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At What Temperature Does Pyrex Self-Destruct? (moved from Home Cooking)

Hi Chow-Chefs!

Rothman dinner plans tonight include chicken thighs, rosemary, whole cloves of garlic, and lotsa chopped onions all sprinkled with truffle oil - and all mixed together nicely and roasted in the oven at as high a temperature as your consensus of advice will allow me to use, without fear of an explosion that would render the chicken inedible by reason of being peppered with multiple shards of glass.

Ladies and gentlemen - your preferred temperature, please!


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  1. It is not so much gthe temperature but the age of the pyrex. It does develop glass fatigue and that can cause the shattering. If it was your grandmother's pyrex i might plant paperwhites in the dish instead of using it in the oven.

    2 Replies
    1. re: Candy

      Old topic, but dangit, I read through this whole thing, put my whole chicken in the oven in my GRANDMOTHER'S pyrex. I read yours last.

      1. re: Candy

        I don't buy the age hypothesis. I regularly use pie plates that are about 40 years old. My mother has a baking dish older than that. The main risk with an old Pyrex dish is that the longer it is around, the greater chance that it will acquire a nick through careless handling. If the dish had a weakness manufactured into it, this would take awhile to manifest itself into a fracture, but that shouldn't take many years.

      2. Pyrex will not self destruct, so don't worry.
        I roast chicken at 425. SOmetimes a higher heat it makes the garlic and onions burn. Make sure the onions are in large chunks.

        1. My local newspaper has an "action line" column. For the last couple of years, exploding pyrex has been a repeat topic.

          This is what I remember from the articles, Pyrex is no longer made by Corning. This happened in the late 90s. Exploding pyrex became common in the late 90s. The exploding pyrex was not damaged. The exploding pyrex was not exposed to extreme temperature changes. I remember 450 as a temperature in the articles. The initial articles tried to blame the user until Mr Action Line did some investigating and found exploding pyrex is somewhat common. And Mr Action Line recommends against using new pyrex.

          I have corning and anchor hocking from the 80s, I don't worry about exploding pyrex, I hope I don't get an unpleasant surprise. I don't use pyrex for dry baking/roasting, only lasagna.

          Do you feel lucky?

          1 Reply
          1. re: Alan408

            It says made in USA but does not specify a maker other than "Pyrex" - will 425 be safe?

            Alan - suddely I feel like Clint Eastwood is holding a gun and I'm holding a Pyrex pan of unknown vintage, and he's calling me a punk!

          2. The biggest thing with Pyrex as far as I can tell (and I have used it in lab settings as well as in a kitchen) is just not to cool it down to quickly - so I would not set it down on a marble countertop or pour cold water on the dish if you take the stuff out. Otherwise it seems to be fairly heat resistant (as long as there are no hairline cracks as Candy mentions).

            1 Reply
            1. re: LauraB

              I think it can withstand a lot of heat, it's the hot to cold that you have to worry about. I had one crack on me one time and that was the reason.

            2. OK, Guys and Gals - I give up! I just transferred the entire project to the bottom of the stove's enamel broiler pan. It's all over. I could not take the risk - because i wanted to roast that chicken at a really high temp and I couldn't afford to risk the double resulting tragedy of losing dinner and then having no pan in which to cook tomorrow's planned dinner - which, being lasagna, is just too much of a coincidence - given all the warnings and the mention of the saving of pyrex FOR lasagna - there must be some divine intervention in there somewhere.
              At least the enamel broiler pan can't explode!

              Thanks anyway, everybody!

              1 Reply
              1. re: niki rothman

                Oh Niki, I don't think you are supposed to put pyrex in at about 450. Good move.

              2. I am sorry you had to abandon your plans - I hope the dish turns out great!

                I use my cast iron pans for the high heat dishes, they do such a service to a cook, the recipe, and are just beautiful!

                19 Replies
                1. re: gotvin

                  Hi gotvin,

                  I appreciate your condolences. I put the chix 'n fixins in the broiler pan right after my last post and I just went in and turned the spuds, which were browning at 450. the chicken looks great, the skin browning and crisp with what looks like all the fat burned away, which was my intention with the combo of high heat and dark meat - hoping for the meat staying moist and the skin getting perfectly crispy.

