PYREX vs pyrex: What's the difference and why it matters?

[TheBlackAdder]

Glass cookware from the PYREX and pyrex names is indeed different, and one may or may not be made with borosilicate glass rather than soda lime. But what you think you know about PYREX might not be true. In this video, chef and food writer Matt Degen clears up the confusion.

Old school PYREX is now made in France and still contains the costlier borosilicate glass making it more expensive.

New pyrex does not contain borosilicate, and is instead made out of soda lime glass which is cheaper.

What's the difference -- thermal shock, the ability to tolerate extreme changes in temperature.


UPDATE: But the mystery continues as the upper and lowercase spelling does not definitively identify which glass the products are made from. Even Corning cannot answer that. A mineral oil test can help identify they type of glass, but that is not definitive either. The best advice from the chef is the lowercase pyrex is not borosilicate. If you are in Europe, it's all borosilicate. There are other brands that use borosilicate. If you find PYREX in the US with Made in France... it's probably borosilicate. The chef prefers vintage Corningware, made from pyroceram with properties that even PYREX cannot meet.

[hlthe2b]

1. I knew some of this before, but this is a well-done summary of the facts...

And while my main use is the two-cup measuring cup, I like his suggestion to go with the old vintage corningware casserole dishes that you can find very cheaply at just about any yard sale.

[justaprogressive]

2. The greedy Americans made the product worse

my measuring cups are from the 80's

[Kali]

3. meh I use them all

anybody remember the clear smokey glass cookware from the 70s or 80s that was stovetop safe? my mom had a couple pieces. I didn't really like it but never used it much. was that a corning product?

love the old blue cornflower corning ware and I have at least a half dozen pyrex measuring cups, stacks of bakeware new and old. it's glass, be careful with it. it can break.

[surrealAmerican]

5. It might be what Corning called "visions" cookware.

I still have a small saucepan from the '80s from that line that I use all the time.

[Kali]

6. that does sound familiar

and apparently still being made and sold! https://visionscookingware.com/

[Retrograde]

7. I used my 50-year old blue flower Corning ware

dish to make dinner tonight - goes from stovetop to oven with no problem

My problem with the new pyrex measuring cups is the design- they dribble when pouring liquid

[elleng]

4. SAD, some years ago for, Rosh Hashonah, was baking brisket as had done previously,

and suddenly heard loud 'crash!' Dinner was ruined!!!

I do have 'blue corn flower' pieces somewhere.

[TheBlackAdder]

9. My sister says the new pyrex can't take heat above 500 degrees. She's had them break in the oven.

[Old Crank]

8. I'm in Europe

I got one of the half liter glass Pyrex cups. It is marked in liters and, like the one pictured, in English pints which are 20 ounces. The reverse side has weight markings for flour and sugar. I use a scale personally.

I'm currently building up a collection of LeCreuset. I was gifted one of their Tart tatine dishes. Will have to try one with pear this winter.

The Corning visions. A friend was working for a company that was giving away 10 or 12 ounce little pans. I ended up with a case. I found them great for individual left over servings or vegetables in the microwave.

[Buzz cook]

10. My only problem

Was the red ink washing off a measuring cup.
We have had one glass casserole break in the oven but don't know if it was PYREX or pyrex or some other brand.