Urgent: Can I safely bake in Pyrex Mixing Bowl?

Needing a bowl-shaped container for the timballo di riso from Guiulano Bugialli's cookbook for tonight, I realize that I gave my casserole of that shape away.
Though there is a ton of unused batterie de cuisine in the basement, none of the right shape. And my springform has sprung a leak. I'm reluctant to use a straight-sided pan, for fear the unmolding of the rice crust will not go well and will undo the point of this presentation.

Can I safely bake in my 1950's era Pyrex mixing bowl? It is pristine with no cracks or deep scratches. Otherwise, I need to buy something today.

Thanks in advance.

seems to me you could. The internet says all pyrex glasware is safe to four hundred degrees. do not put on direct flame or under broiler. but the sources on the intenet are not really authoritative so who really knows.

Thanks, toria. Would be a baking situation. Maybe I'd bake at a bit lower than the recommended 400 degrees.

The olde-fashioned Pyrex is considered to be safer than the contemporary version. There was a discussion a while back on Pyrex safety, but I can't find it, sorry.

I'd hazard it, were it my choice.

Geo

I own some pieces of vintage Pyrex. Does it say anywhere on it whether it is heat resistant or not? That is usually a good indication of whether it can withstand an oven or a stove top.

I think Pyrex is a formulation not just a brand name. So if the piece is glass and has a pyrex trademark, it should be safe to 400 degrees. The old pyrex is better than the new stuff which in my opinion seems brittle and not the same in feel as the old. There is a bunch of stuff on the internet on old vs new pyrex and people seek out the vintage versions.

I rountinely shop at estate sales and I always see vintage Pyrex galore and sometimes they can be pricey because they are so sought out by people who do not like or trust the newer versions.

Vintage Pyrex was not only a trademark, it was a patented formula for a type of borosilicate glass. What I say next is personal opinion from working several years at Corning Glass as a troubleshooter in their corporate engineering department (M&E Division) in the '80s.

Pyrex that was made in Corning's US glass plants is safe to temperatures higher than 400F. It's the same glass formulation as laboratory Pyrex which can withstand temperatures to 650F, but home Pyrex with added coloring compounds can only withstand temperatures to around 550F. There should be no issue whatsoever with putting a vintage Pyrex piece on the middle rack of a pre-heated 450-475F oven. I say should because old pieces are more likely to have microscopic cracks which limit the top temperature to less than 475F, and probably well under 400F. If you have used a piece of vintage Pyrex in an oven in the recent past, then it will be safe to 450-475F. If not, then use in an oven at your own risk. (No cooktop or broiler...ever!)

Newer Pyrex retains the trademarked name but not the patented formula of borosilicate glass. It is now made from soda-lime glass, and I personally would NEVER use it in an oven.

I've done only the tiniest amount of checking on line but does anyone know what the year cut-off is on the stuff that is "vintage" or original formula versus "new"?

thanks!!

boudreaulicious wrote:I've done only the tiniest amount of checking on line but does anyone know what the year cut-off is on the stuff that is "vintage" or original formula versus "new"?

thanks!!

In my personal opinion, anything up until the 1970s. I have seen things from even the early 1980s considered vintage. But I honestly do not know how accurate that description is or if that is just personal opinion from others.

Mostly trying to determine at what point they changed the formula--not so much what is considered "vintage" for collecting purposes which is what I mainly found when researching on line.

Look at the piece or its packaging. If it's made in the USA, consider it "Vintage" because it was made from borosilicate glass and not soda-lime glass. Corning closed its Pyrex hot-glass plants in New York, Virginia, and Oklahoma in the early and mid-'90s, so that would be the cut-off date.

I am 100% positive that the Pyrex being made in the '80s was borosilicate glass. I used to travel to these plants and would watch it being made, so I feel quite safe in my assertion.

[quote]Look at the piece or its packaging. If it's made in the USA, consider it "Vintage" because it was made from borosilicate glass and not soda-lime glass. Corning closed its Pyrex hot-glass plants in New York, Virginia, and Oklahoma in the early and mid-'90s, so that would be the cut-off date.

I am [i][b]100%[/b][/i] positive that the Pyrex being made in the '80s was borosilicate glass. I used to travel to these plants and would watch it being made, so I feel quite safe in my assertion. [/quote]

Perfect---thanks!

Wow Mark, how can they market pyrex now to be safe in the oven if you say it never should be put in. What about the microwave?

I wrote:I personally would NEVER use it in an oven.

That is my personal opinion. What others do with this information is up to them, and I am not telling them, nor even suggesting to them, what to do.

As for a microwave, do the standard test: put the piece in for 30 seconds on HIGH. If it gets warm/hot, don't use it in the microwave!

[quote][quote="I"]I personally would [i]NEVER[/i] use it in an oven.[/quote]
That is my personal opinion. What others do with this information is up to them, and I am not telling them, nor even suggesting to them, what to do.

