Lava/Pumice/Ceramic/Metal
Gas Grills require a diffusing material between the meat and the direct heat produced by the gas. This material, in addition to diffusing the heat, will contribute to the amount of smoke generated and also protect the burner elements. Common substances used may consist of lava rocks (less common), compressed pumice rocks (or briquettes), metal plates or ceramic diffusers. The build-up of grease on any of these diffusing elements presents a potential flare-up hazard!
What is the Difference Between Ceramic and Metal Diffusers? - Ceramic Diffusers can come in all shapes; usually your grill will have a bag of material such as this to spread on the lower grate to help prevent flare-ups.
There are several types of Metal Diffusers:
Cross-Bar Diffusers - These diffusers are perpendicular v-shaped bars (^) which eliminate much of the grease and drippings reaching the flames.
Stainless Steel Diffusers - These diffusers block some of the grease and drippings which can lead up to flare-ups, though the large square holes can still allow some drippings through.
Stainless Diffuser Pan - This pan covers the entire cooking surface, below the grates and does not allow any grease or drippings to reach the fire. Another nice feature of this design is that it allows for easy cleanup as well as a place to put the wood chips when you want to add some "smoky flavor" to your food.
Food Grids - The real action when cooking on a gas grill occurs with the Food Grid. This grid covers the entire cooking area above the diffusing materials and burners, and is where the entree is actually cooked. The food grid is usually constructed of:
- Round stainless steel bars.
- Stainless steel plates.
- Stainless plates or bars that have been covered with ceramic material.
- Cast iron that has been covered with ceramic material.
The better grills also provide one or two secondary grids that either rest on top of the primary grid or are attached to the hood. You can use the secondary grids for potatoes or other items where direct heat may be a concern. Make sure secondary grids are removable in order to accommodate larger pieces of meat, such as a turkey or a large brisket.
Heat Control Valves - Gas Grills utilize heat control valves for regulating the inside cooking temperature. The most preferred method is to have one control per burner. Typically, the “HIGH” setting would be for burning old food and grease from the rack and the lava or pumice rocks. The “MEDIUM” is used for most types of cooking, while the “LOW” setting is most often used for warming foods. Regulate the temperature of your gas grill through the use of the heat control valves, as reflected by the thermometer.
