The Pizza Oven -- Does it Matter?

[Stone]

(Is it worth discussing whether pizza (NY, New Haven or what-not) is from Italy or influenced by Italy? I've heard that it's really an American treat.)

[tommy]

(Is it worth discussing whether pizza (NY, New Haven or what-not) is from Italy or influenced by Italy?  I've heard that it's really an American treat.)

you mean it's not ethnic?

[201]

Mr. Toast

I almost fell off my chair when I saw Mr. Toast. No shit, true story!!!

Carry on...

Oh, and welcome to eGullet, Mr. Toast. And thank you... of course, of course. Oh man, if I drank I'd be hitting one back right about now. Nevermind, I'm going to bed if I can ever stop laughing.

[Fat Guy]

Stone: Heat is heat in one sense, but how heat is conveyed makes a huge difference. Think about the difference between cooking in a 400 degree oven, cooking on a 400 degree cast-iron skillet, and cooking under a 400 degree broiler. One is a transfer of heat from the ambient air. Air is a poor conductor of heat -- in fact it's more appropriately thought of as insulation. That's why you use convection fans to improve performance -- if you get the air moving it transfers the heat more effectively. With a cast-iron skillet, the heat is transferred by direct contact with metal or another solid that is likely to be a heck of a lot better at conducting heat than air. Insulation is not the issue. With a broiler, the heat is being radiated and that provides yet another means of transfer. Speaking non-scientifically, these are the three primary ways an oven cooks: You have your ambient/convective heat (which can be improved with a convection blower), you have your direct contact with a surface such as a stone or whatever, and you have your radiated heat as from a broiler. Does that make sense? I'm sure someone can clarify it and straighten out any inaccuracies.

In terms of pizza being from and influenced by Italy, is there really a question? Go ahead and start a different thread if you think there is.

[Jonathan Day]

I would not expect indirect heat (fuel in a firebox) to affect the flavour of pizza. Heat, as FG says, is heat. And I doubt you could burn coal directly in an oven -- doesn't coal generate toxic fumes? So my guess is that coal-fired ovens are more a matter of nostalgia. Nor would I expect wood burnt in a sealed in a firebox affect the taste, unless there were some sort of leak between the firebox and the oven itself.

But I can assure you that an oven in which wood has been burnt directly imparts a very different taste to food, and this is true whether the foods cook on the floor of the oven or in a container. I have a terra cotta "beehive" oven which you fire with wood; you then clean out the ashes and put in the food. Even cold, with the ashes brushed out of it, the oven has a strong aroma. The flavour transfer happens relatively quickly -- with a pizza as well as the longer-cooking dishes you put in after the oven has cooled a bit. I burn hardwoods, because woods like pine create too much smoke and impart unpleasant flavours.

What I don't understand is the mechanism through which it happens. We need a scientist or a barbecue expert to weigh in here.

[macrosan]

I'll bet you Heston Blumenthal knows the answers

[Fat Guy]

I bet you could just scatter some ashes on the floor of any oven, brush them out, and capture the same result.

[Jonathan Day]

Or you could add "liquid smoke" to the product. Or, as someone showing me how to make chicken-fried steak once did, sprinkle ashes from a cigarette over the pan, "for extra flavour". Both would change the flavour of the finished dish, but not in the positive way that cooking in a wood-fired oven does.

Or are you seriously contending that wood-burning ovens are a silly affectation, and that gas or electricity + ashes would have the same effect? If so, what evidence or experience or data would you bring to the table? I have cited experience making pizza in a professional electric pizza oven and a wood-fired oven. What is the basis for your bet?

[Robert Schonfeld]

If anyone has an interest in learning to cook with masonry ovens that are fired internally, I'll see if I can get one of my friends to write something here.

That would be great, Nickn. Thanks.

[Fat Guy]

Or are you seriously contending that wood-burning ovens are a silly affectation, and that gas or electricity + ashes would have the same effect? If so, what evidence or experience or data would you bring to the table? I have cited experience making pizza in a professional electric pizza oven and a wood-fired oven. What is the basis for your bet?

If the burning wood itself provides no appreciable smoking effect with a high-temperature, quick-cooked item -- if indeed the perceived flavor difference is on account of the interaction of ash, the oven's surface, and the food -- it seems pretty straightforward that, all other things being equal, you could get the effect with just the ash and not the fire. Do you see a flaw in this reasoning?

[g.johnson]

Doesn't that beg the question? Why do you assume no smoking effect.

[Fat Guy]

In a well-tended oven though, smoke would not be a part of the flavor as the oven is hot enough that the fire is burning cleanly.

For a lot of reasons, G. For one thing, nickn, who apparently participates in the manufacture of ovens for a living, said the above. In addition, this is what every expert I've ever spoken to has told me: smoking is something that takes place at lower temperatures over longer periods of time. If you review the literature on charcoal grills, for example, you'll see it said over and over again that no appreciable smoking can occur in the time it takes to grill a hamburger or a chicken breast. This information has been repeated to me by bakers, et al., many times. Has anybody been told otherwise?

