On Tuesday, 21 January 2020 17:35:13 UTC, newshound wrote:
On 21/01/2020 15:22, Chris Hogg wrote:
On Tue, 21 Jan 2020 03:34:47 -0800 (PST), wrote:


What type of glass is it, borosilicate? Pyro glass can be bought.


https://en.wikipedia.org/wiki/Glass-ceramic#Cooktops

From that link

"If food with a high sugar content (such as jam) spills, it should never
be allowed to dry on the surface, otherwise damage will occur."

It's not immediately obvious to me why that should be. Obviously, if you
cook it on underneath something like a frying pan that you take up to ~
200C you may get something very adherent giving a risk of scratching
when you try to remove it.

But if you let sugar syrup "dry" (or, perhaps, freeze) on the surface
surely it will just dissolve away once cold using a sufficiently wet cloth.

Although I have not done so myself, it wouldn't just be sugar - it would have started to caramelise and then, quite likely, carbonised.

Some jam making people do things like put baking parchment (or similar) underneath the jam pan.

There are many suggestions out there - vinegar, some scrapers, bicarb, etc.

(I was under the impression that if seriously burned on, it will actually react with the glass.)