The algorithm fed me this just yesterday. Fascinating! And shame on Pyrex! (or is it PYREX?). Lucky French!
*edit*
For the record, I'm American and I have PYREX measuring cups with all-caps, also clearly displaying that they're made in the USA (presumably within the last 30 years). Mimicking Ann, I don't believe you can rely on all-caps being Borosilicate. Gotta try that veggi-oil trick.
I concur. Not sure if that would be enough to tell. Best to see what it's actually made from. If one has a dish and really can't find out what it's made from that oil trick was good. Pretty neat and just the interesting fact that Ann would find out.
Ann probably mentioned this but if they're still using the name Pyrex then people will still think it's exactly the same as a pyrex product. This she definitely mentioned. Pyrex is synonymous for products that can stand baking. To change this and still call it pyrex is dangerous.
It's surprising to me that none of the companies that have owned the Pyrex brand in the US have clearly addressed the question in the decades this has been studied and under discussion. A spokesperson took it up with wikipedia editors here and said that the Charlesroi, PA, plant has been making Pyrex with tempered soda-lime since the 1940s, but really they should just spell it all out (all plants, all brand owners in all countries, all logos, specific dates) because this issue keeps getting rediscovered every few years and that can't be good brand management.
I think they should tell the pros and cons of each, and put clear labels on their products so that consumers can make their own, informed, decisions.
Pyrex with borosilicate
Pyrex with tempered soda-lime
Cost
More expensive
Less expensive
Environmental impact
Uses more energy to manufacture
Glass recycling centers cannot burn hot enough to remelt/recycle it
Uses less energy to manufacture
Some glass recycling centers can burn hot enough to remelt/recycle it
Sudden temperature changes
Best: Can withstand sudden temperature change of up to 330° change (F)
Can withstand sudden temperature change of up to 100° change (F)
Impact-resistant
Can withstand some impact
Best for withstanding impacts from drops, knocks, and falls
I worked in chemical manufacturing for ≈30 years and preferred borosilicate glassware, but mainly for its superior chemical resistance over tempered soda-lime glass. Thermal resistance was a lesser consideration as I would never subject lab glassware to the extreme shock that is depicted in the video. I can also attest to the fact that borosilicate glass is easily broken or cracked by fairly light impact. I always visually inspected my glassware for defects (especially "star" cracks) before use, especially if it was to be heated.
I found technical specifications for Duran borosilicate lab glass that states the maximum differential temperature, ΔT < 100 K (°C). Duran is the trademark for Schott's borosilicate glass. (Corning's Pyrex is a similar borosilicate glass developed in the USA. Corning still makes Pyrex borosilicate labware.)
The Wirecutter article describes a test from the Cookware Manufacturers Association's CMA Engineering Standards for Cookware and Bakeware manual that is much less extreme than the one conducted in the video. It describes abrading the glassware with sandpaper, heating in an oven for 20 min, and submerging in water bath with a ΔT = 220 °F (≈104 °C); note that this is the same ΔT as that recommended by DWK for Duran glassware. The video heats the glassware at 220 °C (428 °F) and submerges it in cold water. The water temperature is not specified, but ΔT ≈ 200 °C (392 °F)!
Incidentally, the Chapter 11 bankruptcy mentioned in the video is mostly because of debt and weakness in InstantPot sales.
The algorithm fed me this just yesterday. Fascinating! And shame on Pyrex! (or is it PYREX?). Lucky French!
*edit*
For the record, I'm American and I have PYREX measuring cups with all-caps, also clearly displaying that they're made in the USA (presumably within the last 30 years). Mimicking Ann, I don't believe you can rely on all-caps being Borosilicate. Gotta try that veggi-oil trick.
I concur. Not sure if that would be enough to tell. Best to see what it's actually made from. If one has a dish and really can't find out what it's made from that oil trick was good. Pretty neat and just the interesting fact that Ann would find out.
For the excellent videos she makes. Very well done, lot's of dedication and informative.
I'm a firm believer if it ain't broke then don't fix it. Why did Pyrex have to change a good formula?
The brand "Pyrex" was bought by another company, and it was the latter that decided to change the type of glass, according to what I have read..
Ann probably mentioned this but if they're still using the name Pyrex then people will still think it's exactly the same as a pyrex product. This she definitely mentioned. Pyrex is synonymous for products that can stand baking. To change this and still call it pyrex is dangerous.
It's surprising to me that none of the companies that have owned the Pyrex brand in the US have clearly addressed the question in the decades this has been studied and under discussion. A spokesperson took it up with wikipedia editors here and said that the Charlesroi, PA, plant has been making Pyrex with tempered soda-lime since the 1940s, but really they should just spell it all out (all plants, all brand owners in all countries, all logos, specific dates) because this issue keeps getting rediscovered every few years and that can't be good brand management.
I think they should tell the pros and cons of each, and put clear labels on their products so that consumers can make their own, informed, decisions.
Pyrex with borosilicate
Pyrex with tempered soda-lime
Cost
More expensive
Less expensive
Environmental impact
Uses more energy to manufacture
Glass recycling centers cannot burn hot enough to remelt/recycle it
Uses less energy to manufacture
Some glass recycling centers can burn hot enough to remelt/recycle it
Sudden temperature changes
Best: Can withstand sudden temperature change of up to 330° change (F)
Can withstand sudden temperature change of up to 100° change (F)
Impact-resistant
Can withstand some impact
Best for withstanding impacts from drops, knocks, and falls
Made in
France
U.S. (and China during the pandemic)
I worked in chemical manufacturing for ≈30 years and preferred borosilicate glassware, but mainly for its superior chemical resistance over tempered soda-lime glass. Thermal resistance was a lesser consideration as I would never subject lab glassware to the extreme shock that is depicted in the video. I can also attest to the fact that borosilicate glass is easily broken or cracked by fairly light impact. I always visually inspected my glassware for defects (especially "star" cracks) before use, especially if it was to be heated.
I found technical specifications for Duran borosilicate lab glass that states the maximum differential temperature, ΔT < 100 K (°C). Duran is the trademark for Schott's borosilicate glass. (Corning's Pyrex is a similar borosilicate glass developed in the USA. Corning still makes Pyrex borosilicate labware.)
DWK DURAN Laboratory glassware catalogue EN.pdf excerpts:
Note the warning not to place hot glassware on a cold or wet lab bench is similar to the tempered glass bakeware warnings.
Here are articles that provide more info on the pros and cons of tempered soda-lime glass vs borosilicate glass:
https://web.archive.org/web/20141120095647/http://stats.org/stories/2009/exploding_pyrex_oct14_09.html
https://www.nytimes.com/wirecutter/blog/tempered-vs-borosilicate-glass/
The Wirecutter article describes a test from the Cookware Manufacturers Association's CMA Engineering Standards for Cookware and Bakeware manual that is much less extreme than the one conducted in the video. It describes abrading the glassware with sandpaper, heating in an oven for 20 min, and submerging in water bath with a ΔT = 220 °F (≈104 °C); note that this is the same ΔT as that recommended by DWK for Duran glassware. The video heats the glassware at 220 °C (428 °F) and submerges it in cold water. The water temperature is not specified, but ΔT ≈ 200 °C (392 °F)!
Incidentally, the Chapter 11 bankruptcy mentioned in the video is mostly because of debt and weakness in InstantPot sales.