What about the inevitable heat loss?

[Puy de Dome]

If a joint of meat would ordinarily require, for example, two hours roasting at 170 degrees C (the actual temperature doesn't matter), how do you maintain this temperature if there is no fire in the wfo?

With an electric or gas oven you can obviously set the temperature on the dial, and as if by magic the oven keep, more or less, that temperature.

What's the trick with a wfo, then?

Put the meat in at the given temperature and let it cool as it must? Or start at a much higher temeprature and potect the food from burning?

P de D

[Frances]

Re: What about the inevitable heat loss?

Put the meat in at a slightly higher temperature and remove it at a lower one - so the heat on average is about what you'd use on a regular oven. More or less.

This works, because a WFO is far more forgiving than a regular one, the food won't burn as easily (although sometimes covering can be a good idea). It gets easier the more you get to know your oven, and how it cools down.

For example, mine falls from 260 to 200 C fairly quickly, so I know I have to get bread in there fast the moment the temperature is low enough. (This is for large amounts of bread though, it wouldn't be a big issue for one or two loaves). But then the oven seems to hang around 180, 170 C for ages, so there's a longer time window for things like roasts. Your oven may cool differently, you'll just have to try it out.

You don't need to add extra heat (say with another fire), because the bricks have absorbed heat from the initial fire throughout their thickness. They will continue to slowly release this heat into the oven chamber for days until they reach ambient temperature.

Hope this helps

[Puy de Dome]

Re: What about the inevitable heat loss?

Thanks Frances.

I'll have a go at the joints next time doing your suggestion of starting off higher than normal. But of course allowing for the drop in temperature, which, as you say, will vary from oven to oven.



P de D

[dmun]

Re: What about the inevitable heat loss?

The old cookbooks suggested putting a roast in a very hot oven, and then turning down the heat after a while. This mirrored the experience of solid-fuel cooks who naturally worked with declining temperature curves. It works great.

[Puy de Dome]

Re: What about the inevitable heat loss?

So my near-panic (exaggerating a little for effect) at the thought ofthe oven cooling too much is unfounded? My reaction has been, on these three occasions where I have had big fires, to leave the coals in there with the roasts. I know that's really only for pizza cooking, but felt compelled to keep a small fire going.

I don't have any reason to believe that I lose lots of heat via the floor. Wish I had been around more yesterday to properly monitor the heat loss; as it was family life demanded my attention elsewhere.

Slightly off-topic, is there a preference on the Forum to use farenheit over celcius in these discussions?

Many thanks

P de D

[Frances]

Re: What about the inevitable heat loss?

Oh celcius, definitely!!
Nah, seriously the concensus seems to be use whatever you're most comfortable with.

Don't tell anyone, but I nearly always leave the coals in after pizza (because I'm lazy) but they soon go out once the door is in place. By the time the oven is ready for roasting there's no significant heat coming from the coals.

I'm sure you'll have plenty of opportunities to observe your oven's heat loss. What temperature was this morning?

[Puy de Dome]

Re: What about the inevitable heat loss?

Temp this morning was 90 celcius.

I put a couple of potatoes in silver foil in there about four hours ago - just checked them, and they are partially cooked, I think. We're not in a hurry, so will leave them another four hours and see what has happened to them. Maybe they'll have cooked, maybe not.

Temp yesterday got to around 300 celcius, I think, but I didn't cook at that temp - we did roast chicken once it got down to about 170, which, while the chicken cooked nicely, was perhaps a bit low to start with, and the potatoes were a bit under-done.

P de D

[Puy de Dome]

Re: What about the inevitable heat loss?

Oh, that's the other thing... I am measuring the heat on the floor of the oven, and sometimes the walls and the ceiling - is this a good measure of the cooking heat?

I do have some free-standing thermometers. But the main way I have is with the infrared. Don't we, ideally, want to know the temperature somewhere in the middle space of the oven - somewhere in mid-air?

P de D

[DrakeRemoray]

Re: What about the inevitable heat loss?

I usually measure the temp in the dome and then the air is about 25-50 deg F lower...

So if I have a 425 dome, I probably have a 375-400 degree oven...

Drake