The Science Behind Pressure Cookers

Dan explains how pressure cookers quickly work to produce delicious results.
Buy our winning pressure cooker: cooks.io/2WuY3OB
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[@enduril122]

Thanks for the explanation. I think besides just cooking at a higher temperature inside the cooker, the pressure itself transfers thermal energy deeply beneath the food surface rather than just being hotter. Frying in oil is hotter at the food surface but will only burn and dry out the food if its too hot. Pressure cooking inhibits the water inside the food itself from evaporating (boiling) out during the cooking process. Instead, the inside and outside are cooked more evenly together which makes everything cook faster without fear of burning. The steam pressure also has the added effect of loosening and tenderizing the food which speeds up the process as well. All this is especially more true for dense, high volume, low surface foods such as large chunks of meat compared to regular cooking

[@jessieyuan1366]

thank you so much for this explanation!! i was studying thermodynamics and searching specifically for this since i didn't understand how a higher boiling point would make cooking faster

[@screamingiraffe]

2 years late, really like this reply, nice work. Also known as 'what's it like to stand on Venus'

[@janepoultney5207]

Yes, I was hoping they'd do this. Lots of people don't understand pressure cookers that well, including me.

[@u235u235u235]

he didn't actually explain HOW the pressure cooker keep the meat moist LOL vs lower boiling temp fail on video

[@lindabeard7035]

I have been using a pressure cooker for 50+ years, as my Mother did before me. I've never had a bad cut of meat come out of it yet. I have a new one pot cooker but can't seem to leave my trusty pressure cooker just yet . Maybe one day. Have been watching America's Test Kitchen for at least 20+ years and I learn something new all the time (and here I thought I knew everything...lol).

[@ollie9777]

hard to even find an old school pressure cooker in VA now days.

[@sylviahacker6695]

I love my pressure cooker, especially in the summer. Less heat buildup in the kitchen plus it's fast.

[@zuzanahoudkova4497]

works great. i love that it has stainless steal pot inside kzbin.infoUgkxG-7WiT7ocumjytOpHDFt632PL0pxXRAg and not the one with coating. we used to have a coated pot before, and the coating slowly peels, and i am sure went into the food that we cooked. Absolutely love stainless steel, and will not use a coated product again.This pot has many settings and many buttons, and i need to sit down with a manual to figure out which setting to use. I used the basic functions, and even though i am not technologically skilled, i turned it on and assembled it without any help.Very satisfied with this product overall.

[@wotan10950]

I bought a pressure cooker last year on ATK’s recommendation. Very pleased with the results. I haven’t tried pot roast yet, but I’ve successfully made hummus, chicken soup, and (for my dogs) bone broth and chicken feet collagen.

[@GeneralKenobi69420]

Can I be your dog?

[@dadoscriticos]

Every kitchen has one of those here in Brazil. Thanks for the clear explanation!

[@sidd9248]

​1:46 oops. Didn't see that coming😂

[@ammaribrahim5756]

I like this guy

[@kevinaptowicz8354]

I'm a Dan Souza super fan. Love your stuff Dan. Keep up the excellent work.

[@hollym5873]

Love being educated. Thanks

[@fakethiss]

I always click when I see Dan

[@harveyh3696]

René Tailleur I always click when I see ATK.

[@2klatte]

Please do a vid comparing stovetop pressure cooker vs the instantpot

[@madthumbs1564]

Helen Rennie (youtube) already has a great video on that.

[@fabulous1610]

Must have in the kitchen. Very Good product. Check here: amzn.to/2t647Dm

[@mb7hl]

This one is easy. Stove top pressure cookers, especially the ones with a weighted rocker, are designed to work at 15psi/259°F/120°C. Virtually at recipes are based on this. The average pressure/temperature in any electric pressure cooker is no more than 12psi/242°F/117°C This may not seem like much of a difference, but because the ideal maillard reaction only happens at 15psi, while food may come out ok, it's never perfect.

[@seikibrian8641]

@@mb7hl "The average pressure/temperature in any electric pressure cooker is no more than 12psi/142°F/117°C" I think you meant 242°F, not 142°F.

[@mb7hl]

@@seikibrian8641 corrected

[@DramaisFunny]

This posted right when i was going to pressure cook for the first time

[@seikibrian8641]

How did things turn out?

