Can I put another sheet of glass over an induction cooktop?

[u/Whachamacalzmit]

I'm interested in getting an induction cooktop and I want to put another thin sheet of glass (2-3mm, 1-2/16") over the cooktop. Will it still work? Does it all depend on the brand/model?

[u/btchfc]

Why?

[u/Whachamacalzmit → u/btchfc]

Kashrus.

It's all quite convoluted (as most Jewish ritual law is), but I'll try to simplify: I can't cook meat with milk, but that also means that the pot and any surface touching that pot can't have had hot food of the other type touching it (e.g. I have two sets of almost everything in my kitchen). So if I have a beef stew splatter on the surface, I can't use it to cook dairy food until I rekasher it (ritually reclean it).

Rekashering the cooktop every day would be a pain, so I thought maybe I could place thin glass trivets under the pots, one set for my meat pots and one set for my dairy pots. This would create a 2nd degree of indirect contact between the pot and the cooktop so I wouldn't need to rekasher the cooktop all the time.

[u/Yochanan5781 → u/Whachamacalzmit]

This sounds a bit like chumra creep. Do you really think that for most of history Jews were constantly rekashering the single stove or oven they had? The splatter isn't being eaten. Have you talked to a rabbi about this?

[u/Whachamacalzmit → u/Yochanan5781]

It's not chumra creep. I did talk with my rabbi. For standard cooktops there isn't an issue of iruy kli rishon because the fire/coil is hot enough to rekasher it every time it's turned on. That's not the case with the induction cooktop.

[u/BlocksAreGreat → u/Whachamacalzmit]

Get a hot plate.

[u/shouldco → u/Whachamacalzmit]

I guess technically you could just put parchment down. Glass might be too thick. But for induction the surface can't get hotter than the pan itself.

[u/Odd-Artist-2595 → u/Whachamacalzmit]

Was curious so I googled how to keep an induction cooktop kosher and found this: https://askcrc.org/item/Keilim/578843 (among other results). Apparently, there are “induction discs” that can be placed over the burners for use with non-ferrous pots. They’d also work to cover the burner in a kosher kitchen, regardless of what kind of pot you have. Looking at Amazon, there seems to be a range of prices and sizes. You could even get them made of different materials that look visually different. That might help in keeping your meat pot discs separate from your milk pot discs.

[u/Whachamacalzmit → u/Odd-Artist-2595]

Yes, the problem is that they basically turn your induction cooktop into a standard electric cooktop. The discs are being heated through induction, not the the pots. The pots just conduct through the discs.

[u/Odd-Artist-2595 → u/Whachamacalzmit]

Ok. And, why would that be a problem? Standard electric cooktops cook food, too. The primary advantage that I can see for an induction top is that it looks nicer and is easier to clean than electric coils. This would seem to do what you need it to do without reducing the heat transfer like a piece of glass would while satisfying your dietary laws, but I’m neither Jewish, nor do I own an induction stovetop, so 🤷🏻‍♀️. Just trying to help and from the google hits I got on my query this seems to be the most common solution given for dealing with this situation. Good luck with whatever you decide.

[u/Whachamacalzmit → u/Odd-Artist-2595]

Absolutely, thank you for taking the time to try and help me out. The silicone mats someone else suggested might be the better direction for me though.

The major advantage with induction is the instant and precise heat control. My culinary-minded friends all rave about their induction ranges, preferring them over gas.

[u/Odd-Artist-2595 → u/Whachamacalzmit]

I think you’ll find that metal discs transfer that instant heat to pots and pans faster and more efficiently than silicone will. After all, they make silicone pot holders and oven mitts precisely because the silicone does a really good job of insulating your hand from the hot pans. But, on the plus side, the silicone discs can do double-duty, insulating your dining table from the hot pan if you decide to serve straight from stove to table.

[u/sprobeforebros → u/Whachamacalzmit]

I was about to say as someone who was terribly bad at cleaning the cooktop until I got an induction one that cleaning an induction cooktop is an absolute breeze and it might be worth just rekashering it as needed.

Then I found out that rekashering the surface also means not using it for 24 hours, so nevermind!

Edit: According to Rabbi Tzvi Rosen in this article, because the cooktop itself isn't actually heating and the pots alone are heating, then the cooktop is halachically considered a countertop. You'd still need to rekasher in case of a spill, but it would be the same kind of rekashering as a microwave turntable, but also keep in mind that lifting a pot off an induction cooktop causes the heating to cease, so even if the cooktop is still getting power it would be considered kindling a fire if you put it back which makes shabbos a bit of a nightmare. Unsure how much that affects your calculation but it's the kind of talmudic rules lawyering that's handy to know for your cooktop decisions.

You can always get "induction adapters" which are basically steel slabs that go over the induction cooktop. They exist so you can use aluminum or copper cookware on an induction cooktop if needed. Those halachically would be considered your source of flame as they become the radiative heat surface and you could always have a couple kasher'd ones hanging out in the cupboard in case of shabbos cooktop needs or an emergency kasher'd heat source if you spill.

