Grilling: Is it safe? Is it risky? Part 2

My interview of Don Matesz about the risks of grilling stirred up more questions and more reflection, a good thing. I myself had some questions about how paleo man cooked meat. Before interviewing Don I thought that we must certainly be adapted to grilling and that cooking a carcass on a spit (sometimes referred to as roasting) must have been a widely practiced method of preparing dinner. Yet, I also recognized that a large body of research has pointed to the production of carcinogens in grilled meat.

Good questions
Some of you questioned the idea that paleo man could have baked, roasted, steamed, and boiled meat. Where was the proof for this? You wanted references for this claim. You thought it seemed more plausible that meat was cooked over a spit (granted, it could be considered roasting, but the meat gets the same "charred" outside). After all paleo people would not always have had access pots and pans to cook in. Who wouldn’t just build a fire at the most recent camp site after a hunt and start cooking.

Some of you thought our ancestors probably suspended their meat over an open fire with the proverbial pointed stick, which sounds pretty similar to grilling, right? Some of you wondered what I meant by grilling since people often use different terms for the same technique or the same term to mean something altogether different. Photo right: Rachel Albert, © copyright 2009.

Semantics?
I learned from one of my readers who used to live in the UK that what Americans call grilling (i.e. cooking over flames/hot coals), the English call barbecuing (perhaps other English-speaking countries like Australia do the same?). To further complicate matters, what Americans refer to as "broiling" (i.e. cooking under a heat source), the English call "grilling." So my post about the hazards of grilling confused one reader who thought I was referring to what we, in the U.S., call broiling. She had no idea what it meant! It also turns out that the book used by the person I interviewed for the original grill post (The Paleolithic Prescription) used the term "roasting" to refer to cooking over a spit.

Does a grill pan grill?
At least one of you wondered about the wisdom (and possible risk) of using a grill pan or griddle pan (i.e. where food is in direct contact with a very hot surface with little oil) on top of the stove. Are the risks the same as frying or as grilling/barbecuing? What about griddle pans with ridges that leave black stripes on the food?

I don’t have a definitive answer however I would think it’s less risky since it doesn’t suspending food on a rack above a fire, so there’s no risk of fats dripping from the meat, falling onto a fire and producing aromatic compounds that would rise up into the meat as with grilling. However, I think it’s still wise to control the heat to avoid excessive smoke, which you have to breathe if you’re using a grill pan indoors, and  blackening of the food. If your kitchen is filling with smoke, you probably need to turn the high down.

Photo right: Rachel Albert, © copyright 2009.

Perhaps producing grill marks (searing the surface), and then reducing the heat would reduce the production of harmful compounds. How black you let the food get, how done you cook the meat (remember well done is more risky), how often you eat this grill-marked food, and whether and how many colorful green leafy, orange, and yellow or red vegetables, and fruits you eat with it would also affect the level of risk.

How do you grill with a drip pan?
I received another question about in response to my mention of grilling with a drip pan. “How do you put a tray under the meat that you're grilling? If the pan is placed under the grate, then it's blocking the flames, right? If above the grate, you're not really grilling. Good question.

Direct heat
For this I referred to About.com. Here I learned that there are two methods of grilling. One uses direct heat, the other uses indirect heat. “Direct Grilling is the most basic and simple way to cook. Foods are cooked, or grilled, directly over the heat.” Whether you cleave the lid up or keep it down is but a variation on the theme. The author, Derrick Riches, says “Direct cooking is the oldest method of cooking. You can do it with a piece of meat, a stick and a fire. It is the direct exposure to the heat that cooks the food.” By this definition, cooking meat in a grill pan would be cooked with direct heat. For more on this, click here.

Indirect heat
Mr. Riches explains that “Indirect Grilling is more similar to baking than direct grilling.” For this you build a fire “off to the side of where the cooking will take place. If you think of a typical gas grill, imagine having the burner(s) turned on, on only one half of the grill. This is the heated side. You then place the food you wish to grill indirectly on the unheated side and close the lid.” Using this technique, the food is cooked by convection and radiant heat, rather than direct heat. “Since the food is not being exposed to direct heat from the burners it will cook more evenly and be less likely to burn on the exposed side. Of course this also means that it will cook more slowly.” To read more about this, click here.

