Gas grills are revered for the instant gratification they provide, but many purists feel that they deliver insufficient smoke flavor. In an effort to amp up the volume, so to speak, manufacturers recommended adding a layer of lava rocks to the base of the grill. In recent years, however, this practice has been discontinued. If you’ve ever seen one of the older models in action, you might be wondering—why don’t gas grills use lava rocks anymore?
A Brief History of Lava Rocks
A lava rock is a form of igneous rock, meaning it was created from the magma or lava of a volcano.
Magma is the term that geologists use for lava when it’s still inside the volcano; once it flows outside, it’s known as lava. Technically, however, both terms refer to the same material. Lava rocks can be formed from either version, depending on where the sample was when it was found. But what does any of this have to do with your gas grill?
As you know, grilling is all about flavor, primarily smoke flavor. Since the flame jets on a gas grill are incapable of providing this, lava rocks were introduced as a creative solution.
In theory, when the drippings from the grilled meats fell onto the layer of rocks below, they would sizzle and create smoke. This smoke would then drift upward to infuse the meat with that prized, authentic flavor.
Igneous rock has a porous surface that allows them to retain heat more effectively than their sedimentary and metamorphic counterparts. They also have an impressive durability, an appealing quality for any tool that’s used in cooking applications. For more information on lava rocks and why they were used, take a look at Why Do You Need Lava Rocks for Gas Grill, below.
While some companies offered gas grills that were designed specifically to hold the stones, most existing grills could be converted easily enough. Many manufacturers even sold the lava rocks themselves as part of a combination package.
Why Do You Need Lava Rocks For Gas Grill?
Aside from the flavor factor, there are several reasons why this practice became popular. Here are the most common ones.
Heat Retention and Distribution
The convenience of gas grills gives them a huge boost in the popularity department. Still, even their fiercest advocates will admit that when it comes to heat retention, they don’t hold a candle to charcoal-fueled units. Because of the direct heat from the flame jets, preparing food on gas grills may also result in “hot spots” and uneven cooking in general.
In this regard, lava rocks offer a helping hand. As the stones warm up, they retain and reflect back that ambient heat. This allows the cooking chamber to maintain a consistent temperature, so the entire cooking grid is available for use. When you add lava rocks to the gas grill, you can prepare more ingredients in a shorter period of time.
Moreover, the chamber will continue to hold its heat for a while even after the flame jets are switched off, which is a big help when it comes to indirect cooking techniques. This benefit also cuts down on the propane bills.
As we mentioned, lava rocks can last for a long time when they’re treated properly. This led many people to believe that they were a good investment, since they wouldn’t need to be replaced very often, if at all.
Since the rocks are routinely exposed to extreme heat, their sturdy nature is a definite plus. Unfortunately, there are two sides to this story, as you’ll come to learn.
Lava rocks are porous, meaning that their surface is made up of pockmarks and crevices that readily absorb liquids, including fat. When the drippings collide with the rock, they soak into the surface instead of splattering in all directions. In the short term, this prevents the kind of flare-ups that can ruin your dinner and possibly your health. In the long term, however, this quality will produce the opposite result, which is why lava rocks are no longer considered a favorable solution.
Why Don’t Gas Grills Use Lava Rocks Anymore?
So, do you need lava rocks for gas grill cooking applications? Not really. In fact, we would advise against the practice, as would most professionals.
Given the manner in which they were forged, lava rocks are capable of withstanding great heat. When the hot drippings touch them, they vaporize instantly, which does produce an impressive burst of smoke. As we mentioned, the rocks are also capable of absorbing a great deal of this grease, which makes it easier to clean the grill after each use.
However, the drippings leave behind a residue that’s nearly impossible to remove. Since lava rocks are porous by nature, there’s no way to get all of those fat deposits off the surface. After a while, this buildup will attract harmful bacteria, thereby increasing the risk of food poisoning every time you fire up the grill.
In addition to being unhygienic, these accumulated drippings can lead to flare-ups, which are a quick way to ruin a good barbecue. While you want grilled food to taste of smoke, excess flames will result in charred food, which poses a cancer risk. It’s not very appetizing, either.
We should point out that these issues could be avoided if the lava rocks were cleaned after each use. As we pointed out, however, some buildup is inevitable, even with frequent washings. That means the rocks would have to be replaced after six months to a year, depending on how often the grill was used.
Alternative Solution: Ceramic Briquettes
A briquette is a compact brick of combustible material that can be converted into a unit of energy. They can be made from sawdust, charcoal, or even inorganic materials, as long as they’re an efficient fuel source. In the case of ceramic briquettes, they’re fashioned out of—you guessed it—ceramic dust.
The reason pitmasters prefer ceramic briquettes to lava rocks is a simple one: They don’t absorb grease the way lava rocks do. That makes them much easier to clean, which will reduce the risk of flare-ups in the long run. Ceramic is also an efficient heat conductor, so you don’t have to worry about hot spots.
