"If there's one grilling tip to remember this Memorial Day weekend, it should be this: Flame is bad."

"Flame does nasty things to food," food historian and science guy Alton Brown tells NPR's Scott Simon."

"[Flame] makes soot, and it makes deposits of various chemicals that are not too good for us. The last thing you really want to see licking at your food while it's on a grill is an actual flame," says Brown, who is known for kicking up the science on various Food Network shows." 

"Brown is also a grilling enthusiast ('I grill, therefore I am,' he says), with seven grills at home. So when you're talking about backyard cookouts with Brown, make sure you know the difference between grilling and barbecuing. Barbecue, Brown notes, is 'a meat product produced by long, slow cooking and exposure to a good deal of smoke, and is usually some part of a pig.'"