the physics inside the oven

[Hometechdoc]

Retromom asked about the physics inside the oven. There is so much invloved that you could actually write a book on the topic, but here are the basics.

First, you must understand that there are three primary types of heat transfer - conduction (molecule to molecule), convection (through a medium -air or water) and radiation (intense rays).

All three are present in an oven. Most ovens rely on radiant heat transfer - heat reflected from the walls and other surfaces, which is hard to control and engineer. Convection on the other hand is easier to regulate, but harder to engineer unless the oven was complety circular.

Since most tradiational ovens are relying on radiant heat food close to the walls and ceiling or the bottom rack are exposed to more heat intensity so they brown faster. A smaller oven almost always cooks faster than a larger one even at the same temperature.

I have the 24 inch Miele oven at home and I turn the oven on to cook the 15 pound turkey when the first guest arrives. It usually cooks in one and a quarter to one and a half hour. comparted to two to three in a larger oven.

 

[maytagbear]

Thank you!

This is very interesting.

I have some questions, please:

Could the smaller oven thing be why Stouffer's and the others say to not bake their products in a toaster oven?

Next question: Is electricity really better for flour based cooking? I have heard yes, and I have heard no. I do know from personal experience that electric ovens are dryer than gas ones. I used gas ovens for my first twenty years of cooking....

Thank you so much, not just for answering questions, but for being here!

Lawrence/Maytagbear

 

[scott55405]

Very interesting! I use my toaster oven constantly since normally it's only me. It doesn't seem a lot different in performance from the regular oven, but I'll have to be conscious of it as I use it, to see what I notice.

 

[Hometechdoc]

small ovens

Yes, often toaster ovens and small countertop ovens are not well suited for heating some convenience food items. Usually, the better quality the oven the better temperature regulations, which is the real issue. Not preheating a toaster oven can cause a problem too.

For most oven activities, I prefer an electric oven for two reasons. First the temperature regulation is more accureate (ture only of new ovens) and they are less inclined to heat up the kitchen

 

[scott55405]

I've always preferred electric to gas cooking, and probably always will, but since electric ranges are rare in Los Angeles, I now have gas. I am having a much better experience with it here than I did having it one previous time in Minnesota. The one in Minnesota was very slow on the cooktop, and I'd have a hard time getting the oven to get up to and stay at temperature. This one works better on both counts, and in this instance I have a nice strong overhead exhaust fan that I use to keep room heat from the operating oven in check.

 

[toggleswitch]

I do know from personal experience that electric ovens are d

CH4 +O2 ==> CO2 + H2O (+NOx +SOx, etc)

Methane (natural gas) + oxygen ==> yields
heat + carbon dioxide + water vapor. There are also small amounts of nitrous oxides and sulphuric oxides present upon combustion.

So yes, 100% correct- gas cooking is moister. This also makes gas dryers a bit less harsh, as well, as compared to electric ones.

I have heard that a pan of boiled water in an electric oven help keep things moist.

 

[tomturbomatic]

BUT, Toggle, gas ovens have larger vents and have a draft through them to vent the products of combustion so moisture would be carried away whereas an electric oven with a one or 1.5 inch diameter vent cooks food in more of a closed atmosphere. The electric oven vents excess moisture and expanding air as it is heated without causing foods to lose moisture to a constant flow of air.

 

[lederstiefel1]

I had them all!!!!!

I'm glad to say that I have expierences with so many types of ovens!
Solid fuel - liquid fuel - gas - electricity!

Liquid fuel is seldom used for ovens, more for stoves, except AGA. AGA is a very special type of cooking but it has perfect results!

Solid fuel I like most. There was never ever in my life more juicy meat nor fluffier cakes or more crusty poultry than in a range with wood/coal/turf-burner. The heat is nearly pure radiation from FOUR or FIVE sides directly and one or two further (front and / or rear) in reflected form. The ovens are smaller than with electric ranges and a big turkey has only two to three fingers wide space between the poultry skin and the walls of the oven. Humidity is quite high - like in gas-ovens - and the intense of the radiation heat is deeply going into the goods.
Gas is also nice - enough humidity and a very equal heat as a lot of the heat is circulated hot air from the burner. BUT: because of the very intensive heat from the bottom you should never bake in dark tins! Always use silver ones whereas in a solid-fuel oven silver tins never bake satisfactoringly as they reflect the radiation heat. In electric fan ovens you can use silver ones as well as black ones but in a conventional oven same rules must be abide as in solid-fuel ranges.
Fan-ovens tend to dry out things when they are electrically run - gas fans are not so bad.

Ralf