[@DramaisFunny]

@@seikibrian8641 Been pretty successful. Figuring out the right amount of fluid needed is probably the largest learning curve.

[@Bramble20322]

@@DramaisFunny You should always prefer more liquid than less. One of the risks of pressure cookers is explosion due to the water boiling out and the pot overheating. You can boil of the water after you're done cooking to reduce it anyway if you put too much. Put too little and you may need a new kitchen.

[@shrujanamsyama9940]

@@Bramble20322 Never have too much water as that will slow down the cooking by a big margin. Cooker blos up due to excess steam pressure caused by the valve being blocked, not by dry heat

[@CptPatch]

I love Dan videos.

[@ammaribrahim5756]

Me too

[@gedionyitref394]

Hello from Evanston!!

[@gedionyitref394]

@Sadie Pimlott yeauhhhhhhhhhhhhhhh!

[@Soniboy84]

Can you also say the temperatures in Celsius? Literally the entire world does that except US.

[@auntlynnie]

I agree that it's RIDICULOUS that we're not using metric measurements in the 21st century in the USA, but it's an American show. When I watch British cooking shows, I do the conversions (unless it's a common temperature that I'm used to converting automatically, like 180ºC and 200ºF being roughly equivalent to 350ºF and 400ºF, respectively).

[@overseastom]

At sea level, and under normal atmosphere pressure, water boils at 100°C and freezes at 0°C, so those are easy to remember. The pressure cooker he mentioned could get the boiling point up to 121°C, but he didn't specify at what pressure that was, and which models go that high, or higher. Then again, this wasn't a product review video, just a quick explanation of how pressure cookers work. Cheers mate.

[@rezagrans1296]

Heeeehhhehh [(Temp F°)-32]×(5÷9)= Temp°C ☺

[@Bramble20322]

@@overseastom Most cookers will work between 1.6 and 2ATM (most are 2ATM), Instant Pot boils at 117ºC if i remember right, most stove top pots will boil at 120ºC.

[@carydean7389]

I’d measure with rice before I used metric fuckers

[@werallgnnadieintheend]

AMAZING DUDE , I'm so relieved that I could understand it well

[@MetaView7]

I have a question: What are the differences in results if I submerge the roast in liquid vs cooking it on a trivet above the liquid? What is the science behind it?

[@alloy299]

Technically both roasts would be cooked via convective heat transfer of a fluid at 100°C, one inside of a liquid and the other inside of a gas. In practice the fact that the trivet one is also exposed to atmospheric air means it gets mixed into the vapor stream reducing its average temperature delta with the roast surface, therefor greatly decreasing the heat transfer and making it a slower "gentler" cooking method.

[@MetaView7]

@@alloy299 Thanks for your reply . . . But 100°C ??? I thought we are talking about pressure cooking.

[@anti-ethniccleansing465]

@@MetaView7 What’s your point? That equates to 212°F.

[@MetaView7]

@@anti-ethniccleansing465 >>What’s your point? That equates to 212°F. The point is, you are not aware that pressure cooking is over 212°F.

[@Bramble20322]

@@anti-ethniccleansing465 Pressure cookers work at 110-120ºC. 100ºC is boiling temperature at 1 ATM, pressure cookers go up to 2ATM.

[@melissaroscher1080]

I still have Mom's 1970 Mirro PC hopefully they still make the seals.

[@abdulrani873]

Tq for the brief, yet easy to understand explanation ! TQVM ! ...

[@VV-dx3kt]

Not only that, the pressure cooker is mainly for legumes as it is the only thing that kills the lectins in food. Pressure cooker are not for all food. It is either for the hard to cook or the legumes. I use it for the legumes for the reason mention above but when I need to cook something fast and hard like pork legs, or read meat, then it's very useful.

[@righthandofdoom77]

They don't show America's Test Kitchen on PBS UK anymore. I miss it.

[@harveyh3696]

Unfortunate. Thankfully, we do have this forum.

[@GamerSirus]

Somebody should start Britain's Test Kitchen.

[@seikibrian8641]

If you subscribe to the ATK Web site, you can watch all 19 years' worth of the programs on your own schedule. New episodes are added once they've aired.