“So what do you do if you have a small gas grill and only one burner. Well one of the tools you need for indirect grilling is a drip pan. This can be a heavy cast iron pan or a disposable aluminum pan. This pan sits under the cooking grate where you plan on doing the cooking. If you have a one burner grill then the drip pan should go in the middle with the food directly over it. The drip pan diverts the rising heat and creates the space you need for indirect grilling. The drip pan also catches all the drippings from the food and helps keep your grill clean,” says Riches.

Indirect grilling is particularly good for foods that will easily burn on the surface before they can cook through to the middle (e.g., cuts of meat more than 2-inches in thickness, such as thick steaks or roasts, poultry, roasts, etc.) Read more below about using a combination of direct and indirect heat.

Photo right: Rachel Albert, © copyright 2009.

Combination cooking: direct and indirect heat
Perhaps you've cooked chicken or fish over the grill, seared both sides, then moved it to higher racks, away from the fire, to complete the cooking. That would be an example of cooking first with direct heat, then with indirect heat. I've done that.

When I grill, whether I use only direct heat or a combination of direct followed by indirect heat, I preheat the grill on high (covered). Once I've placed the food on the grill, I reduce the heat to medium-low (I never leave it on high) and close the lid. It takes longer to produce grill marks and to cook meat to rare or medium rare and chicken until the juices run clear (for dark meat) or until the same color inside and out (for breast meat).

Sometimes, if the chicken, thick cut of meat, or fish is almost, but not quite, done I will turn off the heat and leave the lid of the grill closed, allowing the residual heat to complete the process; this last step would be an example indirect grilling. It saves fuel and reduces the amount of time the meat is exposed to fire.

On further reflection
I emailed professor Don Matesz to see how he would reply to the comments I received after posting the interview that contained his evolutionary perspective on grilling. He graciously considered the questions and pondered the issues. Here’s what he said:

“You all raise interesting points that make me think. According to Eaton and Konner's book The Paleolithic Prescription, baking, roasting (cooking on a spit is considered roasting), steaming (using green wood and leaves lain over coals, or water splashed on hot stones and coals), and boiling (using hot rocks to heat water in a receptacle) are the main cooking techniques among recent hunter-gatherers.

“I don't know with certainty which method H-Gs favored. I have read that Australian Aborigines cook wallabies by this procedure:

1. they make a fire in a depression in the earth and fill it with stones and shells, atop of which they place green branches.
2.  throw the carcass right on those branches to singe the hide for 5-10 minutes, after which they remove the fur
3. gut the animal, then cook the organs right on top of the stones and coals
4. put the carcass on the hot stones and ashes, fill the carcass with hot stones, cover it with paperbark and sand, and roast

“You see, they don't just put it on a stick over the fire. 

“Now, I didn't think of it this way before, but I now have to admit that steps 2 and 3 resemble grilling and will impart to the meat a flavor similar to grilling.  So I was misled by Eaton and Konner on that point.  However, the cooking on coals occurred only briefly.   As I stated in the interview, the risk associated with grilling seems most tied to grilling to well-done.

“I think holding meat over a fire on a stick would apply much less intense heat than a modern grill, since the flame is open, not enclosed in a receptacle with a lid and a flue that allows the food to be cooked over a fire while in an enclosure. Using pit cooking as described above, as soon as the meat was covered, the fire would smolder due to lack of air, creating a much lower temperature than grilling on modern grills.

“Holding over an open fire on a stick strikes me as more like smoking than grilling, where temps might only reach 150 to 250 degrees F, especially if there is wind. Also, realize that if you put meat on a stick (wood) you can't hold it as close to the fire as you can with a metal grill because the stick could catch fire.

“The other evidence still seems to point to adverse effects of grilling, especially the finding of higher amounts of mutagens produced by grilling in cancerous tissues. However, I do think it is possible that other aspects of the H-G lifestyle protected them from what little exposure they had to cooking by-products, particularly sun exposure.

“Those who think I gave misinformation about grilling by-products can look at the links provided. 

“Thank you all for your comments and know that they will stimulate me to think this problem through again.  Like many people, I like the smoky flavor of grilled meat, and eat grilled food several times per month.  Perhaps I missed something else and will update my views if I find I have made other mistakes.”

How’s that for thorough? If you have more questions or comments about this, please post your comments below. I read and consider all of them. If you have ideas for other topics you’d like to see me cover, send your ideas my way. I look forward to reading them. If you want to read more of Don's evolutionary perspectives on diet, nutrition, and health, check out his blog.