Pressure Cookers: 2011 and beyond

[Food Man Chews]

I'm sorry but I don't agree. Just using a normal pan with a tight-fitting lid increases pressure as is demonstated when the lid rises. This is why some lids have vent holes. Similarly with the tagine, whose lid is considerably heavier in proportion to it's base. It may not be as effective as a modern pressure cooker, nevertheless it is one, albeit a primitive one.

[AaronM]

A tagine is not a pressure cooker.

End of Story.

In other news: made some ad-hoc Beef Bourguignon pressure style in about 45 minutes earlier tonight.

Exceptional.

Edited April 26, 2011 by AaronM (log)

[pazzaglia]

I'm sorry but I don't agree. Just using a normal pan with a tight-fitting lid increases pressure as is demonstated when the lid rises. This is why some lids have vent holes. Similarly with the tagine, whose lid is considerably heavier in proportion to it's base. It may not be as effective as a modern pressure cooker, nevertheless it is one, albeit a primitive one.

A tagine is not a pressure cooker.

End of Story.

If I may interject here... we are talking about two things, a cooking method and a cooking appliance.

In terms of cooking methods- cooking "under pressure" - can include:

- Sous Vide

- Carotccio (packet cooking)

- Slow Cookers

- Moroccan Tajines

- And more!!

All of these cooking methods employ direct and indirect pressure at varying degrees, slow or stop evaporation (sealed or semi-sealed environment), and use the food's own liquid as the primary cooking liquid.

In terms of cooking vessels, the pressure cooker is the pan we know and love who's latest generation cooks at 8-15 PSI, but previous generations cooked at much, much lower pressures.

That is my long way of saying: you are both right.

Now, what has everyone been pressure cooking lately?

Ciao!

L

Edited April 26, 2011 by pazzaglia (log)

[cbread]

There's pressure, and there's pressure. My large roasting pan has a cover that fits nicely enough that when some moisture wets the juncture between top and bottom, heating the vessel will make a series of small bubbling sounds that signal a very very slight excess pressure inside the vessel.

But, that said, that tiny pressure is by no means enough to raise the boiling point - and thus cooking temperature - in any useful way. To obtain a useful boost over atmospheric pressure requires a sealed system that can hold a lot of pressure, enough pressure to demand a pressure release for safety reasons. Neither tagines nor my roasting pan have the slightest claim to be valid "pressure cooking" vessels.

[Paul Kierstead]

...

All of these cooking methods employ direct and indirect pressure at varying degrees, slow or stop evaporation (sealed or semi-sealed environment), and use the food's own liquid as the primary cooking liquid.

Saying they employ 'pressure' is really stretching for all of your list (including sous-vide, where the food is at atmospheric pressure) except for using a pressure cooking. We could expand the term to mean things like braising as well, but then why bother having different terms? It isn't very useful; restricting instead the term gives common ground for discussion and information.

[Food Man Chews]

Clearly nobody here seems to have used a real tagine with it's primitive valve that is sealed prior to cooking. The Turks also use a clay pot that is sealed with dough after the ingredients are placed inside, that also has a release valve that is sealed with foil. Uskup Kebap I believe it is called, which is placed on an open fire and when cooked is then broken at the table. If that and tagines aren't pressurised cooking then clearly I don't know what I'm talking about.

http://elitguvec.com.tr/Yemekler/uskupkebap.JPG

Edited April 27, 2011 by Food Man Chews (log)

[JAZ]

The only vegetables that I find it good for are artichokes. I often see recipes for things like asparagus which I find totally ridiculous as it cooks so fast using normal methods that it would easily overcook under pressure.

For asparagus, yes. But I use mine for beets and sweet potatoes all the time.

[slkinsey]

As to whether a tagine or similar traditionally lidded cooking vessels constitute "pressure cookers," the answer is quite clear: no, they don't. And this is for a simple reason: The point of a pressure cooker is not to increase the pressure. That is a side-effect of the real point of using a pressure cooker, which is to increase the temperature above the boiling point of water. The only way to do that in a "wet cooking" medium is to increase the pressure. For example, the boiling point of water under the 15 psi setting (meaning 15 psi above normal atmospheric pressure) is 122C.

