“Gas or Charcoal”? The most frequently asked question since “Chicken or Egg?” The flame war between charcoal grill purists and gas grill hotheads burns brighter than the debate between Mac and PC users. You should read some of the slop slung on the barbecue message boards. On second thought, don’t. Let me try to sort it out for you with a few inflammatory thoughts.
Grills are used mostly for three types of cooking:
1) High heat direct radiation cooking when the food is placed directly above the heat source for things like steaks. Usually there is no lid over the meat.
2) Indirect heat convection roasting for things like whole chickens and roasts when the heat source is off to the side and the food cooks by warm air circulating around it with the lid closed.
3) Indirect heat smoke roasting with the lid closed when the warm convection airflow is heavy with flavorful hardwood smoke.
There are other contenders that we will not include in this grudge match: Whole logs work similarly to charcoal, but logs are not readily available in many places, and working with them can be tricky. Wood pellets made from compressed sawdust are rapidly gaining in popularity, and although they are thermostatically controlled and superb smokers, they are not very good at direct radiant high heat grilling. And then there’s electricity, which does not get as hot as either charcoal or gas, and because there is no combustion, does not produce smoke. There are electric smokers which use wood chips to smolder, but the flavor is very different from gas and charcoal, and to my taste, inferior. To learn more about these methods, click the links, but for this day, we’ll let gas and charcoal duke it out. Let’s see how each fuel performs at these tasks and all the other factors.
Is there a taste difference?
The main differences in taste are the way the two systems brown surfaces, and the delivery of smoke flavor. There are pros and cons to both methods.
Searing is the process of browning the surfaces of meats, especially steaks. When done properly there are chemical reactions, the Maillard reaction and caramelization chief among them, that create savory compounds on the surface, and dry it a bit, to make a seductive crust. When it comes to steak, you want an even sear from edge to edge, no grill marks. All the tan meat in between the grill marks is undeveloped real estate. Click here to understand why grill marks are overrated, and in fact, undesirable on steak.
Smoke is a sapid byproduct of combustion, and the smoke from charcoal, gas, and wood are all different. Because electric grills don’t create combustion, even if wood chips are used, they have to sit this discussion out. What we call smoke is a complex combination of solid particles, water vapor, and other gases. Learn more about the subject by reading my article, The Zen of Wood and Smoke.
Let’s start by looking at heat. The most convincing argument for gas? Probably 90% of the world’s greatest and most expensive steakhouses grill their rare aged prime beef with gas. This is not just a matter of convenience or price. With the prices that steakhouses charge, they can afford any fuel they want. Why do so many use gas?
The main reason is that they want a dark all over sear and they can only achieve that with high heat. Many steakhouses use special broilers that can heat from above and below simultaneously at blowtorch temps. Restaurant gas broilers typically heat meat surfaces to 800°F to 1,200°F. Alas, regular burners on backyard gas grills canoccasionally deliver temps in the 500°F range. Some gas grills come with a sear burner that can get up to 900°F or more on a small portion of the cooking surface. Most sear burners are narrow and can only sear one or two steaks at a time, perfect if you’re an empty nester, but if you’re hosting the graduation party you will want charcoal. A charcoal grill can lay up to 700°F on the surface of a lot of steaks at once. A major reason to go charcoal.
Your mileage may vary significantly depending on make and model and how you have it set up. It is very hard to tell how much heat a gas grill will deliver because the manufacturers only tell you BTU, British Thermal Units, used. It is a useless number. BTU is just a measure of how much gas is used, like mpg in a car. Not very helpful if you want to know what top speed is. The number you want is called the “heat flux” which is the BTU per square inch of primary cooking surface (the secondary surface, the warming rack is not included). You have to calculate this yourself in order to compare potential heat from one grill to another.
But temp is not the most important factor. You rarely need high heat, in fact, as a rule, we cook most everything waaaaay too hot. I want you to learn to use the 2-zone system and hit 225°F or 325°F. Almost all my recipes call for one or the other of these two temps in the indirect zone. Rarely do I call for Warp 10, notable exception being when it comes to searing steaks. More meals are ruined by cooks who peg the dials for everything. Controlling temp on a gas grill is a lot easier, and temperature control is vital to good cooking, outdoors or in.
