# How dangerous would it be to use a pressure cooker as a deep fryer? **URL:** \ **Category:** Factual Questions\ **Created:** [August 11, 2014, 1:51am UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280 "2014-08-11T01:51:19Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Artemis\_Tardis](https://avatars.discourse-cdn.com/v4/letter/a/4bbf92/32.png) [@Artemis\_Tardis](https://boards.straightdope.com/u/Artemis_Tardis)\ **Post date:** [August 11, 2014, 1:51am UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/1 "2014-08-11T01:51:19Z")
Let’s say that you are in a hurry. You have to cook 100 kg of pork rinds and you don’t have so much time. You look at your kitchen and see your good’old pressure cooker. You fill it up with a few cups of oil, add the pork rinds, close the lid and put it on the stove. What happens next? Perfect fast pork rinds? Big Cablam? ---
**Author:** ![running\_coach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/running_coach/32/15836_2.png) [@running\_coach](https://boards.straightdope.com/u/running_coach)\ **Post date:** [August 11, 2014, 1:55am UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/2 "2014-08-11T01:55:35Z")
100 kg? As in 220 lbs? Wow. ---
**Author:** ![running\_coach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/running_coach/32/15836_2.png) [@running\_coach](https://boards.straightdope.com/u/running_coach)\ **Post date:** [August 11, 2014, 1:59am UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/3 "2014-08-11T01:59:54Z")
[This thread at eGullet](http://forums.egullet.org/topic/139932-deep-frying-in-a-pressure-cooker/) mentions that a pressure cooker is not a pressure fryer. From a quick look through, this is _ **not** _ something to try. ---
**Author:** ![lisiate](https://avatars.discourse-cdn.com/v4/letter/l/f05b48/32.png) [@lisiate](https://boards.straightdope.com/u/lisiate)\ **Post date:** [August 11, 2014, 2:03am UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/4 "2014-08-11T02:03:15Z")
Can a domestic stove get hot enough to boil the oil at all? This suggests [soybean oil](http://van.physics.illinois.edu/qa/listing.php?id=1428)boils at around 300 degrees C. A gas stove could reach that temperature, but I’m not sure about electric stoves. ---
**Author:** ![Artemis\_Tardis](https://avatars.discourse-cdn.com/v4/letter/a/4bbf92/32.png) [@Artemis\_Tardis](https://boards.straightdope.com/u/Artemis_Tardis)\ **Post date:** [August 11, 2014, 2:05am UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/5 "2014-08-11T02:05:53Z")
I am pretty sure I have been cooking my food at lower temperatures… Like 170 C. ---
**Author:** ![Enola\_Straight](https://avatars.discourse-cdn.com/v4/letter/e/dec6dc/32.png) [@Enola\_Straight](https://boards.straightdope.com/u/Enola_Straight)\ **Post date:** [August 11, 2014, 2:06am UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/6 "2014-08-11T02:06:49Z")
IIRC, Col. Harlan Sanders used pressure cookers full of oil instead of water back in the 50s and 60s when he first started up Kentucky Fried Chicken. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [August 11, 2014, 2:07am UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/7 "2014-08-11T02:07:50Z")
> [@lisiate](#): > > Can a domestic stove get hot enough to boil the oil at all? This suggests [soybean oil](http://van.physics.illinois.edu/qa/listing.php?id=1428)boils at around 300 degrees C. A gas stove could reach that temperature, but I’m not sure about electric stoves. Electric stoves can melt aluminum, so, yes. ---
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [August 11, 2014, 2:11am UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/8 "2014-08-11T02:11:57Z")
> [@running\_coach](#): > > [This thread at eGullet](http://forums.egullet.org/topic/139932-deep-frying-in-a-pressure-cooker/) mentions that a pressure cooker is not a pressure fryer. > > From a quick look through, this is _ **not** _ something to try. From that thread > [@](#): > > You can only “pressure fry” in an industrial pressure fryer. This should not be attempted in a “pressure cooker” because they, and their rubber/silicone parts and valves, are not designed to manage the extra high temperatures of oil under pressure. Most pressure cooker manuals recommend against it and in addition to the danger you put yourself in by being scalded, there is a true risk of explosion of super-heated oil that could then catch fire and put your home in danger. > > Do not even try pressure frying in your pressure cooker. > > Sorry. > > Industrial Pressure Fryers look like this. Fagor makes (or made) a stove-top version, but it is named and marketed as a “pressure fryer” and not a “pressure cooker” and not to be confused with a “pressure fry pan” which is basically a low, wide pressure cooker shaped like a fry pan but is not a pressure fryer, either. ---