There is simply no way that a clay or ceramic vessel such as a tagine could build up sufficient pressure to raise the boiling point of water any significant amount. And there is a very simple reason why this is so: the tagine would explode because the clay is not capable of withstanding any significant internal pressure. This, of course, is in addition to the fact that foods cooked in a tagine or similar vessel are typically slow-cooked below the simmer, meaning that the temperature is actually lower than 100C. Just because there is some water vapor being produced doesn't mean that the internal pressure is increasing. Similarly, a heavy lid on a pot doesn't even come close to creating enough pressure to raise the boiling point of water an easily-measurable amount. Might the pressure inside a heavy French oven at a full rolling boil be slightly higher than atmospheric pressure. Maybe an infinitesimal amount. But you would need pretty sensitive instruments to measure the difference. More to the point, it wouldn't make a bit of difference to the cooking.

I hope we've laid that to rest. Meanwhile, I'm wondering if anyone has experience pressure cooking with one of these big pressure canners, such as the All American 21.5 quart pressure canner. The reason I'm interested in this is largely for making stock. It's great to take advantage of the fast-cooking aspect of a pressure cooker for making stock, but I'd still much rather make it in large amounts that can be reduced and stored in the freezer. In addition, I'm wondering what the disadvantages might be to making smaller quantities in a larger pressure cooker. For example, if I really only wanted to make 4 quarts of something, would I be able to do this in the big All American? Perhaps with a smaller vessel inside of it? Or would I really need a traditionally-sized pressure cooker for that amount?

[tmjst]

In principle, you could build a pressure cooker that works by using a heavy lid to hold the pressure back.

But it would have to be *really* heavy.

(Warning: Math alert!)

The area of a 10" tagine lid is about 80 square inches, using the famous equation

area = (pi*d^2)/4 = 3.14*(10*10)/4 = 78.5398163 in^2

If you want to use a heavy lid to make a 15psi pressure cooker, the lid would have to weigh 15 pounds for every square inch of lid area:

weight = 80 in^2 * 15 lb/in^2, which is 1200 pounds!!!

That's slightly impractical.

A 10" lid that weighs 1 lb (which is pretty heavy for a lid!) would increase the pressure in the pot by 1 lb/80in^2, or .0125 PSI. Pressure raises the temperature about 22 degrees for every 15 PSI, so this lid would increase the temperature by only about two hundredths of a degree:

22 degrees/15psi*.0125psi = 0.01833 degrees

[pazzaglia]

In principle, you could build a pressure cooker that works by using a heavy lid to hold the pressure back.

But it would have to be *really* heavy.

(Warning: Math alert!)

The area of a 10" tagine lid is about 80 square inches, using the famous equation

area = (pi*d^2)/4 = 3.14*(10*10)/4 = 78.5398163 in^2

If you want to use a heavy lid to make a 15psi pressure cooker, the lid would have to weigh 15 pounds for every square inch of lid area:

weight = 80 in^2 * 15 lb/in^2, which is 1200 pounds!!!

That's slightly impractical.

A 10" lid that weighs 1 lb (which is pretty heavy for a lid!) would increase the pressure in the pot by 1 lb/80in^2, or .0125 PSI. Pressure raises the temperature about 22 degrees for every 15 PSI, so this lid would increase the temperature by only about two hundredths of a degree:

22 degrees/15psi*.0125psi = 0.01833 degrees

You are both incorrectly defining pressure cooking as "cooking at 15 PSI".

Pressure cookers do not operate at only 15 PSI. Most have two, even three settings. Earlier, first generation pressure cookers, only reached 6-8 PSI. I don't think it would be out of the realm of possibility that a a Tajine could at the very least reach 1 PSI - and even that, raises the boiling temperature, albeit not by much, to "pressure cook."

Ciao,

L

[slkinsey]

You are both incorrectly defining pressure cooking as "cooking at 15 PSI".

Pressure cookers do not operate at only 15 PSI. Most have two, even three settings. Earlier, first generation pressure cookers, only reached 6-8 PSI.

I am not defining "pressure cooking" as any such thing. I merely used the 15-psi-above-atmospheric-pressure example to illustrate how much the temperature goes up (22 degrees C!) under that pressure.