                  I have a confession for you about our mutually beloved cast iron pan. I think I ruined mine by placing a layer of olive oil in it for storage (honestly, I was relying too much on nonstick and ignoring the cast iron - big mistake, it needs to be used often to stay in good shape) and the oil has turned into a horrible resinous tacky, hard yet sticky in a nasty way, mess. God help me I have no idea how to rehabilitate it.

                  So, I'm thinking about investing in an expensive clad roasting pan for the type of thing I'm doing tonight or when I want to go with the highest heat. The lasagna CAN always go in the pyrex at 350 - no problem. But I'm getting into wanting to roast meats at a high heat in the oven.

                  When I want to do a whole chicken or anything I can tie onto the skewers like a chicken or leg o' lamb I use my compact countertop little electric rotisserie, which is so wonderful - so reliable - everyone should have one (I'm serious), Juicy meat/crispy skin - perfect meat every time. (tip - if you get one just always oil the insertion points)

                  BUT...as of tonight, looks like there's going to be a big "clad" roasting pan in my future too.

                  1. re: niki rothman

                    So sorry about your cast iron- maybe re-seasoning will help? Coat with shortening and put in the oven at 300. Pour off excess oil when it melts, then put back in the oven and bake for another 2 hours.

                    btw- I HAD a pyrex explode on me once, and it's not the temp, it's the rapid cool down.


                    1. re: julietg

                      I did something similar to my first CI back when I didn't know better. A good reseasoning did the trick for me, so I think julietg is probably spot on.

                      1. re: julietg

                        Well, can you solve this problem? The pan is very old and the black carbon coating, better known as the precious patina - got deeply and widely scratched when I first tried to remove the sticky resinous dried on oil I had thought was going to prevent rust when the pan was not being used.

                        So it just looks so ugly and I'm not sure just removing the sticky resin coating is going to do anything at all to deal with the ruin that I have made of the underlying black surface where it is now patchy and back to the original surface in some spots and still beautifully deeply black over about 80 percent of the flat surface.

                        One chowhound here suggested taking it to a pizzeria and asking them to burn it back to the original surface in their super-hot oven, and that is a good idea if you are already on friendly terms with an insider, which I am not - but in any case what would be the difference in doing that and just tossing the once collectible quality 12" pan and going out to buy a nasty new virgin grey cast iron pan and hoping that after about 30 years of daily bacon frying then it MIGHT looks as good as the one I ruined - before I ruined it!

                        1. re: niki rothman

                          DON'T THROW IT OUT!!!!

                          You should be able to save it by re-seasoning. It may take time for it to completely recover, but it will be worth it.

                          Ok, so you don't know any pizza guys. I suggest you make friends with somewhere close over the next few weeks, then ask. Or, if you insist on starting over, send me the pan. I'll take it!

                          1. re: Pylon

                            OK, Pylon - you say I should just take it to the local pizzeria and ask them to leave it in the back of the oven - for how long? Do you have your email address on your "my chow" page in case for some reason the plan fizzles?

                            1. re: niki rothman

                              No no, I said get to know them first, then ask the favor. Time will probably depend on the amount of gunk, oven temp, etc. If you make friends with them, they might be willing to keep an eye on it for you.

                          2. re: niki rothman

                            Pyrex: That temperature should not be a problem if the piece is in good shape - no hairline cracks, etc. Shouldn't put pyrex directly on a burner, cool too rapidly or (I seem to remember from a pyrex booklet) under a broiler.

                            Cast Iron: If the pizza place is not an option, perhaps go outside, set it on bricks upside down & blast it with a little plumbers torch. That should supply enough heat to get rid of the sticky stuff. I have had good luck with the natural citrus cleaners getting rid of baked on sticky messes on pyrex and stainless steel, but would try to burn the mess out first. Good luck!

                        2. re: niki rothman

                          Cast iron can come back from anything. If the reseasoning above doesn't work, stick it into a fire on your grill until it's red hot. The yucky stuff will burn off completely, then you can reseason it like it's the first time. I've also heard of putting it in the self-cleaning cycle of your oven for a similar effect.

                          1. re: JGrey

                            Weeeell...I live in an apartment with no grill (baring carbon monoxide poisoning), and hate to admit my urban low-class status but my oven does not even have a self-clean cycle. Heck, only 3 of the burners even work!
                            Any other ideas?