The other difference between gas and charcoal is smoke. Charcoal makes more smoke than gas, although, when lit completely, when fed the proper amount of oxygen, good charcoal produces very little visible smoke. In fact, the best tasting smoke is called blue smoke and is barely visible. If you are using gas, the smoke from combustion is rarely visible, but there are still flavorful combustion gases given off.
A lot of the smoke happens as drippings from the food hit the hot surfaces below. Meat drippings are mostly water, fat, and protein, plus whatever you have added, such as marinade barbecue sauce. When they hit the heat source they vaporize and some of that vapor condenses on the meat. Most gas grills cover the flame jets with metal plates, lava rock, or ceramic rocks that absorb the heat and radiate it, but the food is not exposed directly to flame. Drippings may hit these radiant surfaces where they are vaporized, making smoke and steam, much like charcoal. Some new gas grills have “infrared” burners which are superheated surfaces that are very close to the meat and more vapors get back to the meat with these burners.
There is also a difference in the flavor imparted by the volatile by-products given off by the burning of the charcoal or the gas. When propane combusts it makes more steam than charcoal, and that may help keep meat moist giving gas an advantage for some meats. Some cooks think the steam can be a disadvantage for some meats, hampering chicken skin from getting crisp for example. Charcoal produces more tiny particulates that land on the surface of the meat. But, smoke is not likely to significantly change the flavor of food that is cooked quickly such as hot dogs, burgers, or skinny steaks.
There is one other flavor difference of note. If you use self-igniting charcoal or charcoal fluid to start a charcoal fire, there can be an unpleasant petrochemical smell during ignition and it can get into the food. Yuk. For this reason you should use a charcoal chimney, a torch, or an electric charcoal starter. I strongly recommend the chimney because it is faster and easier and needs no outlet.
If you use your grill for long low and slow smoke roasting, there is a more noticeable difference in flavor. The combustion gases from charcoal when mixed with smoke from wood chips or chunks makes a distinctive flavor typical of traditional Southern barbecue. On a propane grill, the flavor is a bit more bacon-like.
Here you can see two slabs of St. Louis cut ribs cooked at the same temp side by side with Meathead’s Memphis Dust only, no sauce. The one on the left was cooked with charcoal with wood chips for flavor. The one on right was cooked with gas and exactly the same amount of chips by weight. The charcoal ribs had a deeper smokier fireplace scent and flavor. The gas ribs had a better pork flavor with hints of bacon and they were moister. Which was better? Taste is a matter of taste. I loved them both. But here’s another fact worth noting: Nowadays barbecue restaurants are springing up like mushrooms after a rainstorm and many of them are making incredibly good low and slow ribs, pulled pork, and beef brisket. The vast majority of them are using large smokers that use natural gas to produce their heat, and they burn logs for smoke.
That said, most barbecue competitions forbid cooking with gas because it is too easy, and almost all the top pitmasters use logs or charcoal, although in recent years pellet smokers have taken a fair share of the prize money. This is an anomaly that nobody has ever been able to explain to me satisfactorily: Pellet smokers are by far the easiest to use. They plug into the wall and have a thermostat. All you have to do is feed the pellets and meat, and start drinking.
When it comes to fast direct heat grilling, the fact is that, if all things are equal such as cooking temp, most folks can’t tell the difference in the taste between charcoal and gas grilled food. That’s a big if. Because most gas grills cannot achieve the same high heat as charcoal without a sear burner, charcoal is superior for getting that great dark crust on steaks that is much more flavorful than tan meat. In fast cooking the smoke doesn’t have much of a chance to flavor food. If you use strong marinades, and sauces, you will never notice taste differences especially because they hamper browning. You may think you can, but blind tastings have shown that you probably can’t.
When it comes to low and slow cooking and smoking, the taste differences are noticeable to a trained taster, but both taste wonderful, just different. So if there is little taste difference, the choice comes down to functionality. That’s why I own both.
Charcoal grills: Pros and cons
Why we love charcoal grills. Charcoal purists are vehement and border on snobbery. They who would never ever never no how no way own a gas grill. I am sure they will be the ones responding to this thoughtful treatise with equally thoughtful responses like “you’re an idiot, Meathead”.