The point is not that the food is cooked under "some amount of pressure." Even in an open pan with no lid, everything is already under right around 14.69 psi due to atmospheric pressure. Unless, you know, you're in a very low valley or on a very high hill.

The point is also not that the temperature has been increased. There are lots of ways you can increase the temperature (although not as dramatically as with a pressure cooker) such as adding lots of dissolved solids, etc.

The point is that one uses a special pressure containing (and regulating) cooking vessel to raise the temperature of the cooking medium such that the food cooks in a substantially different way than it would at 100C/14.69 psi. Raising the temperature and pressure of a regular cooking vessel some infinitesimal amount does not constitute "pressure cooking" by the simple fact that the cooking itself is no different than it would be at 100C/14.69 psi. Your argument is like saying that you can deep fry in a tablespoon of oil.

By the way, don't be so sure that these old pressure cookers didn't have a major effect. The cooking temperature at 6 psi over atmospheric would be around 110C. That is a significant difference over cooking at atmospheric pressure at 100C.

I don't think it would be out of the realm of possibility that a a Tajine could at the very least reach 1 PSI - and even that, raises the boiling temperature, albeit not by much, to "pressure cook."

No it wouldn't raise the pressure 1 psi over atmospheric, or anything close to that. But the main problem with your argument is that you are suggesting that if you are somehow able to raise the pressure to 14.70 psi (+0.1 psi) or even to only 14.691 psi (+0.01 psi), then you are "pressure cooking." What if you boil your stew in an open pot but you are in a deep valley below sea level where the atmospheric pressure is naturally higher than 14.69 psi? Is that "pressure cooking"? What about if your local area is experiencing a high pressure weather event? Is that "pressure cooking"? Hey, the pressure in New York City right now is 14.71 psi... I should go home and pressure cook in an open pan right now! These things, by the way, would all change the pressure and the cooking temperature more than your tagine example.

The point of all this is that unless the pressure and temperature are raised sufficiently to make the food cook differently than it would under normal pressure and temperature, it's not "pressure cooking." It's just "cooking." It's also worthy of note that "pressure cooking" is a verb derived from the noun "pressure cooker." Wikipedia has a good definition of "pressure cooking" as "Pressure cooking is a method of cooking in a sealed vessel that does not permit air or liquids to escape below a preset pressure." This doesn't include tagines and parchment, etc.

[pazzaglia]

I hope we've laid that to rest. Meanwhile, I'm wondering if anyone has experience pressure cooking with one of these big pressure canners, such as the All American 21.5 quart pressure canner. The reason I'm interested in this is largely for making stock. It's great to take advantage of the fast-cooking aspect of a pressure cooker for making stock, but I'd still much rather make it in large amounts that can be reduced and stored in the freezer. In addition, I'm wondering what the disadvantages might be to making smaller quantities in a larger pressure cooker. For example, if I really only wanted to make 4 quarts of something, would I be able to do this in the big All American? Perhaps with a smaller vessel inside of it? Or would I really need a traditionally-sized pressure cooker for that amount?

Did you read the post in Cooking Issues about making stock in a canner? Their post includes a very interesting study at how the flavor changes using venting (first generation weight-modifyed and jiggly valves) and non-venting (spring valve) pressure cookers. And how, apparently, you can take it too far and "kill" the flavor.

Ciao,

L

[slkinsey]

Yea, I read that one. I'm not sure how significant I believe those differences are, or rather whether I'm that picky about stock.

[sparrowgrass]

I have a big pressure canner like the one you linked to, and it is great for stock. And when you get done, you put the stock in pint jars and can it.

Mine has a weight that jiggles.

Edited April 27, 2011 by sparrowgrass (log)

[tmjst]

It's "within the realm of possibility," but you'd still need a very heavy tagine lid. One PSI is not very much, but there's a lot of square inches in the lid. Given the example (10" in diameter), you'd still need an 80-pound lid to get 1 PSI inside the tagine, and even then only if the lid would were unvented.

1 PSI would raise the temperature by a little over 1 degree, which would hardly have an impact on the tagine inside the tagine!

[pazzaglia]

Happy to share a new method with you guys, I posted it in the Cooking techniques forum, but it's about pressure cooking (Admin, Does "Pressure Cooker" merit a tag, yet, since it is also discussed in Modernist Cuisine topic? ... here is a link to it if you missed it:

The Scorch Method in Pressure Cooking

Lots of pictures and details.