                            1. re: niki rothman

                              Niki: people are going to scream bloody murder at this... but like you my options were limited. So i put it in the sink overnight in HOT soapy water (gasp), and the next day after work a lot of the "gunk" had dissolved (yes, of course the water got cold..but the initial hot helped begin the process.) Next I heated it under the broiler for about 2 hours (hotter than the hottest setting because the broiler doesn't turn off) and burned the rest. Then I took my old heavy duty useless for cooking metal spatula and scraped off the burnt remains. After all that abuse I was amazed at how much was left of the original seasoning. Not shiny and beautiful, but still a long way from a new pan. After a couple of seasonings and cooking a few batches of bacon (hey... it freezes) it was almost as good as old. (Next time I let someone house-sit, I'm hiding that pan.)

                              1. re: KaimukiMan

                                Your last sentence had me laughing out loud. I've got to ask what in God's name did the house sitter do to that pan? I WILL try your method. What do you think about Easy Off (the no-fumes type)?
                                Bacon - hey, no problem, I LOVE Niman ranch bacon (no chemical preservatives, kindness to animals - and that tastes so good) Soooo...how would you suggest I re-season it if I get the pan back to something that feels hopeful?

                                1. re: niki rothman

                                  I've been afraid to ask, some odd combination of oil and sugar (i'm guessing) that could almost have been used on the bottom of the space shuttle for re-entry. More a case of a friend who needed a break from a roommate than an actual house sitter.

                                  Once you get the surface down to a reasonably smooth finish, (might need some rock salt rubbed around with the bottom of a tuna can-flat bottom), then just rinse really well, light coating of oil and into the hot oven for a couple of hours. I'm pretty sure that the Lodge cookware site has re-seasoning directions.

                                  1. re: KaimukiMan

                                    Thank, Kaimukiman! checking the Lodge site is an excellent idea. And it's niot like somebody here doesn't ask the question about every other day. I'll do a little search. The thing is, it's one of those catastrophes in life you just never figure is going to happen to you...Just kidding, God, if ruining a cast iron pan, no matter how perfect the patina WAS, is the worst thing that ever happens to me, I'd be very, very grareful.

                                2. re: KaimukiMan

                                  Perfect story -- in spite of what internet people may imply -- cast iron is nearly indestructable.

                              2. re: JGrey

                                I work in a pizza place and we have a customer who asked us to "burn off" his cast iron, which was no problem. If you are friendly with your pizza place you can ask them to put it in their oven when they are doing the sicilian pans or the "screens".

                                1. re: Siobhan

                                  Siobhan, this is a great idea! Like Niki, I have an old, no-self-clean-cycle, only-three-burners-work oven. And I have two rusty/gunky cast iron pans. I think my cast iron pans and I are going out for pizza tomorrow!


                              3. re: niki rothman

                                I recently splurged on a beautiful Bourgeat roaster from yourcookware.com. I don't know if it is clad, but it is a sturdy beauty from France that was considerably less than the All Clad model (but by now you know that I always feel smug when I find something I like that is not All Clad :) ) This looks like it can't be killed in a high oven or broiler, and it is deep enough for lasagna! Check it out when you get a chance


                                It's worth comparison shopping at least a little bit.

                              4. re: gotvin

                                I bought a remaindered le creuset roasting pan at a good price, and adore it. The cast iron retains the heat like nothing else, and the enamel coating is really easy to clean. Great for lasagnas, roast chicken,etc. and you don't have to season it!!!

                                I'm feeling a bit anti-pyrex at the moment too. My pyrex mixing bowl chipped with no obvious cause, and I had to chuck away two loaves-worth of prefermented bread dough which was contaminated with the chip of glass. I guess they don't make 'em like they used to!

                              5. I had *NO* idea that I could go any higher than 350 using any pyrex-type pans. I have tons of that crap and never dare to go over 350!! I can't stand cooking in glass & have been thinking of getting rid of all of it anyway. It's heavy (esp the 11x14), ugly and I'm so terrified of exactly what you describe- exploding shards of glass inside my oven- or in my face as I bend to pull it out... Instant nightmare.

                                4 Replies
                                1. re: Boccone Dolce

                                  Hi to all the Pyrex People out there!
                                  I made a wonderful find when I was looking for the proper container to bake Mark Bittman's no-knead bread which requires a 450 degree oven with heating the container and lid for 30 minutes prior to baking. I found a glass loaf/bread pan WITH a lid at a Thrift Store in Portland, Oregon. It is obviously old and I just love it, especially since the price was only $7.00. I guess I just assumed it was Pyrex. I just looked at it and it does not say Pyrex, the only mark is a W that is underlined. It has baked numerous loaves of bread at the high temp and I really love it! Any ideas on what brand it might be?

