Baking time difference in pyrex versus metal

Question

What baking time is optimal for recipes that are done in pyrex for banana bread versus metal baking dish?

Answer 1

Time is only a rough indication of whether any dish is "done", the biggest 'unknown factor' from your question is, "what temp are you baking at?".

I would suggest you use the following 3 tests to determine when your banana bread is done (regardless of whether you are using pyrex or metal):

1. The bread is very brown and solid on top
2. A toothpick or chopstick inserted into the bread comes out completely dry. (Even a few moist crumbs are evidence that your bread is not done.)
3. The bread has reached an internal temperature of 195°F to 205°F (90°C-95°C)

Each condition should be met in order, so don't bother with the toothpick until you see the rich brown color, then once the toothpick is clean, check the internal temp.

Answer 2

Everything Cos Callis indicates about times being approximate, and how to test if the banana bread is done is true.

However, there is a general pattern of the difference between glass an metal baking pans that is direct consequence to how ovens cook the food. Baked goods will typically cook somewhat faster in the glass pan, than in metal.

There are two ways to compensate for this:

• Some people lower the temperature by about 25 F to make the time come out more evenly.
• The other options is to watch the item closely to see when it is done, which may be somewhat earlier than in a metal pan.

Since what is most often baked in glassware are quick breads and savory dishes, neither of which are terribly sensitive, it really isn't something that needs to be worried about deeply.

It is a far larger factor with cookies, but they are almost never cooked on glass. Still, you can see the same effect because cookies bake faster on dark cookie sheets than light colored ones.

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The reason that items cook faster (at a given temperature) in glass is that the major mode of heat transmission in an oven is infrared radiation, which is a form of light (with a wavelength too long to see, so it is invisible). This is the same reason holding your hand near an old style incandescent light bulb without touching it would still feel warm.

Glass pans are transparent to infrared, so all of the radiant heat is pretty well applied to the food. Metal pans are more reflective, so some reflects off. The darker the pan, the more they absorb, and the more quickly the food cooks.

This is not to say that convection and conduction to not also cook the food, but they are a lesser factor.