Grilling is one of the oldest cooking methods known to humankind. Our early ancestors’ ability to harness fire fundamentally changed what it meant to eat and live. Grilling over a flame didn’t just make food taste better. It also changed the structure of our diets and our brains. It’s no surprise, then, that the allure of smoky, fire-charred food still pulls us in today. For the home cook, the grill remains one of the most powerful and evocative tools in the kitchen (or backyard).
This blog post dives into the how and why of grilling—what makes it work, how to get the most flavor out of it, the differences between charcoal and gas, and how to avoid common pitfalls.
How Charcoal Grilling Works
Charcoal is the heart of traditional grilling. Compared to wood, charcoal burns hotter, cleaner, and longer—and it gives cooks more control over heat. That control comes down to a principle that’s deceptively simple: the draft.
Think of the grill like a chimney. As hot air rises, cooler air is pulled in to feed the fire. Stoke the flames and the hot air flows faster. Choke the fire and the airflow slows. The rate at which air moves through your grill (your draft) is directly tied to the heat your fire generates.
This balance of oxygen and heat is key. Fire needs oxygen to burn, and charcoal consumes it fast. When you adjust the vents on your grill or rake your coals around, you shape the draft and, in turn, the temperature. Too much oxygen and you risk flare-ups; too little and your fire smolders. The trick is learning how to anticipate changes, because charcoal responds slowly. Mastering the lag is part of developing what many call “the art of the grill.”
And, of course, we can’t forget the smoke. Smoke is a flavorful aerosol of tiny solid particles and liquid droplets suspended in gas. It’s what gives grilled food that craveable, unmistakable flavor. Where there’s smoke, there’s flavor.
What You Need to Know to Use Your Charcoal Grill Well
Grills are intense. Most of the heat they produce is radiant, not convective, which means it comes from glowing coals and burning drippings rather than hot air. That makes grilled food taste delicious—but also makes grilling tricky. Here are some fundamentals to keep in mind:
- Cook thinner cuts. Thick food will burn on the outside before the inside is done. Thin cuts of meat, flat vegetables, and seafood are ideal.
- Wait for the ash. Coals should be coated in a layer of ash before you start cooking. This layer moderates the heat and slows the draft slightly, making it easier to manage.
- Embrace the inefficiency. Grills waste a lot of heat. That’s normal. But without that blast-furnace intensity, your food wouldn’t develop the flavor and crust that makes grilling so beloved.
- Mind the smoke. Smoke floats when hot air carries it. Let it cool, and it sinks. The blue haze you may see is the Tyndall effect scattering light.
- Charcoal grills aren’t nonstick. At high heat, nonstick coatings would break down, so seasoning your grill grate—like you would a cast-iron pan—is a better strategy. A little oil on the food also helps, though it can cause flare-ups if overdone.
Grilling with Gas
Charcoal grills may be traditional, but gas grills offer such convenience that they have become vastly more popular. However, there are some differences between the two. For example, charcoal fires deliver more heat to the grill because they burn cooler and dirtier than gas flames do. Confusing, perhaps, but true. Essentially, charcoal grills simply radiate more heat than gas grills thanks to the red-hot coals.
Propane and natural gas burn at a much hotter temperature, around 1900 °C / 3500 °F. The main chemical reaction involved in their combustion is fundamentally different from that in glowing coals. Gas burns cleanly in flames that visibly emit only an ethereal blue light. Although the temperature inside those dim blue flames is quite high, they actually radiate very little energy.
Gas grill manufacturers understand the importance of radiant heat, and they know that clean-burning gas doesn’t produce much of it. They overcome this difficulty by converting some of the hot gases of combustion into radiant heat by placing lava rocks, ceramic plates, or metal bars above the flames. As these surfaces heat up, they emit radiant heat, but much less of it than glowing charcoal does.
As the hot gases travel from the flame to the radiating surface, they mix with cooler surrounding air. That mixing makes it difficult to raise the temperature of the radiant emitters in a gas grill to much higher than about 800 °C / 1,500 °F—a good 300 °C / 570 °F below the radiant temperature of glowing charcoal. That is a large difference in effective temperature, and it has a disproportionate effect on radiant heating power.
However, gas grills are still a great substitute for charcoal grills. They tend to heat more evenly. You get the same grilled flavor because drips of fat still hit a hot surface (typically artificial rocks or metal plates) and flare up in puffs of flavorful smoke. Gas grills offer more control over the intensity of heat than coals do—but because we use the grill only for fast searing, our grill is always turned to high.
There’s an ongoing debate about whether briquettes or hardwood charcoal produce the best grilled flavor. It turns out fuel isn’t what matters. The secret to the flavor of grilled food is the drippings.
When fat and juices, laden with natural sugars, proteins, and oils, from your food hit the coals, they combust. By catalyzing myriad chemical reactions, the intense heat forges these charred juices into molecules that convey the aromas of grilling food. These new aromatic compounds literally go up in smoke, rising back up and coating your food with the unmistakable grilled flavor.
Those flickering flames are not just for show. They’re glowing soot particles, superheated by burning carbon monoxide and oxygen to temperatures over 2900°F (1600°C). The result is that coveted grilled taste.
Pro Tips for Better Grilling
- Classic grillables like burgers and sausages have enough fat to create flavor-packed smoke. Lean cuts or vegetables benefit from a spritz of rendered fat, clarified butter, or neutral oil to replicate that effect.
- Oil the food lightly to prevent sticking. Cure fish in a brine with salt, sugar, and lemon zest for even better results.
- Cook evenly. Most grill interiors are black, which absorbs heat instead of reflecting it. Line the inner walls with aluminum foil to bounce more heat back toward your food.
- Dry your food. Moisture slows down browning. Pat food dry before it hits the grill for a better crust.
- Use heat strategically. Sear first or last depending on your cooking method. If you sous vide your food first, sear at the end to keep the crust crisp.
Grilling is part art, part science, and all flavor. The more you understand the mechanics behind the fire, the more confident and creative you’ll become. So next time you fire up the grill, try out these tips to better master the flame.
FURTHER READING
- Which Is Better: Briquettes or Hardwood?—Modernist Cuisine at Home, p. 45
- More Tips for Grilling—Modernist Cuisine at Home, p. 46
- Using a Blow Dryer to Get Your Grill as Hot as Hell—Modernist Cuisine at Home, p. 47
- Baking on the Barbecue—Modernist Cuisine at Home, p. 45; Modernist Cuisine Vol. 2:13
- Where There’s Smoke, There’s Flavor—Modernist Cuisine Vol. 2:12
- A Look Inside the Grill—Modernist Cuisine Vol. 2:9
- Charcoal vs. Gas—Modernist Cuisine Vol. 2:10
- The Sweet Spot of a Grill—Modernist Cuisine Vol. 2:14
- Making Your Grill (or Broiler) Shine This Summer
- Why Food Goes from Almost Done to Overdone So Quickly on the Grill
- How to Make Pizza on an Outdoor Grill This Summer
- For a Great Summer Feast, Cook Ahead, and Bring Extra Fat
- Cooking Meat on a Grill
- Pressure-Rendered Chicken Fat