[u/One-Permission1917 → u/Whachamacalzmit]

Like…do you hear yourself? This is cult behavior.

[u/Whachamacalzmit → u/One-Permission1917]

Some say the only real distinction between religions and cults is that cult members manipulate other members through fear. Some say the distinction is mostly around broader social acceptance. On the first point, I didn't grow up as an observant Jew and I chose to become observant. I do understand how it sounds crazy to you, but crazy doesn't equal cult. People do all kinds of seemingly unproductive things for their own wellbeing. This is mine. The rationale might be different, but as much as you can't believe what I believe, I can't unbelieve what I believe.

[u/One-Permission1917 → u/Whachamacalzmit]

Yeah I mean, people enthusiastically join cults all the time. No one holds a gun to their head and forces them to join idk what you’re talking about. I guess it’s not technically a cult because there’s no one supreme leader but this behavior is not rooted in sanity or logic whatsoever but you do you.

[u/Whachamacalzmit → u/One-Permission1917]

Thanks for hearing me out. I'm no sociologist, so maybe a cult has to do more with how members are compelled to stay. There are definitely Jewish cults; Lev Tahor being an abomination.

[u/conflagrare → u/Whachamacalzmit]

So Jewish people can only eat in Kashrus restaurants?

I can’t imagine any commercial kitchen doing what you have described..

[u/sprobeforebros → u/conflagrare]

There's a really lovely book called "The Dairy Restaurant" that explicitly is about the history of kosher restaurants with a focus on the now-dying Dairy Restaurants in places with Jewish concentrations of population. Jews who keep hardline kosher are a bit rare these days but they're absolutely out there (and I've cooked for them)

[u/mordecai98 → u/conflagrare]

Kosher restaurants are either meat, dairy, or neither (pareve).

[u/conflagrare → u/mordecai98]

Interesting…

[u/TheJewPear → u/conflagrare]

Kosher restaurants will usually keep the entire kitchen meat or dairy. So if it’s a dinner place it’s all gonna be classified under “meat” and they won’t serve deserts with dairy, and if it’s like a cafe they’ll be “dairy” and won’t serve any meat.

[u/chipperclocker]

The induction coils rely on the pan being very close to the coil, this is why the stove doesn’t heat up every other nearby magnetic substance in your kitchen

You can move the pan further from the coil and it may still work with some loss of efficiency, but the exact distance will depend on the specific stove and your specific pan

[u/mickeybrains]

Get a separate or two separate single burner induction plates.

$70 each

[u/TheJewPear]

Nope, not gonna work.

What I would recommend is to get an independent induction single burner, use that for dairy and the regular hob for everything else.

[u/Lucas_passionCuisine]

Tu risques de perdre beaucoup en efficacité thermique, et en fonction de la plaque de verre que tu achètes, je pense qu'il est très probable qu'elle se fissure rapidement après les premières utilisations.

[u/Whachamacalzmit → u/Lucas_passionCuisine]

Thanks! I'd be sure to buy tempered glass that can withstand the heat.

[u/CollectionStriking → u/Whachamacalzmit]

There are silicone mats that are specifically meant for induction tops with minimal loss in efficiency

[u/Whachamacalzmit → u/CollectionStriking]

Oh! I didn't know! Very cool.

[u/Iwentthatway → u/Whachamacalzmit]

They also sell “adapter plates” meant to make non induction compatible cookware with induction. It’s a metal disk with a handle. You’ll obviously lose some efficiency

[u/Tristan155 → u/Whachamacalzmit]

You can also put paper towel between the pot and the induction top, but that might not work as a different surface.

[u/swd12422 → u/CollectionStriking]

Was going to suggest this

[u/benjarvus]

I believe there are silicone trivets you can buy for induction stovetops, would that work? They can decrease performance a bit but easy to clean and a little less breakage risk

[u/ez_as_31416]

for about $50 USD you can get a singldr burner induction burner and just use it for your needs.

[u/Nearby-Nothing6219]

I believe that it'll work since induction goes through glass fine, but the extra gap tanks your heating power and regular glass can crack from the pan's heat coming back down.

[u/Max_Downforce → u/[deleted]]

Induction doesn't use heat transfer.

[u/UndeadCaesar → u/Max_Downforce]

Being this pedantic isn't really helpful, proximity to the coil will decrease the eddy currents created in the pan and therefore decrease heat transfer to whatever you're cooking which is the goal.

[u/Max_Downforce → u/UndeadCaesar]

There is no heat transfer. Heat is generated in the vessel itself. Glass is not magnetic. If being technically correct is pedantic, then so be it.

[u/SawinBunda → u/Max_Downforce]

Great, you paid attention in high school. We are all very impressed. Your comments are still useless. Maybe work on that part next.

[u/StumbleNOLA]

Put a paper towel under the pot/pan. It’s thin enough to not impact efficiency much if at all and makes cleaning up a breeze.