What is "induction cooking"?
Imagine if you could instantly heat food in a pan, without having to wait for the pan to warm up first. Imagine if the heat came not from a flame underneath the pan, but from the pan itself.
The only downside is that it doesn't work with all cookware.
Does it work with cast iron, though? Yes. A resounding yes. Cast iron is a great cookware to use for induction cooking.
You just have to take some precautions, or your cast iron skillet may end up damaging your fancy induction stove.
How Does Induction Cooking Work?
Induction cooking only works on magnetic metal, but it instantly heats the metal without having to first warm up anything under it.
Let's back up to a bigger question: what, exactly, is induction cooking? Time for a brief science lesson.
Both electric and gas stoves work the same way: they have heat underneath the pan (either a hot metal coil or a flame) and then that hot object transfers (or conducts) its heat to the pan. Thus the pan warms up by a process called the conduction of heat. Gas and electric stoves could both be called "conduction stoves."
But this is induction. It uses a cool property of physics: that a changing magnetic field induces an electric current, and then that current causes the metal to heat up. In your induction stove:
1. An inductor (under the glass of the stove) passes an alternating current (AC power).
2. This generates a changing magnetic field.
3. The changing magnetic field induces a current in the metal pot or pan above the glass.
4. The metal pot or pan conducts that current.
5. Because the pan isn't a superconductor, there's resistance.
6. That causes the metal of the pan to heat up.
Upsides
- It's instant
- The coil under the stove doesn't heat up, so you have less risk or burning yourself (the stove will heat up, of course, by conduction from the hot pot or pan above it. But that's not how it's heating your pan).
Downsides
- It only works on magnetic metal
And for the hard-core science nerds
If you really want to nerd out about it, read up on the difference between conduction and induction here. Or nerd out about magnetism here.
Can You Use Cast Iron on an Induction Stove?
Yes. As mentioned, you can and you should.
If you are an avid cook, you may love to cook with old-fashioned cast iron. Cast-iron is one of the healthiest cookware options. It can produce some of the best-tasting food, too.
Do you have a cast iron frying pan? A cast iron skillet? (Those are actually just two different words for the same thing.) If you don't, you should get one.
But then, don't be afraid to mix the old-fashioned and the space-age modern. Cast iron will work great with your brand new induction stove.
Why does it work?
It's metal. It's magnetic. It can carry an electric current.
In case you zoned out during my little science lesson, here's the take-away point: induction cooking only works on metal that's magnetic and can carry an electric current.
Iron is magnetic and can carry an electric current. Ergo, it works on these modern, uber-efficient stoves.
Pros and cons to using cast iron on an induction stove
But is it a good idea to use your old-fashioned cast-iron pan in this way? Let's see:
Pros
- Induction stoves are far more energy-efficient than traditional "conduction" cooking. In induction cooking, 85-90% of the energy goes to heating the food, compared to 65-70% in gas or electric stoves.
- Cast iron is generally more uneven, which means that it won't be touching the stovetop at all points at once. Hence, an electric stove (which transfers heat mostly by contact) is less efficient for cast iron than an induction stove.
- It's faster than cooking with cast-iron on a conduction stove (cast iron takes a long time to heat up).
- Turning off the stove is like turning off the gas. You stop adding heat instantly (though cast iron has high heat retention, so turning it off won't immediately stop cooking your food).
- Induction stoves offer excellent temperature control (again, allowing some time for the temperature to come down, due to the heat retention).
- Cast iron is less prone to sticking.
- Cooking with it may increase your iron intake.
Cons
- As mentioned, cast iron is generally more uneven. This means that it's prone to scratch the glass of your induction stove (and while this isn't a functional problem – unless the glass cracks – it's an aesthetic nuisance).
- Cast iron, with its rustic feel, is also generally fraught with imperfections in the metal. Imperfections mean that the current (which is causing the heating) may be uneven, causing hot pockets and cool spots as it's cooking.
- It's heavy. This makes it trickier to use without scratching or damaging a glass induction stovetop (all induction stovetops are glass).
- It may stain the stovetop glass. This is because cast iron retains bits of food residue more readily than other surfaces (trapped in the micro-crevasses of the uneven surface) so these can burn when it's used, causing stains.
- You don't want to slide the skillet around on the glass; you have to pick it up to shake it as it sears or move things with kitchenware as it cooks.
- It's heavy.
Tips to Avoid Scratching your Induction Stove
First of all, know that induction stoves are normally made with ceramic glass, which is harder than regular glass. In fact, it's harder than cast iron. This means that your cast iron pan is unlikely to scratch it.
However, there are some precautions you can take:
Tip #1: Lift, don't slide
A lot of potential damage would only occur if the uneven bottom of the heavy cast iron pan. So lift. Don't slide.