                                  1. re: salemjan

                                    i thought i was the only one to have a problem with pyrex. my issues were always adding a liquid to a roasting, whatever. ya know, to try and degalze. every time i tried, my glass whould explode.thought it was just me...

                                  2. re: Boccone Dolce

                                    Hold on there! Even I have gone to 400 with pyrex. And I don't think it is ugly at all - could you instead see it as a beautiful thing that it allows you to totally look at the underside of your lasagna or casserole - I always enjoy this "window on the food" view, myself. And the shapes are so classic too - round, square, rectangular - so honest and down to earth. And a great all-American kitchen icon somehow.

                                    Now as to cooking with it, I wasn't complaining about pyrex in my OP, I was just afraid I'd bust something I really do value by cranking the oven up to 450. But, I'll swear to you - glass is not a fast heat conductor but as long as you are doing something like a lasagna, casserole, brownies - where you don't need to sear juices in immediately like you do with meat - well then, there is NOTHING better for baking in the oven than pyrex glass. It holds the heat, cooks very evenly without hot spots. And, as I mentioned, you can easily see if the bottom of your lasagna is getting a bit dark, so you know you need to turn down the heat. These are all important qualities absent in any other material other than really expensive clad pans - and there you still cannot see through them!

                                    1. re: Boccone Dolce

                                      .....or hot shards of glass DOWN YOUR SHIRT as a dish of Shrimp Scampi explodes in your hands.....use me as a cautionary tale: be very careful with this Pyrex at high temps. I've swapped all of mine out for some very nice Le Creuset pans (good excuse to do so!). My scars have healed, but it was a very traumatic experience, indeed.

                                    2. Why not just put your Pyrex dish in the oven empty but wrapped in some foil and crank the oven up to 450 or 500 even for a little extra margin, and see what happens.
                                      Pyrex softens at 1500o F. and is worked at 2300o F. Pyrex is deliberately formulated to be resistant to rapid temperature change, but of course, its resistance can be exceded with a little carelessness. I would think nothing of cranking the oven up to 450o with a Pyrex dish in it, in fact I did just that the other night to brown the skin of a chicken I was roasting.

                                      2 Replies
                                      1. re: LRunkle

                                        Why ask for trouble? The chix turned out delish done in the enamel steel broiler pan - so very good I put the recipe on the home cooking board.

                                        1. re: LRunkle

                                          You're not supposed to bake Pyrex empty.

                                        2. i've roasted a turkey in my calphalon roasting pan at 500, the pan has taken a beating at that temp but it is still just fine and i think i high roast turkey is the way to go. have never had pyrex explode but i would not go above 400 with it, pretty much only use it these days for eggplant parmigiana.

                                          2 Replies
                                          1. re: susan robin

                                            I recently purchased a pyrex baking pan and I was using it for everything. I was making chicken one night with the temperature at 425 and "bang!" it exploded. I could not believe the mess. I could see it just cracking...but exploding into thousands of pieces? I had to take my oven apart to find all the pieces. Lesson learned: I don't use Pyrex at high temperatures any more. (in fact I don't use it at all!)

                                            1. re: sventhegod

                                              That's the way tempered glass breaks. It never just cracks.

                                          2. I've had 2 pyrex explosions. Neither time was extremely high heat. Both times it "exploded" during the process of taking out of oven...holding edges with pot holders, the POW! Glass and food all over the place. Company replaced each piece, but I hardly use the stuff anymore.

                                            1. Pyrex can explode if heated to fast or even the sudden shock of cold air or setting down on a cold counter we don't always relieze the things that can cause thermal shock most think of things like from oven to cold water or such but any sudden change can cause thermal shock i work with Pyrex on a daily basis and even after all these years still sometimes cause 2 inch thick rods to shatter

                                              1. This is one funny topic. It isn't so much the temperature, but the change of temperature. Sudden change of temperature can make many types of glass crack.

                                                1. Fracture of tempered glass is not just a matter of temperature, but of temperature differential. Also defects in the glass, either during manufacture or later.

                                                  A glass baking dish is not a roasting pan. This usage is not advisable.