**Author:** ![running\_coach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/running_coach/32/15836_2.png) [@running\_coach](https://boards.straightdope.com/u/running_coach)\ **Post date:** [August 11, 2014, 2:12am UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/9 "2014-08-11T02:12:25Z")
> [@Enola\_Straight](#): > > IIRC, Col. Harlan Sanders used pressure cookers full of oil instead of water back in the 50s and 60s when he first started up Kentucky Fried Chicken. [Here’s an article](http://www.slate.com/articles/business/when_big_businesses_were_small/2013/10/kfc_origins_a_roadside_diner_became_a_global_phenomenon_thanks_to_a_little.html) about it. It was rather dangerous and Sanders had to train new franchisees on how to do it. > [@](#): > > Filling the pressure cooker with hot oil rather than water only ups the danger factor. Today’s fast-food chains use specially designed pressure fryers to ensure safety, but Sanders seems to have simply encouraged his clients to live dangerously. > > Presumably, Sanders was not the only person to try putting oil in a pressure cooker sometime in the 1940s. But he did help popularize it—alongside original franchisee Pete Harman, who developed training manuals and product guides for franchisees that led to safer large-scale pressure frying. ---
**Author:** ![Artemis\_Tardis](https://avatars.discourse-cdn.com/v4/letter/a/4bbf92/32.png) [@Artemis\_Tardis](https://boards.straightdope.com/u/Artemis_Tardis)\ **Post date:** [August 11, 2014, 2:17am UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/10 "2014-08-11T02:17:57Z")
I would love to see the results of this disaster. Mythbusters! ---
**Author:** ![usedtobe](https://avatars.discourse-cdn.com/v4/letter/u/ec9cab/32.png) [@usedtobe](https://boards.straightdope.com/u/usedtobe)\ **Post date:** [August 11, 2014, 7:43am UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/11 "2014-08-11T07:43:20Z")
Sneak a peak at the machines at a KFC - those are massive chunks of steel with serious clamp-down covers. Home pressure cookers operate at 6 psi - with water, that is somewhere around 156F. Heating oil to 6psi gets you some serious temps. In the early 70’s, a whole bunch or people put a clamp on the top of their pressure cookers and called them “Pressure Fryers”. Disasters ensued. Never put more than 2 Tablespoons of oil in a pressure cooker. I looked this stuff up ten - 15 years ago. Sorry, no cites - but I’m sure the info is still out there. ---
**Author:** ![Ignotus](https://avatars.discourse-cdn.com/v4/letter/i/ecc23a/32.png) [@Ignotus](https://boards.straightdope.com/u/Ignotus)\ **Post date:** [August 11, 2014, 12:00pm UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/12 "2014-08-11T12:00:42Z")
Why on earth would you want to deep-fry anything, besides your worst enemy, _at 300 C?_ It would make the surface a charred mess, while the inner parts were still raw! I do a fair bit of cooking for myself, and I still have some scars on my hand and forearm to remind me to _never, ever put a solid lid on a deep-frying pot_. The reason: water vapor will condense on the inside of the lid, and as soon as you touch it to remove it, drops of water will fall into the oil, with, in hindsight, predictable results. Nowadays, I use the kind of lid made of a mesh of thin wire - it allows the water vapor to escape, while still, mostly, preventing oil splattering. 180 C is pretty much optimal for deep-frying, and is easily obtained with an open pot on an electric stove. Doubling the recipe doesn’t call for a doubling of temperature! ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [August 11, 2014, 12:09pm UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/13 "2014-08-11T12:09:05Z")
Cooking pork rinds involves driving off moisture from them - I don’t think a pressure cooker vent will be sufficient to allow it to escape - if significant moisture stays in the system, that’s going to continue to boil and create pressure after the pan is removed from the heat source - by the time this has finished (i.e when the oil has cooled to below the boiling point of water), the pork rinds will be ruined. Alternatively, attempting to remove the lid while there is still superheated water in the system seems almost guaranteed to end very badly. ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [August 11, 2014, 12:55pm UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/14 "2014-08-11T12:55:13Z")