Tip #2: Wash it. A lot
Cast iron tends to hold food residue that can burn and damage the integrity of your stovetop, even scratching it eventually. Wash the skillet often to avoid this.
Tip #3: Sand the bottom
I'll cover this in more detail later, but you can sand your cast-iron skillet to reduce the unevenness on the bottom.
Tip #4: Use parchment paper
This is probably overkill, but you can place a sheet of parchment paper between the pan and the glass, avoiding any direct contact whatsoever (with the way that inductive cooking works, unless you're heating up the pan a LOT, the paper won't be burnt).
This article has people trying a range of objects between their skillet and the glass stovetop. Apparently parchment paper isn't always safe at meat-searing temperature.
Tip #5: Use induction to heat the pan, then transfer it off the stove
Advice from a carnivore (in the same article as above): "If you can't find a stove-top solution, the workaround is to use the oven to heat the skillet, then remove from the oven and sear while the skillet is resting on a hot pad. The cast iron will hold a significant amount of heat. This will only work for smaller amounts of meat, of course, not 4-pound steaks."
Will cast iron scratch the glass on my glass-top stove?
If used correctly, no. The glass on most induction stovetops is strong, and there are reports of people who've used them for years without a problem.
Just be smart with how you use it.
How to Properly Use Cast Iron on an Induction Cooktop
The main thing is to lift, don't slide.
Cast iron is heavy. You probably don't want to lift it. But that's essential. Please, don't slide your cast-iron pan over your glass-top stove.
Also, wash it frequently.
If there are any stains on the skillet itself, you may want to read up on how to clean burn spots on a cast iron pan.
Can You Use Enameled Cast Iron on an Induction Stove?
Yes. Because you're inducing a current with a magnetic field, that magnetic field can go right through the enamel layer and heat up the iron inside.
Better to avoid scratching
In fact, it may be preferable to use enameled cast iron, because the enameled layer will prevent the rough iron from scraping against your stovetop.
But watch out...
However, enameled cast iron is as heavy as cast iron, and you should still be careful with it, so you don't crack your stovetop glass.
Best Cookware for Induction Cooking
Believe it or not, the best cookware for induction cooking is actually cast iron. Particularly, enameled cast iron, to reduce the risk of scratching your cooktop.
There are, however, other options, which I will outline below.
List of Cookware You can Use on Induction Stoves
Let's start with what NOT to use:
Don't use:
- Earthenware cookery
- Glass
- Copper or aluminum that doesn't have a magnetic surface on the bottom
Instead, go for one of these:
Use:
- Cast iron
- Enameled cast iron
- Stainless steel (most types)
Stainless steel is the trickiest, because it's made with a variety of metals. A high nickel content, for example will actually block its ability to induct current. If you're buying stainless steel, look at the box to see if it's induction compatible.
Best Cast Iron Cookware Brand
There's a clear frontrunner when it comes to picking a brand for your cast iron cookware, and that's Lodge. Over 100 years old, this brand is tried and true. Additionally, they offer a wide range of products: from plain cast iron to pre-seasoned and enameled, and from tiny pans to big baking trays.
Of course, there are other brands who make cast iron cookware. But are they better? You can read this review of Lodge versus other brands, but it basically says this: Lodge products, and those that are sold for up to eight times as much, are essentially the same.
According to reviewers, Lodge is affordable. So don't invest in Fiskars, when it's really no different in quality from what you can buy for fraction of the price.
(I don't work for Lodge or get money from them, I promise. This is just my own finding after doing my research!)
Frequently Asked Questions
In case you're still wondering...
Will Cast Iron Scratch My Induction Cooktop?
Not if used properly. Read above for more on this.
How to Know if your Cookware is Induction Compatible
Hold a fridge magnet to it. If the magnet sticks, the pot or pan should be magnetic enough that your stove can induce a current in it.
If the magnet won't stick, then no. Not magnetic = no current = no heat. Sorry.
Is Cast Iron Magnetic?
Yes. Iron (whatever the type) is magnetic. That's why it works on induction stoves.
How to Make the Bottom of My Cast Iron Pan Smoother
You can actually sand the bottom of your cast iron skillet to make it smoother. Use 40 to 60 grit sandpaper and sand in a circular motion. Oil it well.
You should also season both the inside and outside of your cast iron pans when seasoning them.
So can I use cast iron on a glass-top induction stove?
Yes.
Not only can you, but you should (as long as you can heft the weight of it).
Cast iron is one of the superior cooking materials out there. It cooks nicely, retains heat very well, and it'll give your meal a more cooked feel than stainless steel.
And it works particularly well with induction cooking. The main downside to cast iron is that it takes forever to heat up... but with an induction stove, that's not a problem!
Just be careful as you set it down and pick it up, and don't slide it along the glass, and your stovetop won't know the difference.
Jane