[@tekkenfan01]

America has everything

[@righthandofdoom77]

@@tekkenfan01 They don't have crunchy M&Ms or Greggs.

[@anshulkarnik4088]

superb explanation and very informative

[@BanilyaGorilya]

Dan is awesome. I’ve been saving up for a 6 qt. Kuhn Rikon for a year now. Now where to put it.

[@angelferrara1440]

That's awesome✨ Temperature is really important for cooking😉 Very impressive the way Chef Dan explains about this important point👍✨ Thank you for this Great channel and its Excellent Team. Big Fan of yours, Chef Dan. A server From NYC Restaurants, Angel Ferrara☺✨

[@chairshoe81]

i live in boulder and you can try cooking beans in a pot on the stove for days and theyll never ever fully cook and always be crunchy

[@piratapan]

I bought mine at IKEA for $50, boils my beans every week and it saves me tons of time and money, used it more than 200 times now and still going s if it were brand new.

[@MrsOrrDiaries]

I haven't use a pressure cooker for the last 30+years. Bought 1 last week and trying to see how it works and what to expect. Will be my first time

[@mikema9311]

Short and sweet explanation..thxs

[@daniel26395]

Even though I'm American when I heard Dan say the temp of boiling water in Fahrenheit I was confused for a sec. I've never forgotten the boiling point of water in Celsius (at STP) but I can never remember what it is in Fahrenheit even though I've learned it 5+ times.

[@Amor_fati.Memento_Mori]

Um... Wtf was that ending. White shirt girl: "see you later"🤗 Black Shirt girl: "I'll See you later"🌝

[@AdamasFR]

Thanks a lot for this video, it's really clear.

[@mnasirkhanctl]

Whoever invented pressure cooker was a real genious

[@erimali9650]

Can I use electric pressure cooker to cook lamb but without adding water ! Is it safe to do so and how long does it take to cook

[@jasoncarrie-annbreitkreuz4927]

Works awesome ... I use it to make beans (pre-soak over night to cook on high for 10 minutes then heat off natural release for 20 minutes)

[@kohort1]

Does anyone like me want to see an instant pot test comparing the low and high pressure setting, the cook time on an equal size beef, or the fully submerged vs half submerged?

[@BD-zg7is]

short perfect video. thank you. this should be the #1 result on google

[@talla2315]

Would you please make a demo on pressure cookers? Only because I have one and don't really know how to use it . It's an over the stovetop one . The other day I used it to make soup and everything went everywhere. Mary I had it too high or too much water. Thank you and I love every one of you ,you are all unique in your own way

[@anthonyrosa5006]

Never fill it over 3/4 full , never with stuff that can spash and block the valve, use moderate heat to get the cooker to produce steam and then LOWER the flame to the minimum needed to get a small amount of constant steam ( my electric stove stays on the lowest setting to maintain a head of steam but this new Fissler pressure cooker leaks the least), a jiggling weight can sometimes be the sign on some models, others just let small amounts of steam out others have some sort of pressure indicator. The best cookers maintain closest to 15 lbs and 250 degrees and do not allow too much steam out and have heavy bottoms. A good cooker is pricey and a lifetime investment. Some can be fully rebuilt with new parts.

[@danielherrera9729]

Informative with a very nice presentation

[@Bnizzofashizzo]

One thing I will say to you is, a stove top pressure cooker which is infinitely safer today than it was 50 or 60 years ago, is far superior than an Insta pot

[@courtmanr]

great video, thanks. short and sweet

[@seamuswarren]

How does the density within the pressurised compartment impact the cooking process? Over time, less heat is needed to maintain pressure. Is this a sign the contents has reached equilibrium? I am hoping “equilibrium” allows fine tuning a “set and forget” simmering temperature.