> [@usedtobe](#): > > Sneak a peak at the machines at a KFC - those are massive chunks of steel with serious clamp-down covers. > > Home pressure cookers operate at 6 psi - with water, that is somewhere around 156F. > Heating oil to 6psi gets you some serious temps. Confirmed. I worked at a KFC restaurant for a short time in the early 1990s. As an aside, the kitchen of a KFC restaurant is the greasiest location in the universe. Anyway, they used an open-air fryer for the extra-crispy recipe, but the original-recipe chicken was fried under pressure. They actually had two fryers. One was a little fryer used for small batches: you lowered the trays of chicken in by hand and closed/opened the pressure lid by hand. The other fryer was a monstrous industrial machine with enough rack space to fry 20 “heads” (one “head” = the parts from a single bird) and was much more automated. At the start, the lid of the pressure chamber (maybe 3’ x 2’) was up, and you loaded the trays of breaded chicken onto arms that hung down from it. When ready, you pushed a button, and it lowered the lid/chicken into a vat of hot oil, and sealed the lid against the tub. I don’t recall the pressure they used, but it couldn’t have been much; 3’x2’ works out to 864 square inches, so (for example) a pressure of just 3 psi would have required a clamping force of 2600 pounds. I think the intent was not to allow the oil to get hotter, but to prevent the water in the chicken from turning to steam quite so rapidly, keeping the outer layers and breading moist long enough to cook the inner layers completely. To answer the OP’s question: using a home pressure cooker as a pressurized deep fryer is not a good idea. When a PC is filled with water, the temperature is controlled by the pressure relief valve: the water boils at a temperature that is determined by the pressure set via that valve, and so the cooker _will not_ get hotter than that, no matter what you set the burner to. If your pressure cooker is filled with oil instead, the oil can be heated to ludicrous temperatures - not particularly because of the pressure, but because you won’t have a thermometer in it and so you’ll have absolutely no idea what temperature it’s at. Heating large volumes of oil to its boiling point (which is what will probably happen) is a Very Bad Idea. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [August 11, 2014, 1:05pm UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/15 "2014-08-11T13:05:53Z")
> [@Machine\_Elf](#): > > If your pressure cooker is filled with oil instead, the oil can be heated to ludicrous temperatures - not particularly because of the pressure, but because you won’t have a thermometer in it and so you’ll have absolutely no idea what temperature it’s at. Heating large volumes of oil to its boiling point (which is what will probably happen) is a Very Bad Idea. Unless, as **Artemis\_Tardis** says, you’re Mythbusters. I’d love to see them tackle this one - but it’s probably too obscure. ---
**Author:** ![Malacandra](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@Malacandra](https://boards.straightdope.com/u/Malacandra)\ **Post date:** [August 11, 2014, 2:17pm UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/16 "2014-08-11T14:17:22Z")
> [@usedtobe](#): > > Sneak a peak at the machines at a KFC - those are massive chunks of steel with serious clamp-down covers. > > Home pressure cookers operate at 6 psi - with water, that is somewhere around 156F. Celsius, surely? 156 F isn’t even boiling point. ---
**Author:** ![Bozuit](https://avatars.discourse-cdn.com/v4/letter/b/edb3f5/32.png) [@Bozuit](https://boards.straightdope.com/u/Bozuit)\ **Post date:** [August 11, 2014, 5:11pm UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/17 "2014-08-11T17:11:57Z")
Water boils at around 170 degrees F at 6 psi. But 6 psi is considerably less than atmospheric pressure, so a pressure cooker is unlikely to be using it. According to Wikipedia, pressure cookers reach temperatures of more like 250 F. ---
**Author:** ![running\_coach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/running_coach/32/15836_2.png) [@running\_coach](https://boards.straightdope.com/u/running_coach)\ **Post date:** [August 11, 2014, 5:15pm UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/18 "2014-08-11T17:15:59Z")
> [@Bozuit](#): > > Water boils at around 170 degrees F at 6 psi. But 6 psi is considerably less than atmospheric pressure, so a pressure cooker is unlikely to be using it. According to Wikipedia, pressure cookers reach temperatures of more like 250 F. That’s 6 psi over atmospheric. ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [August 11, 2014, 5:29pm UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/19 "2014-08-11T17:29:59Z")
> [@running\_coach](#): > > That’s 6 psi over atmospheric. AKA 6 [psig (not 6 psia).](http://en.wikipedia.org/wiki/Gauge_pressure#Absolute.2C_gauge_and_differential_pressures_-_zero_reference) ---
**Author:** ![Bozuit](https://avatars.discourse-cdn.com/v4/letter/b/edb3f5/32.png) [@Bozuit](https://boards.straightdope.com/u/Bozuit)\ **Post date:** [August 11, 2014, 6:41pm UTC](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280/20 "2014-08-11T18:41:38Z")
> [@running\_coach](#): > > That’s 6 psi over atmospheric. _What_ is 6 psi over atmospheric? Certainly not the pressure at which water will boil at around 170 degrees Fahrenheit. [Next page](https://boards.straightdope.com/t/how-dangerous-would-it-be-to-use-a-pressure-cooker-as-a-deep-fryer/695280.md?page=2)