Cracked oven proof dish - trying to understand the physics of what went wrong
I was baking bread for the first time in years the other day, and the instructions said put a baking tray full of water in the bottom of the oven. I didn't have a metal baking tray, so I put a ceramic ovenproof dish in the oven, and let it warm up. Then I boiled a kettle and poured it into the dish. DISASTER! The dish cracked immediately, spilling water into the bottom of the oven.
Obviously this was a dumb mistake. Next time I'll use a deep metal baking tray etc.
However, I'm trying to understand why this happened, because when I make a stupid mistake I like to fully understand what went wrong. I wouldn't have thought the temperature differential between the ceramic dish and the boiling water was sufficient to cause the sort of rapid expansion that would cause this to happen.
Any insights?
Best Answer
You have answered your own question, it was the rapid change in temperature which caused the ceramic to crack. Oven temperature for bread baking is usually somewhere around 200°C/400°F, whereas water is 100°C/212°F, which is not a trivial difference. Everyone thinks boiling water is hot, but it's cool compared to a hot oven. Rapid changes of temperature aren't ideal for glass or ceramic.
That isn't to say that your ceramic dish should have shattered, but it isn't a surprise. Next time feel free to use a ceramic dish but put the water in it at the outset, although they aren't ideal. I prefer to use a wide metal baking tray instead because it has a lot of surface area for water to evaporate, baking dishes won't get your oven moist as quickly.
Pictures about "Cracked oven proof dish - trying to understand the physics of what went wrong"
Why did my ceramic dish crack in the oven?
Crazed CeramicFine cracking on the surface of a ceramic dish's glaze is known as "crazing." If you have a new dish that you know was made with safe glazes, you can continue to use it. Some older dishes contain trace amounts of lead and other heavy metals, however. These can leach into food through the crazed surface.Can you use cracked ceramic dish?
Cracks in any dishes hold bacteria so they are always unsafe. Never use dishes with any cracks in them for food.Can you fix a cracked casserole dish?
A ceramic baking dish can be glued in certain conditions. It's mostly ok to use commercial grade super glue, but only if the 2 ceramic pieces do not have any cracks. So, if you have a broken dish that needs to be fixed, glue is your only choice.How do you keep a glass baking dish from cracking?
It's best to put the dish on a dry dish towel or a metal cooling rack to cool. Damp towels or surfaces can also cause the hot glass to shatter. Don't use tempered-glass bakeware on the stovetop, under the broiler, in a toaster oven, or on a grill.Teen Titans Go! | Fooooooooood! | DC Kids
More answers regarding cracked oven proof dish - trying to understand the physics of what went wrong
Answer 2
Presumably the dish was pre-heated to bread baking temperature (?450F?) but the water was at least 200F cooler. Water has a HUGE heat of vaporization. It takes 5.4 times as much heat to convert water to steam as it does to bring the same water from 32F to 212F. All that heat is sucked out of the surface of the baking dish , cooling it to 212F.
Ceramics have poor heat conductance. Poor conductance means the water side of the dish cools down, but the other side doesn't. The cold side shrinks, but not the hot side. This produces a huge stress inside the ceramic material.
Ceramics have low elasticity. This means the material can't bend (like steel) so the stress can't be relieved by warping.
Ceramics also have poor tensile strength. They break when stretched.
Glass breaks in tension. It is incredibly strong in compression. "Heat proof" glassware is tempered. The tempering process puts the interior of the material in tension and the surface in compression. The compressed surface closes cracks which could start a break. But the stresses between surface and interior store a lot of energy. So when it goes, it explodes
That's why the dish shattered: Big temperature difference, big tensile stress. POP !
Sources: Stack Exchange - This article follows the attribution requirements of Stack Exchange and is licensed under CC BY-SA 3.0.
Images: RODNAE Productions, Andrea Piacquadio, RODNAE Productions, Gagan Cambow