But as we have seen, from a taste standpoint, they do have a point. The best reasons to buy a charcoal grill is that charcoal can get hotter than standard gas grills without sear burners, and heat is what you need to get steaks and lamb chops crisp on the outside and red or pink on the inside. In addition, charcoal,especially before it is fully lit, emits stronger smoke flavors that impact food more the longer it cooks. When fully lit and ashed over, and for short cooks, it produces less smoke flavor. But that smoke flavor is still soooooo gooooood.
If you use a lot of coals or if the coals are raised close to the cooking surface, they can blast food with up to 700°F or more. When I get my hands on top quality lamb or beef, I use bricks to raise the charcoal grate on my Weber Kettle to within 1″ of the meat and the result looks and tastes as good as anything you can get at a white tablecloth steakhouse.
The down side. Charcoal is dirty to handle; it can be hard to light; it takes about 15 minutes longer to get up to temp; there can be flare-ups that can burn the food and flareups may be a health risk; it is hard to tell what temp you are cooking at; the temperature cannot be turned down rapidly; during long cooks it slowly loses heat and you need to add more charcoal; if you don’t give it enough oxygen it can deposit soot all over your food; charcoal grills rarely have rotisseries; and there is a lot of ash to clean up after. In addition, there are two different kinds of charcoal and many brands to chose from. Briquets, which are made from charcoal and binders, or lump, which is pretty much just hardwood burned down to charcoal.
Most of these problems are easily surmounted if you know how: If you use gloves, shovels, or tongs, you need never handle raw coals. If you keep the charcoal dry and use a chimney, getting hot coals is easy. If you push the coals to one side of the grill and set up a 2-zone cooking environment, fatty meats like chicken skin do not drip on the coals and flare up, and even if there are flareups, a squirt gun can contain them. And cleanup of ash is easier with some of the one-touch grills or grills that have removable ash trays.
The most important part of any cooking, indoor or out, is regulating heat. To do that you need a reliable oven thermometer, and a little know-how that takes practice, patience, and persistence to acquire. Alas I have never seen a charcoal grill with a half good thermometer, and even then the excuse for a thermometer is usually mounted in the dome, not where it is needed, near the meat. The temp in the top of the dome can be very different at meat level, and I rarely plan on eating the dome, so measuring the temp there is just plain wrong.
Since charcoal grills do not have temperature dials to raise or lower temp, it is important to learn how to set up a 2-zone fire which helps you regulate heat by moving meat from the hot to the medium zone, and learn how to control the energy of the fire by closing off the oxygen intake vents. They are your temperature dials.
In short, cooking with charcoal can yield superlative results if you calibrate it and practice. The high heat is perfect for red meats, and if you learn your instrument, it will reward you handsomely. It is not intuitive and brainless, but there is little it cannot do when you achieve mastery, Grasshopper.
Charcoal devotees claim it is the flavor, but for me, a lot of the fun is the ritual and the thrill of playing with fire.
Gas grills: Pros and cons
Gas grills sales passed charcoal grills in 1994 and now almost 60% of all grills sold are gas. It is easy to understand why.
Why we love gas grills. Gassers offer convenience and control. Those two words alone cinch the argument for many folks. They are easy to start, they heat up within 10 to 15 minutes, they hold temperatures steadily yet we can crank them up and cool them down rapidly, they can be configured for indirect and multi-zone cooking, and they are easy to clean. If it’s Tuesday, you’re late getting home from work, and you need dinner ready in an hour, a gasser can do it. Low to mid-price gas grills typically have a top end of 300°F to 400°F. More expensive grills with sear burners and double layered hoods can get up to 500°F or so and newer high end models with sear burners can get as hot as charcoal, perhaps 700°F to 900°F.
Temp control. Although they excel at holding a steady temp, they are not perfect. A dial setting of 1 may equal 275°F on a 70°F day, but it can be 225°F on a cool, windy, or rainy day. Or 300°F on a hot day. But once you get to know your instrument, it is pretty easy to manage and if it has two or more burners it is easy to have two or more heat zones. On a three burner grill you might use a hot zone for meat, a medium zone for veggies, and a low zone for holding finished foods.
Temperature measurements are very misleading because the air temp above a piece of meat, in the heat shadow, will be a lot lower than the actual temp delivered to the underside of the meat if it is sitting directly above the flame. And because most manufacturers mount the thermometer well above the cooking surface it is even more misleading. If you have the left side on hot and the right side is off for a good 2-zone setup, and the worthless dial thermometer that came on your grill is in the center, it is averaging of the two zones. You really need a probe clipped to the cooking surface next to the food you are cooking. I recommend in the strongest possible terms that you buy a good digital oven thermometer and a good digital meat thermometer. Click here for my Buying Guide to Thermometers.
