Does glass bakeware need to be seasoned?

I’ve been baking my own bread recently. I have two old glass breadpans: one hand me down, one resale. The baked bread just falls out of them, zero resistance.

My sister bought me a third, new, so I would bake some for her too.

So I just pulled all three out of the oven. The two old ones released the bread smoothly and immediately. The new one, the bread is like baked in, like epoxy. Absoutely impossible to remove in one piece.

Is it the age that makes a difference? I mean, I wouldn’t think so because glass is inert, right?

Any help on this?

Checking to make sure this isn’t GQ. Ok, I’m going to speculate.

First, I’m pretty sure glass is not inert in the sense of unchanging, but it is largely unreactive to chemicals. I don’t know why. I’m also surprised that any glass baking dish would ever release baked goods without butter or oil or something.

My second thought is that it’s possible that the formula for glass bakeware has changed, or that different companies have different formulas (you didn’t say if the new pan was the same brand as the old ones).

Thirdly, this sounds like a great question for the folks at America’s Test Kitchen who deal with cookware. But it might take a while to get an answer, so in the meantime, I’d butter and flour it or line it with parchment paper.

Yes of course I know the workarounds. I’m just trying to figure out what’s going on

Are the old ones Pyrex(Borosylicate glass) as opposed to pyrex or Anchor Hocking( soda lime glass)?

Pyrex as opposed to pyrex?

The recipe for Pyrex has changed. As usual the old stuff was great and the new stuff is crap (and could shatter).

Does the new formula have different thermal expansion/contraction? That could explain the release, if the glass “squeezes” out the contents ever so slightly.

Another difference between old and new glassware is wear … scratches etched into the surface.

Although, I would guess a scratched up surface would be less likely to release, not more, so that can’t possibly be the issue here. So, uh, scratch that last part.

Thank you! This has to be it.

New one is Pyrex, but so is one of the old ones. The other oldie just has a W on the bottom.

I’d also wonder about heat transfer rate. One cake could be more or less baked on the bottom, which would affect how it sticks.

It’s likely the W stands for Westinghouse

Turns out OXO uses borosilicate. Might have to buy one of those, use the new Pyrex for things that DO need a greased pan, like quickbreads and casseroles.

It was supposed to say PYREX vs pyrex, but I missed the fact my browser cleaned it up. They changed to lower case name for the new stuff.

Could be years of seasoning, despite the instinct that glass doesn’t need it or accept it. I know glass cleans up well, but after years of use, some of my glass bakeware appears to have a subtle film on the surface. The subtle film is maybe significant?

I’ve never tried baking bread in glass, incidentally. Is there a significant advantage over metal, do you find?