See you there!

L

[Prawncrackers]

Has anyone tried 'broasting' in their PC? I'd love to try and make some KFC style chicken at home but the thought of pressure deep frying is a little worrying. Though the recipe book you get with the Kuhn Rikon does have a recipe where you kind of shallow fry chicken, has anyone been brave enough to try this method?

[pazzaglia]

Has anyone tried 'broasting' in their PC? I'd love to try and make some KFC style chicken at home but the thought of pressure deep frying is a little worrying. Though the recipe book you get with the Kuhn Rikon does have a recipe where you kind of shallow fry chicken, has anyone been brave enough to try this method?

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.

Ciao,

L

Edited May 4, 2011 by pazzaglia (log)

[LindaK]

Interrupting the experts for a report by a pressure cooker novice.

I purchased a Fagor Duo and finally got around to giving it a test drive. I kept things very simple so I could pay attention to the equipment, not the recipe. Did I mention that I was afraid? Expecting explosions at any moment? I must have read the user manual twice before even trying. Warning: excessive description below for the benefit of other fearful newbies.

My maiden voyage with cannellini beans last night was only semi-successful due to cowardice on my part. Nervous about the cooker, nervous about using it on my high BTU range. As a result, I kept the heat too low and got spooked by steam coming out from around the operating valve, which I had not expected. The pressure indicator didn’t move, even after 5 minutes. Fearing malfunction, I shut off the heat and just let it sit for a while before opening the pot. To my surprise, the beans were almost cooked through, needing only a little more time on the stove to become tender.

A little internet research and re-reading of the manual helped me realize that the steam release was normal. So today, I bravely tried again with some risotto. This time, I fearlessly began by using medium high heat on one of my mid-BTU burners (15K) and ignored the steam (note: there really wasn’t that much). Big difference. The pressure indicator popped up in under 2 minutes (I used a timer), and the steam release stopped completely. I turned the heat to its lowest setting. Still cautious, I recalled the instructions to continue on the lowest possible heat setting w/out losing pressure. So I moved the cooker to my simmer burner and finished it there. Six minutes later, I had risotto. It still needed the last step of beating it with a little butter and cheese, but the final result was delicious. Not quite as creamy as the traditionally cooker version, but perfectly al dente, not overcooked at all.

Very exciting! Next try will be stock.

[Chris Amirault]

After spending the better part of an afternoon waiting for chana dal to cook, I threw in the towel and ordered this Presto 6Q stainless steel pressure cooker. Given the recent outlay for MC-related purchases, I decided to go inexpensive at first. Photos and info to follow.

[Kerry Beal]

So I am the proud owner of a Fagor Rapida that Anna found being thrown out. It was suffering from a burn to it's handle and pressure valve. The first set of replacement parts I ordered was mistakenly for another model so I had a bit of a wait for the correct parts to come from europe.

Tonight was it's maiden voyage - I started with a bit of water to make sure it seemed to be working - then put a couple of big artichokes on a rack and cooked them for 11 minutes. They appear to be perfectly cooked!

Can't wait to try some of the things from Ideas in Food that require a pressure cooker.

[pazzaglia]

I purchased a Fagor Duo and finally got around to giving it a test drive. I kept things very simple so I could pay attention to the equipment, not the recipe. Did I mention that I was afraid? Expecting explosions at any moment? I must have read the user manual twice before even trying. Warning: excessive description below for the benefit of other fearful newbies.

After spending the better part of an afternoon waiting for chana dal to cook, I threw in the towel and ordered this Presto 6Q stainless steel pressure cooker. Given the recent outlay for MC-related purchases, I decided to go inexpensive at first. Photos and info to follow.

So I am the proud owner of a Fagor Rapida that Anna found being thrown out. It was suffering from a burn to it's handle and pressure valve. The first set of replacement parts I ordered was mistakenly for another model so I had a bit of a wait for the correct parts to come from europe.

Linda, Chris and Kerry...

It's very exciting, for me anyway, to hear about your experiences just getting started! If you decide to follow my Pressure Cooker Beginner Basics series, I would love feedback on how you liked or did not like the series. On the web not everything is written in stone so I would like to make any modifications or updates based on your feedback. Next year, I hope to add video, too!

