Charcoal briquettes are almost always made with corn starch. Kingsford, the largest manufacturer of briquettes in the US only uses corn starch. Even if wheat starch is used, which is rare, we could not find any evidence that it would contaminate foods with gluten. Charcoal is made with 90 percent hardwood and coal. The other 10 percent is made from minor ingredients – binders, an accelerant and an ash-whitening lime to let you know the briquettes are hot enough. The starch binder is only a very small part of the charcoal and in the rare case where wheat starch is used, gluten protein would only be a tiny portion of the starch.
Mark Kantor, PhD, an associate professor of food sciences and nutrition at the University of Maryland said since the briquettes should not come in contact with the food it is very unlikely that food would be contaminated with trace amounts of gluten in the starch. He said when the briquettes are burned it is unlikely that the smoke would contain any significant amount of intact gluten because the protein would be denatured or incinerated.
We also asked Steve Taylor, PhD, co-director of the Food Allergy Research and Resource Program at the University of Nebraska and he said that although he is not familiar with any studies on gluten in charcoal briquettes, he doubts that the smoke would contain any detectable gluten.
So the evidence really stacks up against worrying about gluten in charcoal.
You could face some risk of cross contamination at your holiday barbecue from gluten-containing foods prepared on the same grill. If, for example, buns were toasted on the grill before your burger was placed on it some crumbs might remain. You should ask that your food be prepared before anything that might contain gluten. (Although many marinades are gluten free, some could contain soy sauce or malt vinegar, and could also contaminate a grill. Remember distilled vinegar is gluten free and the only kind you have to worry about is malt vinegar, which is usually made from barley.)
Everyone at Gluten-Free Living hopes this information takes some of the worry out of your weekend. And we wish a happy and safe 4th to everyone!