Some think this is a debate of preference like paper vs. plastic or iPhone vs. Blackberry. Actually, there is some science in the chemical reactions that take place when food is grilled over charcoal compared to food grilled over a gas flame.
A blind taste test done by the Good Housekeeping Institute in 1998 found that tasters could not detect a difference between hamburgers and boneless chicken breasts grilled over the two fuels. However, the tasters could distinct a flavor advantage in sirloin steaks grilled over charcoal. The Good Housekeeping Institute attributed this difference to the fact that steaks take twice as long as hamburgers and chicken breasts to cook so they have more time to absorb the charcoal flavor.
According to a study from Vanderbilt University meat grilled over a charcoal fire has a plumper texture because the flame coagulates the meat’s surface proteins sealing in the juices. The study also found that wood gases that remain in the manufactured charcoal impart a smoke flavor to the food.
The study also revealed that the heat from a gas grill contains moisture which “steam distills” meat opening the surface pores and releasing juices. The study says the meat takes on a “floppy” texture.
Cooks Illustrated magazine also conducted a comparison in 2004. They found that food cooked over charcoal had better browning and searing than it’s gas grill counterparts. They also cited a distinct smoke in the charcoal grilled foods that was lacking in the gas grilled meats.
The winner: Smokey Flavor
Because people tend to prefer a smoke flavor gas grills often have a small drawer called a smoker box where wood chips are added to impart flavor. The type of wood chip used is a matter of preference in deciding between a heavy wood and a fruit wood.
If your grill doesn’t have a built-in smoker box smoker trays can be added or you can simply wrap the soaked wood chips in a heavy-duty foil pouch.
In another attempt to get gas grilled meat to resemble meat grilled on a charcoal grill, gas grill manufacturers offer grills with infrared technology. A typical infrared grill can easily reach over 500 °C (900 °F) in matter of second even without closing the hood, allowing you to sear steaks right away. Grilling enthusiasts claim food cooked on an infrared grill tastes similar to food from charcoal grills because when coals are burnt, they also emit infrared radiation.
While restaurants tend to use gas grills, almost all competitive barbecuers use charcoal grills. Restaurant grills typically reach temperatures of 700 degrees which is a temperature the average gas grill can not reach. Charcoal grills can reach 500 degrees also higher than the typical gas grill.
Grilling enthusiasts all seem to agree that lump charcoal is a better choice than briquettes. Briquettes are made with sawmill waste and often contain chemicals and binding agents. Self-igniting charcoals contain paraffin and petroleum products that most agree taints the food’s flavor. Some believe that lump charcoal made solely from hardwood is best because charcoal made with bark could include insects or mold.
In conclusion, because most gas grills cannot achieve the same high heat as charcoal, charcoal is superior for getting that great dark crust on steaks and a nice smokey flavor sure to please the most discerning palette.