Obviously, I'm here too to answer any questions - even the most minute - you might have.

Congratulations!!!

L

[Kerry Beal]

Linda, Chris and Kerry...

It's very exciting, for me anyway, to hear about your experiences just getting started! If you decide to follow my Pressure Cooker Beginner Basics series, I would love feedback on how you liked or did not like the series. On the web not everything is written in stone so I would like to make any modifications or updates based on your feedback. Next year, I hope to add video, too!

Obviously, I'm here too to answer any questions - even the most minute - you might have.

Congratulations!!!

L

A great little resource - thanks for making it and pointing us to it.

One question - I notice in your first recipe for mashed spuds that you take them off the heat then vent - my pressure cooker doesn't seem to recommend venting straight off the stove - instead it suggests running under cold water first. What are your thoughts on that?

[pazzaglia]

A great little resource - thanks for making it and pointing us to it.

One question - I notice in your first recipe for mashed spuds that you take them off the heat then vent - my pressure cooker doesn't seem to recommend venting straight off the stove - instead it suggests running under cold water first. What are your thoughts on that?

Hi Kerry, the short answer is... you can do anything you want.

I primarily chose this opening method in the first lesson because I did not want to suggest anyone making their first recipe to then carry a hot pressure cooker to their kitchen sink. For many people there is still a very large fear factor related to pressure cookers so I chose that on purpose not to add any additional fear or danger to the equation.

There are three ways to open a stove-top pressure cooker and they are :

• Cold-water Quick- bringing the pressure cooker to the sink and running the pressure cooker top under under cold water being careful not to wet any of the valves (which takes about 20 seconds, but cannot be done on electrics for obvious reasons) - best for short-cooking veggies (like carrots in lesson 2) because you can open your pressure cooker quickly. The other advantage of this method is that it condenses all of the aroma in the vapor into liquid and drips it back in the pan (for example, if you were making Alinea's Pressure Cooked Turffle stock - you would want to keep every bit of this aroma!)
  
• Normal Release - releasing pressure by pushing a button, twisting a valve or liftng/removing the weight or jiggler (which takes about 1.5 to 2 minutes) - best for most uses except while cooking foamy foods- the biggest offenders being grains and beans - because the foam could either shoot out of the valve or force a grain/bean to clog the primary release hole (causing the secondary safety mechanism to kick in). This is why you might sometimes see recommendation not to cook grains or beans in electric or venting pressure cookers without modifications (like the addition of a spoon of oil), or ever - but, it's ok if you do it carefully and are aware of the possible problems.
  
• Natural Release - letting pressure release naturally from the pressure cooker by moving it to a cool burner and waiting without pushing, switching or moving anything else (depending on the fullness your pressure cooker at what level pressure you were cooking 5-15 minutes) - this is a great way to save extra energy by harnessing your pressure cooker's superior heat retention to continue cooking the foods. Best for slow-cooking foods like beans, tough cuts of meat... but I almost always use it when making tomato sauces and steaming rice (I'm working on a special article detailing a no-fail perfectly steamed rice form the pressure cooker!) Electric pressure cookers are problematic with this opening method because you cannot dismantle the bottom and remove the heat coil, it has to cool completely before the pressure begins to come down - one just needs to be aware that it will take a bit longer (sometimes up to 30 minutes) to achieve.
  

As I alluded in the Natural Release, as long as your pressure cooker is still in pressure, or in the process of loosing pressure, it is still cooking the food inside - this can be harnessed to your advantage or be a disadvantage resulting in a tasteless mush of overcooked vegetables or meat.

Have fun and enjoy your potato smash! BTW, it is sooo much better with the peels still on - but I had to make a recipe that even Europeans would cook and... you know, we peel everything and anything!

Ciao,

L

[pazzaglia]

One question ...

P.S. If there is ever a discrepancy between what your user manual says (cooking times, washing instructions, oiling or not oiling the gasket, and other recommendations) the manual should always trump any advice that you get from a book, website or forum. Pressure cooker models, even from the same manufacturer, can operate differently in minute ways so it is always important to become familiar with your user manual to note these discrepancies and follow the manufacturer's advice.

Edited May 18, 2011 by pazzaglia (log)