[@seamuswarren]

I addressed to enquiry to “Deep Thought”: The density within a pressurized compartment can impact the cooking process in several ways: 1. Heat transfer: The density of the contents affects how efficiently heat is transferred throughout the food. Denser foods may require more time to heat evenly compared to less dense foods. 2. Pressure and boiling point: Increasing the density within the pressurized compartment raises the pressure, which in turn raises the boiling point of water. This can result in faster cooking times, as food cooks at higher temperatures under pressure. 3. Equilibrium: When less heat is needed to maintain pressure over time, it can indicate that the contents have reached equilibrium. In the context of cooking, this means that the temperature and pressure have stabilized, and the food is cooking at a consistent rate. Achieving equilibrium in the cooking process allows for more precise control over simmering temperatures, making it easier to maintain a steady temperature for extended periods. This can be especially useful for dishes that require slow, even cooking, as it allows for a “set and forget” approach where you can simmer food without constant monitoring.

[@surfsaladsleep9556]

thanks so much! very informative and to the point! learned something new :)

[@uwarrior]

Concise and informative

[@mak7t793]

Thank you !

[@mitzimarquez2410]

Awesome. I have a pressure cooker but need to dust it off. Would appreciate how you all compare a pressure cooker compared to the instapot.

[@thegoodplate]

They're basically the same thing. The Instant Pot has a few more functions, but I use it almost exclusively for pressure cooking. What's nice about the Instant Pot is it doesn't take up room on your stove, it can go anywhere there's an electric plug.

[@wwoods66]

The Instapot runs at a slightly lower pressure, so it only heats to 240°F(?). So it takes a little longer to cook (5-10%?).

[@auntlynnie]

I have both a stovetop pressure cooker and an Instant Pot. They have similar results and I love them both. I agree 100% with the two people who have replied to you already: the stovetop model cooks a tiny bit hotter/faster, but it takes up a burner. I can put my IP anywhere there's an outlet (doesn't even have to be in the kitchen) and it feels a little more hands-off. I love the timer function; it shuts off at the time I told it to -- whereas I have to remember to turn off the stovetop model. If I'm cooking a lot of dishes simultaneously, the IP keeps me sane.

[@HigherGold6]

Thank you.

[@ForteGX]

If cooking time isn't an issue, how does a pressure cooker pot roast compare to a slow cooker? Obviously a slow cooker pot roast would be underdone in 1 hour. However, what if the slow cooker was given 7-8 hours? Would there be a noticeable difference between them?

[@overseastom]

Pressure cooker version will be better. At the higher temps in a pressure cooker, you actually get the Maillard reaction occuring (ie, browning will occur), even though it's an extremely moist environment. The pressure cooker can easily replace your slow cooker.

[@moilois734]

great explanation! thanks

[@tridsonline]

I have 2 pressure cookers that i would like to compare for maximum pressure. Can you think of some way to measure the actual pressure of each one (not just the claims of the manufacturer), so that i can make informed decisions when i need to use one? If not measure in actual psi/kPa, then some way to compare so that i know which one reaches a higher pressure?

[@jamescombs2118]

oh man my mouth is watering

[@semco72057]

I have the Instant Pot which I have never used, but keep saying I will use, but we still have my mother's old pressure cooker which is collecting dust since I don't cook much with it, nor does anyone else. Thanks for the test results and I hope you all had a great July 4th.

[@auntlynnie]

I would advise trying something cheap first. I love making roasts and stews, but it's scary to start with a big cut of meat. I made potato salad with my Instant Pot yesterday. Diced up red potatoes (skin on, pretty small dice). Put a cup of water in the Instant Pot and then put the potatoes in a steamer basket. Sprinkled the spuds with a healthy couple of pinches of kosher salt. 3 minutes on high pressure, wait 5 minutes after the timer beeps, then release the pressure. Perfectly cooked and didn't heat up the kitchen with a ton of escaping steam. (If you cut your potatoes into larger chunks, you'll need to cook for 4-5 minutes.) If your potatoes aren't fully cooked when you crack open the pot, just re-seal the lid and cook for another minute. Since the pot is already hot, it doesn't take too long to get back to pressure. Bonus: If you like eggs in your potato salad, just plop them on top of the potatoes. They'll be pretty perfect in the same amount of time, and cooking them at pressure somehow makes them easier to peel. If you're making potato salad for a crowd, you may need to do a couple of batches, but if you have the potatoes ready, you can dump the cooked potatoes into a bowl, change the water, and re-fill the steamer with the next bunch of raw potatoes, and re-seal. Again... the pot's still hot, so it won't take too long to get back up to pressure. If you don't like potato salad, this is the first step to making awesome red-skinned mashed potatoes. Just add cream and butter instead of mayo and mustard.