Easy cleaning. Most gas grills use metal plates, lava rocks, and ceramics to radiate heat, so there are no open flames, no flareups, no ash, and cleanup is easier because drips are usually vaporized. They can suffer from carbon and grease buildups that need to be scraped or pressure washed every few months. There are also gas jets and venturis that can clog. Spiders seem to like to hide down in the tubes, and I have even had to dig a wasp’s nest out of one.
Some people discard the lava rocks or ceramics every year. My brother-in-law makes the world’s finest swordfish on a crappy old gas grill with lava rocks he has been using since they were harvested in the last ice age. Some of his lava rocks have begun to disintegrate and there are gaps where bare flame slips through to lick the meat. I have never been able to come close to his swordfish on all my fancy toys.
Accessories. Gas grills usually offer a wider range of accessories. Most are set up so you can easily attach a rotisserie accessory and many come with side burners so you can keep sauces warm or cook side dishes. You can get night lights, side tables, spice racks, storage drawers, and there’s probably even one with a iPod player.
Infrared and sear burners. As we’ve discussed, the biggest problem with gas grills is that only the top end models get hot enough to get a steak brown and crunchy on the exterior without overcooking the interior. Many of the more expensive gas grills now come with sear burners. Alas, most sear burners are only big enough for one or two steaks at a time.
Smoking. Some high end gas grills also have smoke boxes for wood chips, but for most gas grills you need to make foil packets or put pans of wood down under the cooking grate near the flame. Even though it is not recommended, I often throw large chunks of aromatic woods right down near the burners on my gas grills. Alas, most gas grill lids do not seal well, so a lot of the smoke is lost and more wood is needed than on a tight grill.
Safety. Gas is explosive. It can be dangerous if you don’t handle it properly. ESPN host Hannah Storm was severely burned in December 2012 when she tried to ignite her propane grill after the wind blew the flame out. Unbeknownst to her, the gas continued to course through the jets and pooled in the lower chamber because it is heavier than air. When she hit the spark button, it exploded in her face. Windblown flameouts happen on some grills but it is hard to predict which grills are susceptible to the wind.
Price. Because the mechanisms are more complex, gas grills tend to be more expensive than comparable charcoal grills, assembly of new gas grills is more complex than charcoal grills, and there are more parts to break and be replaced. As for fuel cost, it is hard to compare the two. Charcoal is often on sale, especially in spring, and propane fluctuates with petroleum prices. Either fuel is minor compared to the food.
Environmental impact. Charcoal is made from sawdust from saw mills that would other be wasted while propane is a petrochemical that has to be extracted from wells. Charcoal produces white smoke, gas produces invisible smoke, but there are still plenty of combustion gases from propane.
Types of gas. With gas grills you have your choice of liquid propane or natural gas. LP comes in steel tanks. If you have an LP grill you should always have a full backup tank on hand. Nothing is more annoying than setting a chicken on the grill, hopping on the lawn mower, and returning in 30 minutes to discover that the tank ran out and the bird is still raw.
Natural gas is mostly methane. It must be delivered to the grill by a pipeline from your house so a certified contractor will be needed to do the installation and the grill must be parked in a permanent location. Propane grills cannot be hooked up to natural gas without an adapter kit and the regulator may need to be adjusted. Some grills come with adapter kits, some sell them as options, and some cannot be adapted. Natural gas is cheaper than LP gas and you never have to worry about running out, unless you don’t pay your gas bills.
Which to buy?
Which to buy? I have both gas and charcoal. Almost all my birds, fish, veggies, pizzas, and breads go on my LP gas grills, almost all my red meats go on my charcoal grills. If you’re starting out, and you want no fuss no muss, go gas. If you can afford it, get an infrared burner and a side burner.
If you’re willing to put in a bit more time to gain mastery of your tool, then go charcoal, and look for one that let’s you raise and lower the coal.
Or you could buy one of the new combo grills that do both, but the ones I’ve seen so far do neither function properly. But I’ll bet we see better combos in the future.