Did you know there is an actual difference between Pyrex and Pyrex?

Answered by Andrew Fritz

There is indeed a difference between Pyrex and pyrex. The distinction lies in the material used to make the containers and the intended usage.

Pyrex, spelled with an uppercase “P,” refers to a specific brand of cookware that is made of borosilicate glass. Borosilicate glass is a type of glass that is known for its ability to withstand high temperatures without shattering. This makes Pyrex cookware suitable for use in ovens and microwaves. When you see the PYREX label on a cookware item, you can be confident that it is designed to be heated and can withstand the thermal shock that can occur when transferring it from a hot oven to a cool surface.

On the other hand, pyrex, spelled with a lowercase “p,” refers to a generic term for glass containers that are not made of borosilicate glass. These containers are typically made of -lime glass, which is less resistant to thermal shock. As a result, pyrex containers should not be heated in the oven or microwave, as they may break or shatter when exposed to high temperatures.

The difference between Pyrex and pyrex can be quite significant when it comes to their performance and durability in the kitchen. Borosilicate glass, used in Pyrex cookware, is more resistant to thermal stress, making it a safer and more reliable option for heating and cooking. Soda-lime glass, used in generic pyrex containers, is more prone to breakage when exposed to rapid temperature changes.

I have personally experienced the difference between Pyrex and pyrex in my own kitchen. A few years ago, I accidentally used a pyrex container in the oven, thinking it was made of borosilicate glass like my other Pyrex cookware. Unfortunately, the pyrex container shattered into pieces due to the rapid temperature change. It was a lesson learned, and since then, I have been more cautious about using only genuine Pyrex cookware for heating and cooking purposes.

To summarize the difference between Pyrex and pyrex:

Pyrex (uppercase) refers to a specific brand of cookware made of borosilicate glass that can be safely heated in the oven or microwave.

Pyrex (lowercase) is a generic term for glass containers that are not made of borosilicate glass and should not be heated in the oven or microwave.

It is important to pay attention to the distinction between Pyrex and pyrex to ensure the safe and proper use of glass containers in the kitchen. Using genuine Pyrex cookware made of borosilicate glass will provide you with a reliable and durable option for heating and cooking, while generic pyrex containers made of soda-lime glass should be reserved for non-heating purposes.