[@semco72057]

@@auntlynnie That sounds great and I have to try cooking a roast and see how it turns out. The salad sounds great also.

[@dimitribelissario7122]

The boiling point in a pressure cooking pot is lower than 100C The cooking pots until 1960s was calling lower pressure pots and were using for canning because there are producing steam easily. The pots actually are a vaccum chamber .The argument with between ecoteric pressure and atmostheric pressure is not valid here.The first pressure is a variable and the other is constant.In a Lower pressure pots in which we are cooking food in Higher pressure we have two variables.Lower boiling point ,most steam ,most moist food with more nutrients.

[@michaeljackson1388]

Thanks that was helpful.

[@joemug4079]

How high does the burner need to be? Should the pressure regulator need to jiggle slowly, or moderately, or fast? No one ever mentions this.

[@igot2020vision]

Has anyone ever used a pressure cooker to cook a burrito? If not I'm trying it today so I'll let you know how it goes.

[@igot2020vision]

Okay, I do not recommend anyone pressure cooking a burrito, it didn't go well. The tortilla got very soft so I had to air fry it to retain structural integrity. I had put the burrito on a piece of foil, without it, the burrito would have fallen through the bars of the pressure cooker shelf. We tried.

[@Bramble20322]

@@igot2020vision It works by pressurizing steam, so that's to be expected. Everything in it will be soggy.

[@jordanpaz4205]

Awesome stuff, thanks for the vid 💯

[@jeffbacon5174]

Can't wait to try it.

[@ImTheDudeMan471]

I love my stainless steel Hawkins for beans, beef and pork roasts and whole chickens.

[@CaptainRScott]

They didn't address Pressure Cookery (PC) @ CIA from what i can remember. I would love to see more PC recipes on ATC Thank you, lov ya

[@wemcal]

Great information

[@fu8713]

Short and sweet The best 👍👍

[@fullyvictorious]

Dan is great

[@michellemc9517]

Thx bro

[@bwisanggeni]

That's enlightening ❤️

[@ReallyNo.01]

Wow

[@alanvonau278]

It looks like it's about time to have a Dan fan club 👍😉

[@rebeccacherry-healingcarer8412]

Hi wondering if you can help me I need a new top handle for my 6L Fagor Duo do you know where I can get one?

[@anthonyg.9159]

So the higher the flame, the hotter it gets? I’m having a hard time understanding how these work as well as the weights on the pressure cookers. I’m assuming the higher the flame I use, the hotter the water is going to get internally.

[@da4127]

the faster it heats yes, but water has a maximum temperatura it can reach, if it starts to boil, it cannot get any hotter because the energy is then used not to heat the water but to turn it into vapour. Simply put, a pressure cooker makes water boil at a higher temperature because the more pressure, the harder it is for water to turn into vapour.

[@Bramble20322]

Pressure cookers work at a maximum set pressure, usually up to 2ATM. The water will heat till its boiling pot at 2ATM (~120ºC) then it will evaporate, maintaining that temperature until all water is gone. You can increase the velocity that water boils (therefore the amount of steam expelled by the pot through the valve), but the temperature and pressure will remain at its max of 120-121ºC.

[@Mcjiggles640]

Dang A video about a pressure cooker in Boston where the massacre was caused by a pressure cooker

[@StyngRay1]

Which pressure cooker cooks the fastest

[@MetaView7]

How is the meat affected by quick release vs natural release?

[@deyesed]

MetaView7 carryover cooking from natural release gives a bigger window of time for perfect doneness, especially for larger pieces. Otherwise I can’t think of a big difference.

[@MetaView7]

@@deyesed I am wondering if the sudden decrease in pressure will change the meat texture? Will the "vacuum" causes the meat to lose moisture?

[@auntlynnie]

FWIW, my understanding is that a natural release is better for keeping meat tender. I don't know why, and I haven't tested it, as I don't have an unlimited budget for meats, so I always go with at least a partial natural release if I'm cooking meat (let it go on a natural release for at least 10 minutes, then release the pressure -- but I prefer to allow a roast to go on a full natural release). In my mind, it's akin to allowing steak to rest before cutting it.

