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What Happens When You Pour Hot Liquid into a Glass?

What Happens When You Pour Hot Liquid into a Glass?

How Bad Is It?

Is it bad to pour hot liquid into a glass? According to John C. Mauro, Ph.D., a professor of materials science and engineering at The Pennsylvania State University, unless a glass is specifically made to withstand hot beverages, an effect known as thermal shock could cause it to break. While the inside of the glass expands due to the higher temperature, the exterior stays at room temperature, creating fracture-inducing stress.

Iced CoffeeSo if you’re preparing iced coffee or tea, know that starting with a cold glass full of ice cubes can create thermal shock. Dr. Mauro says that while the trick of putting a metal spoon into the glass will conduct some of the heat away from the liquid, it won’t necessarily prevent shattering. Double-walled containers and borosilicate glass are typically safe for hot liquids, but always check the packaging to be sure.

comment_2What’s your favorite type of cookware? We’d love to know! Please share with our readers in the comments below.


Have you ever broken a glass when you poured hot liquid into it?

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Tanya Aoyagi
Tanya Aoyagi(@spokanegreenclean)
3 years ago

We LOVE our cast iron skillets–they are such a great, eco-friendly way to cook, plus you get the benefit of a little extra iron added to your foods. 😀 We are hoping to replace our old non-stick cookware with a good-quality stainless steel or ceramic set this year (once we get done arguing about which is better…LOL!).

Lynn Babcock
Lynn Babcock(@environan)
3 years ago

I love my Corningware. I can use it in the microwave, on the stovetop and in my full sized oven. It goes from being used to cook right to the table.

Melissa Folsom
Melissa Folsom(@mfolsom)
3 years ago

We have replaced all of our nonstick cookware with cast iron. We search antique stores for the old stuff as it is much smoother and therefore less prone to sticking then the new cast iron. We also have some great stainless steel cookware and old anodized Calphalon which is great.

3 years ago
Reply to  Melissa Folsom

Love the idea of searching the antique stores for the older cast iron! Thanks for sharing, Melissa.

Amanda McKelvy
Amanda McKelvy(@legacysafehavens)
3 years ago
Reply to  Melissa Folsom

Great idea looking at antique stores! I wouldn’t have thought of that.

Sandra Morrow
Sandra Morrow(@sandra-simplyclean)
3 years ago

We are working towards all stainless or cast iron. I want some enameled cast iron!

Kim Metzger
Kim Metzger(@kimetzger)
3 years ago

I use Visionsware, cast iron, aluminum, and one ceramic pan. I worry about getting too much copper from copper pans.

Diane Rudy
Diane Rudy(@dianerudy)
3 years ago

We love using Cast Iron and also use Princess House Stainless Steel Cookware and a few of their PFOA Free Non-stick pieces of cookware (but I’m still concerned that Non-Stick cookware of any type is probably not good).

Amanda McKelvy
Amanda McKelvy(@legacysafehavens)
3 years ago

I LOVE my Pyrex containers! They don’t make them like they used to anymore, but they are still great quality and withstand almost anything.

Heather Wiese
Heather Wiese(@heather)
3 years ago

Arrrrgh! I still have non-stick cookware (frying pans, only) and I do have some cast iron and the rest is stainless steel. I’m am working on getting rid of the non-stick cookware>

Lori Babbage
Lori Babbage(@laabw)
1 year ago

We use The Heritage Rock and Canadian made Paderno pots and pans at our home and cottage.