As for a microwave, do the standard test: put the piece in for 30 seconds on HIGH. If it gets warm/hot, don't use it in the microwave![/quote]

[url]http://americanceramicsociety.org/bulletin/2012_pdf_files/sept_12/#/40/[/url]

Well the scientific community certainly agrees with you on NOT using the new pyrex in the oven or on the stove top.

I guess we can or rather should say unequivocally - "[size=150][b][i]One cannot safely bake in pyrex manufactured after 1993[/i][/b][/size]"

When in doubt, go to the source. And I strenuously dispute the characterization of newer Pyrex bakeware being unsafe. I'm sure that the Corning corporation, owner of the Pyrex brand/process for both kitchenware and lab-quality glassware, would, too.

Depends on your source. Try this instead: http://www.snopes.com/food/warnings/pyrex.asp

Corning no longer owns or produces Pyrex. They sold the rights and are licensing Pyrex to a company called World Kitchen.

World Kitchen has a vested interest in telling you their product is safe. Snopes is well-known for debunking urban myths. Per (and other sources) the formula for Pyrex was changed from borosilicate glass to soda lime glass. (Snopes says undetermined.) Same label, but a different formula = different results.

Per Snopes, the best one can say for the new Pyrex is mixed results. Consumer Reports has also reported cases of exploding Pyrex ware. http://www.consumerreports.org/cro/magazine-archive/2011/january/home-garden/glass-cookware/glass-cookware/index.htm

sundevilpeg wrote:When in doubt, go to the source. And I strenuously dispute the characterization of newer Pyrex bakeware being unsafe. I'm sure that the Corning corporation, owner of the Pyrex brand/process for both kitchenware and lab-quality glassware, would, too.

The silliness of referencing marketing for objective information aside this topic is of real and significant safety concern. I don't believe the OP was soliciting manufacturers claims or misinformed consumers opinions.

As Mark H and others have pretty fully explained and as was completely laid out in the scientific article I linked to http://americanceramicsociety.org/bulletin/2012_pdf_files/sept_12/#/40/ there is little doubt that soda lime silicate glass has thermal expansion rates that result in fracturing or a statistically significant risk of fracturing during "normal" cooking.

I will readily admit to using my post 93' Pyrex many times for cooking but the evidence in this case is conclusive that Pyrex should not be recommended for use in the oven. Remember, it is not just that new glass cook wear will break - it may violently shatter and cause serious injury.

Was gone for a while and just noticed this topic.

viewtopic.php?p=400286#p400286

Please keep the above in mind. Having said this, I feel compelled to reply to the following:

sundevilpeg wrote:When in doubt, go to the source. And I strenuously dispute the characterization of newer Pyrex bakeware being unsafe. I'm sure that the Corning corporation, owner of the Pyrex brand/process for both kitchenware and lab-quality glassware, would, too.

Can I assume you believe that Lean Finely Textured Beef is just fine for consumption because its primary manufacturer, Beef Products Inc, has stated this in its marketing? If not, why not? Can I assume you believe that genetically-modified seeds, and products such as Roundup, are completely safe because their manufacturer, Monsanto, has stated this in its marketing? If not, why not?

Note that I'm not taking sides here...I'm only trying to find out where you draw the line on believing marketing copy.

I'm a marketing guy, and I believe everything I write. Except this.

--

Congrats on a great new interpretetion of the Liar's Paradox! Well done!

Geo

& ThirdCoastFoodie: kindly try to knock off the personal insults, or at least refrain from unrelated off-topic comments about Monsanto and pink slime to bolster your arguments. Also, I routinely refer to Snopes.com myself, but I would scarcely call that cite a concrete and unqualified reason to give away all of your Pyrex.

All I was trying to accomplish by linking the Corning/Pyrex site was to establish the maximum cooking temperature and any other precautions one should use in using Pyrex bakeware. I note that the thrill-seekers at America's Test Kitchen routinely recommend Pyrex, specifically the 9" by 13" shallow casseroles and 9" pie dishes, and I highly doubt that Chris Kimball is on the Pyrex payroll.

Dial it down a notch, and loosen your tinfoil hats, OK?

I fail to see where I have made any insults. I also fail to see where I have made a single recommendation to anyone else, even going to the point of quoting myself on several occasions. Yet another time:

[quote][quote="I"]I personally would [i]NEVER[/i] use it in an oven.[/quote]That is my personal opinion. What others do with this information is up to them, and I am not telling them, nor even suggesting to them, what to do.[/quote]
I'll even tell you where I stand with the two questions I asked. I personally will not consume LFTB, but that is a personal choice. Much like with current Pyrex, I do not have access to sufficient information to suggest that others do the same. I have no issues whatsoever with the use of genetically-modified seeds or Roundup. In all three cases, I couldn't care less what the companies said about their product; my decisions were made based on personal research. I have stronger opinions about this topic due to my experience working in the factories where "vintage" Pyrex was made. (BTW, what's your experience with Pyrex which led to your statement about tinfoil hats?)

We are having this discussion because you referenced the Pyrex website as "proof" of the product's safety. I am trying to determine your level of research in order to better continue this discussion. So, if possible, I would appreciate your answering my questions.