[@madthumbs1564]

There's another kind of quick release; running cool water over the lid in the sink. - Less volatile than quick release and cannot be done on IPs.

[@ahmedjinan6600]

What is this Fahrenheit that you speak of

[@shubhamcharlu605]

Shoutout to those who forget to keep a watch on the whistles when told by their moms 😂😂

[@user-qc5je7cq9k]

how much

[@uncledibby]

the pressure cooker roast still needed another 30 mins

[@micahthornton3259]

Great video!

[@jeffthevideoguy23]

Why do you say that we can access your recipes online, then block out the recipes unless we subscribe?

[@HassanKhan-sx1nt]

i still not got answer that what cause atmospheric pressure inside cooker to raise than 760torr

[@reginadandridge4618]

Please help me with cooking time with pressure cooker Ribs in high altitude!

[@danielfreire1672]

vim pela aula de quimica

[@souhailshamaissem7564]

Top video nice short and informative

[@HowToJelly]

cool video.

[@MrWackozacko]

Farenheit? On to the next video with accurate measurements

[@Alteori]

1:26 oh dear god....... oh my...... see.... this is why I struggle with going vegan.

[@johnsmith-qe2fd]

Now I want roast

[@KGopidas]

Does it mean if we reduce pressure inside the cooker pressure is reduced, water would boil at lower temperatures?

[@salmanalmahoozi4124]

what is the dangers of the pressure cooker and how to avoid them?

[@salmanalmahoozi4124]

@@ArtU4All Natasha, thank you for your answers,but as they are .experts at kitchen I think their advice more useful than the manual.

[@anthonyrosa5006]

Dont overfill, dont use too much heat. Read the manual. I never had any problem other than using too much heat and scalding the bottom on a cheap aluminum PC.

[@anthonyrosa5006]

@@salmanalmahoozi4124 Honestly, The manual for YOUR pressure cooker is THE BEST source for safely operating YOUR pressure cooker. That advice is sound advice. Nobody can tell you that in text or in a 3 minute video. In general what I said below stands for all cookers. The manufacturers want you to have a positive and SAFE experience, read the manual.

[@salmanalmahoozi4124]

@@anthonyrosa5006 Hi Anthony I'll trust your advice and going to buy one. Thanks and regards, Salman,

[@BSGA22]

Cool.

[@nelsonsilva5435]

If an Indian recipe says turn off the pressure cooker after the 3rd whistle, what do they mean?

[@ishtar0077]

Yes video with him.💖😊

[@Topself24]

Higher temperatures don’t burn the food?

[@StewieGriffin505]

No, it can burn as long as you have enough liquid in the pot. Think of it as superheated boiling water.

[@Topself24]

@@StewieGriffin505 ok thank you

[@howardlam6181]

why is no one measuring the actual pressure level of these cookers? It's impossible to find whether they do false advertising like we do with computers. All computers have all sort of benchmarks to compare different products but not these cookers

[@LuminousFigurePainters]

But they didn’t compare a pot roast cooked traditionally vs in a pressure cooker. There has to be a difference, right?

[@forte210392]

What would be a better comparison though?

[@anthonyrosa5006]

Thats EXACTLY what they did.

[@Bramble20322]

There will be differences, but in a conventional roast you'll be using 10 to 20x more energy and time, so that's a question of priorities, i guess. I find the pressure cooker results good enough that taking 6 hours to cook something just isnt worth it.

[@arah6783]

I need this to save electricity too. I could be boiling meat for two hours and still tough

[@lunes-1]

👌

[@johnlord8337]

Best option for a pressure cooker is the double layer Kuhn-Rikon steamer basket ($30 Bed Bath). Can do all kinds of pressure-steaming less time, less energy, steaming saves nutrients and calories vs cooking/boiling destroys HALF ! Steam cook, then hot-air dehydrate any grains, herbs/vegs/vegetti, (even meats and jerky) for jar meals with pre-cooked grains, beans, meats, vegs, spices, sauce powders etc, ... or vakpakking for prepper/hiking/camping meals.

[@user-pq8yi8yy2g]

i have a hw about science [Summarize in no less than 25 words what is the role of a pressure cooker.] can you help me plz

[@evangaudet]

High or Low?