost about $20. Make sure to get a heavy-gauge stainless-steel one that can stand up to the grill's heat. These are set on the cooking grate or on the angled metal plates beneath the grate. There are also V-shaped boxes, for placement between the plates.
You can also jury-rig a smoker pouch by placing wood chips in the center of a 12-by-16-inch sheet of aluminum foil, closing it up, and poking a few holes in it to allow smoke to escape. Like the rectangular box, it can be set on the cooking grate or on the angled metal plates.
Put the smoker box onto the cooking grate before starting your grill. The distance from the fire will help keep the wood chips from flaming and, because they'll take a little longer to catch, the grill will be fully preheated by the time smoke appears.
Soak chips or chunks of oak, hickory, pecan, apple or some other fruitwood or hardwood in water for an hour, then drain and add them to the box or pouch. Place the box back on the grill and turn all the burners to high to preheat.
Cook with indirect heat: fire on one side, no fire on the other. When you see smoke, turn off the side of the grill that's not under the smoker box. Set the knobs on the hot side (where you've placed the box or pouch) to the desired temperature. Put the food on the cool side, close the lid and wait until the food is done.
This is where the limitations come in.
It's possible to smoke large meats such as a pork shoulder or a brisket on a gas grill, but it's unlikely that they'll come out as deeply flavorful as you want. Why? One, wood chips in smoker boxes don't last very long, and you'd have to replace the pouch every half-hour for eight or 12 or even 18 hours. Two, wood chips provide more of a wisp than a plume of smoke, so your food won't have that brawny, outdoorsy flavor. You can use chunks for longer-lasting smoke, but even they are inadequate to the task because there's the aforementioned problem with smoke escaping out the vents.
Better, then, to use the gas grill for daintier foods that will take smoke more easily and quickly. Focus on these:
Appetizers, such as spiced mixed nuts . Sprinkled with brown sugar and cayenne, the nuts take on a classic sweet-hot flavor and are imbued with an earthiness when hickory-smoked. They take only 30 minutes to cook, are addictive and keep well in a sealed jar.
Fish, particularly fillets and steaks. Like the mixed nuts, they quickly absorb the smoke, and because the waft of smoke is gentle, there is little fear of oversmoking, a concern with fish. Meaty fish, such as bluefish, mackerel and swordfish, work particularly well. One of my favorites is the buttery and juicy Chilean sea bass, which is dense yet moist, inviting the smoke to imbue the flesh with a light campfire fragrance.
Sausages. They can gently roast, which keeps the meat moist but cooks it through. (Sausage is often grilled or fried, which tends to burn the outside while leaving the interior underdone.) They take only about 40 minutes, making for an easy weekday meal.
In "Project Smoke," Raichlen offers a bratwurst recipe that comes out juicy inside and snappy outside. He calls for you to hot-smoke them over hardwood. But it comes out so well on a gas grill that it might make even him a believer.
Shahin is an associate professor of journalism at Syracuse University. He will join Wednesday's Free Range chat at noon:
. Follow him on Twitter: @jimshahin.
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