[Fat Guy]

Here are some comments from the California Barbecue Association. This is no the subject of charcoal for grilling/broiling versus charcoal for barbecue. I'd suggest the theory here is similar, with the difference being the presence of ash in the oven cavity.

http://www.cbbqa.com/notes/CookingWithGas.html

[Stone]

(Referring back . . .) I certainly see the difference between the oven and the frying pan. The broiler, I'm not so sure, but that's splitting hairs. My point, however, is that in a pizza oven, it's the same heat-transfer mechanism (air) whether using gas, coal or wood.

As for smoking, I think that the BBQ analogy may not be so sound. It certainly takes awhile for the smoke to penetrate deep into a piece of meat. But not very long for it to settle on the surface and affect the taste of bread or whatever.

[Fat Guy]

(Referring back . . .)  I certainly see the difference between the oven and the frying pan.  The broiler, I'm not so sure, but that's splitting hairs.  My point, however, is that in a pizza oven, it's the same heat-transfer mechanism (air) whether using gas, coal or wood.

What's giving you trouble with seeing the difference between a radiant heat broiler and a convection oven? If you've used the two, you know they're quite different. Radiant heat is how our sun heats the Earth, for example. It's about radiating energy directly into the food. A convection oven, on the other hand, works by elevating the temperature of the entire oven cavity and moving air around to conduct the heat. Different processes.

In a pizza oven, the air is only one of the transfer mechanisms. The hearth itself is as or more important: direct contact with the oven floor is the equivalent of cooking something in a skillet or on another hot surface, and the radiant heat from the walls and roof of the oven cavity are also working to bake the pizza or bread. Air contributes too, but there are several processes in play.

As for smoking, I think that the BBQ analogy may not be so sound.  It certainly takes  awhile for the smoke to penetrate deep into a piece of meat.  But not very long for it to settle on the surface and affect the taste of bread or whatever.

But with a clean-burning wood fire, as is considered desirable in a pizza oven, there is no smoke.

[Stone]

I thought the point of the broiler was higher heat, closer to the food, from one direction. The transfer is still by heating the air. The heat "radiates" because the broiler is so hot. It's not like there's a fan or something pushing the heat out of the broiler. The oven is less-high heat, all around, but the heat still radiates from the floor and the walls. (You're right about transfer from the oven floor, but it's still the same in all pizza ovens, non?)

Re smoke: if it's a smoke free fire, you've probably answered the question about the importance of smoke.

[g.johnson]

Radiation involves heat transfer via electromagnetic radiation. It would work in a vacuum.

[Stone]

We were using the term lay-man-like.

Edit -- you smug bastard.

Edited February 26, 2003 by Stone (log)

[Nick]

Stone: Heat is heat in one sense, but how heat is conveyed makes a huge difference. Think about the difference between cooking in a 400 degree oven, cooking on a 400 degree cast-iron skillet, and cooking under a 400 degree broiler. One is a transfer of heat from the ambient air. Air is a poor conductor of heat -- in fact it's more appropriately thought of as insulation. That's why you use convection fans to improve performance -- if you get the air moving it transfers the heat more effectively. With a cast-iron skillet, the heat is transferred by direct contact with metal or another solid that is likely to be a heck of a lot better at conducting heat than air. Insulation is not the issue. With a broiler, the heat is being radiated and that provides yet another means of transfer. Speaking non-scientifically, these are the three primary ways an oven cooks: You have your ambient/convective heat (which can be improved with a convection blower), you have your direct contact with a surface such as a stone or whatever, and you have your radiated heat as from a broiler. Does that make sense?

Yep, that makes sense. Heat is transfered from warmer to cooler by conduction, convection, and radiation. The use of the skillet to illustrate conduction was good.

Heat is just heat when measured by temperature alone. But, there are also qualities to heat. For instance, when you come into a house out of the cold just coming into the warmer air of the house feels good, but if there is a fire going in a stove or fireplace the radiant heat from the fire feels even better. Radiant heat whether warming ones-self or cooking food has a quality that is distinctly different.

To this is added the ability of various materials to conduct and/or store heat aside from mass. This why (all other things equal) an oven made of one material will perform differently than that of another material. The same is true of pots and pans.

Edited February 27, 2003 by Nickn (log)

[Nick]

If anyone has an interest in learning to cook with masonry ovens that are fired internally, I'll see if I can get one of my friends to write something here.

That would be great, Nickn. Thanks.

I'll get hold of a couple of friends and we'll see what happens. The friend I'd really like to have get in here doesn't have computer or connection as far as I know. Last I heard he's living in an old bunk house in MT cooking on a one or two burner electric hot plate - when he cooks. I've also heard he's eating stuff out of a can cold. He went to culinary school probably thirty years ago and has followed a wandering path since. But, everyone that's cooked with him or eaten his cooking says he's the best. A couple of months ago he did up a buffalo roast and roasted it in a soapstone wood-fired oven. Since I heard about it here in Maine, I guess it was pretty good. I'll see if Jerry can drag him into town and get him to write something.

In the meanwhile, I'll get hold of Marcia Olenych and see if she'll write something.

FG - beside making dampers for ovens, I've been designing and making wood-fired stuff since 1975. Been cooking and heating with wood since '68.