Most importantly, ceramic briquettes will last a long time, even if they’re used on a regular basis. As a result (and likely owing to the fact that lava rocks have fallen out of favor), they’re also more expensive.
How To Use Ceramic Briquettes in a Gas Grill
1. Make sure the grill itself is clean and free of residue. Wash the cooking grates in hot soapy water and brush off the burner tubes. Use a stiff-bristled brush or putty knife to scrape out any grease or carbon buildup.
For a tutorial on how to deep-clean a gas grill for seasonal maintenance, take a look at this video demonstration.
2. Check to make sure that the gas ports are open and free of any blockages. The heat box itself should be well-ventilated.
3. Line the firebox with a few sheets of heavy aluminum foil. This will help to prevent residue from building up in the bottom while boosting heat retention.
4. Add a few scoops of gravel to the aluminum lining. In addition to being aesthetically pleasing, the gravel will allow the firebox to retain more heat.
5. Add the ceramic briquettes. Arrange them evenly, so that all of the briquettes will be equidistant from the cooking grates. Don’t stack them too high, or you’ll run the risk of burning your food. At the same time, don’t keep the stack too low, or the briquettes won’t be able to do their work properly.
6. Light the gas grill and close the lid. Allow the flames to burn until the briquettes turn red-hot.
7. If your grill has a built-in thermometer, use it to check the internal temperature of the grill. Once it’s reached your desired temperature, you’re ready to start cooking.
How To Clean Ceramic Briquettes
Ceramic briquettes are built to last, but they still require proper care and maintenance. If they’re not cleaned on a regular basis, they might deteriorate. Dirty briquettes won’t distribute heat as evenly, which defeats their main purpose.
When it’s time to clean the briquettes, place them on the grill and set the flame jets to low. Replace the lid and wait about 15 minutes. If you do this regularly, this step will be sufficient for removing all the dirt and residue.
If the briquettes have gained a layer of grease or soot that won’t come off after a regular cleaning, try soaking them in white vinegar for about 30 minutes. Scrub them with a stiff-bristled brush to remove any lingering residue. Rinse them well and let them air-dry before attempting to use them again.
When the vinegar trick no longer works, consider replacing the briquettes. If you continue to use them after they’ve outlived their functionality, they can impart a strange flavor to your grilled food.
Yes, ceramic briquettes can also be found in a variety of flavors, similar to lump charcoal or pellets. When the briquettes are heated, the smoke flavor is activated. Choices include mild woods such as apple and pecan, as well as more intense flavors like hickory and mesquite.
Although we’re huge proponents of authentic smoke taste, we find that these flavored briquettes have an artificial quality. We would recommend avoiding them whenever possible. Instead, use regular ceramic briquettes for their intended purpose, which is to retain and distribute heat throughout your gas grill.
Built-In Ceramic Tiles or Bars
These features, which are included on some premium gas grills, play a similar role as lava rocks and charcoal briquettes. Depending on the brand, they might be called “Flavorizer Bars,” “Flav-R-Wave,” or something similar.
Ceramic tiles are outfitted with holes or rivulets that allow the drippings to flow right through, thereby minimizing flare-ups. The openings also provide enough ventilation to provide the cooking chamber with steady, even heat. If these grills fit into your budget, we would recommend giving them a closer look.
Frequently Asked Questions
Are lava rocks ever used in charcoal grills?
The whole idea behind lava rocks was based on the gas grill and its inability to provide authentic smoke flavor. Charcoal grills, on the other hand, are widely considered to be superior in this regard. Charcoal is also more effective when it comes to heat distribution and retention.
Moreover, charcoal fires have to die out gradually—you can’t shut them down at the flick of a switch, the way you can with a gas-powered flame jet. That means the lava rocks will stay hot for longer periods of time, causing them to break down faster.
In short, there’s no reason why you should add lava rocks to a charcoal grill. It won’t do any harm, but it offers no real benefit either.
How often do lava rocks need to be replaced?
If you do choose to add lava rocks to your gas grill, they should be replaced every year or so. Bear in mind that this time frame is only valid if the stones are cleaned regularly.
How do you convert a gas grill to hold lava rocks?
To make a gas grill suitable for lava rocks, first remove the original heat tents or barriers that came with the unit. In their place, install a new grate, one that fits neatly into the designated space. Pour in a layer of lava rocks and arrange them so they’re evenly distributed. They should be spaced so that they completely cover the burners, but far enough apart to allow for decent airflow.
The new grate should sit right on the brackets that held the original heat tents. To find the right one, take your grill’s measurements beforehand.
Can lava rocks damage the grill?
Yes. Lava rocks form a porous barrier, which doesn’t provide sufficient protection to the base of the grill. As a result, grease and oil are allowed to settle along the burner rods, leading to an eventual case of burner rot. Again, this issue can be mitigated with regular maintenance, but it’s an issue to be considered nonetheless.
Why don’t gas grills use lava rocks anymore? In short, they’re no longer recommended because their long-term risks outweighed their benefits. Ceramic briquettes can deliver similar results, along with an easier and more efficient maintenance routine.