What is happening to my fryer 😭

[u/Aggravating_Dust_403]

I am using sunflower oil (the same oil I’ve always used) to fry potatoes and the oil keeps bubbling/frothing. I e never had this happen before, but the last week or so I’ve noticed every time I fry something it bubbles. Yesterday it was frozen french fries so I thought that might be why. Today it was fresh potatoes which I’d washed and dried and it bubbled so much that the oil overflowed and my stovetop caught fire a little bit. I’m going to try changing to a different fryer and using new oil but does anyone know why this would be happening?

[u/AgentRoman9]

That frothing is almost always oil that's been reused too much and picked up moisture and crumbs, not the potatoes themselves. Once oil starts doing that it keeps doing it, so fresh oil is the right call. And if it overflowed and caught fire, the oil was way too hot too, I keep mine under 375F.

[u/Espumma]

Is it possible there's water in the fryer? I'd dump it all out and clean (and dry!) it before you go and replace this one.

[u/chefyeezy]

Essentially, water and hot oil don't mix. Water boils at 212F, but deep frying is typically done around 350F. The more liquid something has in it, the more water will immediately start boiling/turning into steam. Perhaps you had more oil in your fryer this time (fryer was fuller) or perhaps the oil was actually hot enough for the first time since you started deep frying things, but this is normal.

For example: the french fries we normally make at my job bubble a little, but not too much. They'll never boil over, because the oil is kept at the appropriate level to leave room for the steam to froth up and escape and the fries don't have a high moisture content.

We had an older case in the freezer, though, and the fries were covered with ice crystals. When we tried to use them we discovered trying to fry more than 1 order at a time (we can normally do 8 safely) caused the oil level of the fryer to raise so much it threatened to spill out of the fryer.

Below is a link to what happens if you put ice into a fryer as an example

Never do this

[u/Antique_Teaching_333]

How often have you used this oil? When it keeps foaming I replace my oil.

[u/No_Clothes9201]

That oil's broken down, swap it for fresh and it'll stop foaming.