Lava rocks are used in grills, primarily gas grills, as a way to retain heat during the cooking process. Created from volcanic blasts, lava rock can be purchased at home care centers as well as at some grocery stores during the summer. Proper care, use and maintenance of lava rocks can create an ideal grilling experience.
Heat Storage and Cooking Area
By nature, lava rocks are porous, with small holes throughout the rock. This makes them an excellent heat-holding source, allowing you to distribute heat throughout your grill, into areas where the gas flames may not otherwise reach. The lava rocks absorb the heat from the gas flame and hold and distribute it to any area the lava rocks are placed, creating a more widespread cooking area as well as greater heat throughout the grill.
Grilling is a naturally low-fat cooking method that produces a lot of flavor. However, to reduce potential exposure to harmful carcinogens that result from charring and smoke exposure, regular occurrences in grilled foods, keep your lava rocks fresh. As the fat from your food drips down onto the rocks, the excess is stored in the rock's pores, leading to extra smoking as time goes by. The smoking fat not only changes the flavor of your food, it contains harmful carcinogens. However, lava rocks can also be used to reduce the exposure to carcinogens from grilling because of their high heat-holding capacity. The longer the heat is held in the grill, the shorter the cooking times, which means less exposure to smoke and carcinogens. The high heat-holding ability also means you can turn off the flame, close the lid and keep your food on the grill to finish slowly cooking or warming, without needing to expose it to a continuous flame or smoke.
Use Them In Gas Grills
Lava rocks work best as a heat distributor, and because the charcoal or wood used in charcoal grills naturally holds and distributes heat, lava rocks are generally unnecessary in charcoal grills, although they can be used. Gas grills, however, only have available heat when the fuel is lit and running. The lava rocks help sustain the heat in the grill as well as the available cooking surface, even when the fuel supply is off.
Setting Up Your Grill
Using lava rocks in your grill requires a special grate, below the cooking surface and above the flames. You can purchase a separate rock grate for your grill, or you can use the heat plates that are already in the grill to hold the rocks. While a 1-inch distance between the burners and the rocks is recommended, you can go up to 2 inches apart. You need at least 3 to 4 inches of space between the top of your lava rocks and your cooking grill. In all cases, you need to have space for air to circulate between the rocks, the heat source and the cooking grill.