Stock in a Pressure Cooker

[Rachel Perlow]

I am surprised by the color of your stovetop simmered stock. Off-white means that it boiled too hard and the fat got emulsified into the stock. I think your simmer wasn't gentle enough, you should barely get any bubbles.

[Katherine]

I am surprised by the color of your stovetop simmered stock. Off-white means that it boiled too hard and the fat got emulsified into the stock. I think your simmer wasn't gentle enough, you should barely get any bubbles.

The flame on my stove burners goes quite low, but YMMV.

Let us know how yours compare under similar conditions.

[JayBassin]

Classic stock making requires long, slow simmering either uncovered or with a paper lid. In a restaurant kitchen, this makes sense because there's a constant need for stock and you can toss in veg scraps as you prep. In a home kitchen, for "batch" processing, it's less practical. I've been making stocks in my 12 qt pressure cooker for a couple of years.

I blanch the bones first (for a white stock) or roast them (for a brown stock), but then all the bones, veg, herbs, and spices go in. I bring the pressure up to the second mark (15 psi) and -- imortantly -- let the pot cool slowly to avoid any boiling. Strain everything through a chinois.

I believe the pressure prevents boiling (as long as the pressure relief valve stays closed), and as long as the pressure reduces slowly. I find I can get pretty clear stock in only a couple of hours.

Does anyone else do this, or have other experience?

[Milagai]

I make veg stock all the time in a pc,

and freeze excess.

Don't want to fuss making any other way.

Get results that I like, I have nothing to compare

it with though....

Milagai

[peppyre]

My grandma used to make all of her stock in the pressure cooker, in fact, she would throw in a whole chicken along with the veggies and anything else, and the end result would be dog food and marvelous stock. She used to cook it so long that the chicken bones crumbled and were put into the dog's food. (That was always my job). My mom also uses her pressure cooker for stock but doesn't cook it as long as my grandma used to. It works very very well for home use.

[anzu]

I always use the pressure cooker too. But the softened chicken bones are usually eaten as the cook's treat.

[fiftydollars]

They say you'll get a cloudy stock that way, but it sure beats a can of Swanson's. Yes, it's not as clear and tastes different than a traditional stock, but it's very flavorful, fast, and homemade.

[Milagai]

They say you'll get a cloudy stock that way, but it sure beats a can of Swanson's. Yes, it's not as clear and tastes different than a traditional stock, but it's very flavorful, fast, and homemade.

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serious question: once incorporated into a finished dish,

can you really discern these differences?

milagai

[JayBassin]

They say you'll get a cloudy stock that way, but it sure beats a can of Swanson's. Yes, it's not as clear and tastes different than a traditional stock, but it's very flavorful, fast, and homemade.

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I've found that if you don't allow the pressure cooker to vent (either by increasing heat/pressure too high or by pressing the manual vent-release), the contents can't boil and therefore the stock won't cloud. I know the conventional wisdom is that pressure cooking = cloudy stock, but I don't think it's necessarily true.

Milagai's point is also well-taken: Depending on the finished dish, it may not be discernable. I've also taken the next step by clarifying the stock afterwards, if I needed a crystal-clear base. The real key is to chill the stock and take off the congealed fat before reducing.

Finally (??), it's important to note that modern pressure-cookers don't vent enough steam to reduce the stock during the procedure. Conventional simmering will reduce and concentrate the stock during simmering. Consequently, you should add less water to the cooker before sealing it than you would if you were simmering it in an open pot.

[fiftydollars]

You guys are right and a little cloudiness in the stock won’t matter for whatever it is I’m usually doing. It’s not like it’s going to cloud my risotto.

It’s also not going to make any difference whether the stock boils violently while I make it or while I’m braising something. I like to braise short ribs in a little stock and wine for about 2.5 hours at 325. Therefore the sauces I make with braising liquid are never that clear at all anyway.

You can blame Jaques Pepin for my phobia of cloudy stock. In his Complete Techniques I believe he writes that boiling clouds the stock and makes it less digestible. Of course, as I read it I could hear his voice admonishing me with a French accent and at the time I swore I would not let such a terrible thing as cloudy, poorly digestible stock happen to me.

And I never really thought about keeping the pressure cooker below a boil (Duh!). Thanks for the tip, JayBassin.

I’ll have to put the pressure cooker back into my stock-making rotation.

[scott123]

You can blame Jaques Pepin for my phobia of cloudy stock. In his Complete Techniques I believe he writes that boiling clouds the stock and makes it less digestible.

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Sorry Jacques, but I'm not buying it. Tell me it's unpalatable and I may think twice about boiling. Tell me it's undigestible and I either start asking for degrees and/or double blind studies.

I have no degree nor have done any studies, but from my own experience, I'll put money on it- chicken stock is one of the most digestible foods on the planet, clear or cloudy.

And, while we're on the topic, I'll go one step further and commit complete culinary heresy by stating that skimming stock is utter crap. There, I said it. Describe, if you will, the difference in compounds extracted from bones/flesh boiled in water and bones/flesh roasted in an oven. The exact same stuff oozes out. Is there anything the least bit unpalatable about fond? NO. Do we skim the fond? The thought is ridiculous. And yet we're supposed to bust our humps skimming stock. The way in which people speak of 'impurities' in bones you would think the bones were contaminated with feces. Puh-lease. Scum certainly has an unpalatable sounding name and it looks kind of nasty sitting on top of the pot, but if left unskimmed, scum has zero negative impact on the taste of the stock. Nada.

[JayBassin]

You can blame Jaques Pepin for my phobia of cloudy stock. In his Complete Techniques I believe he writes that boiling clouds the stock and makes it less digestible. Of course, as I read it I could hear his voice admonishing me with a French accent and at the time I swore I would not let such a terrible thing as cloudy, poorly digestible stock happen to me.

←

I think that if you boil water vigorously with fatty meat/bones, the melted fat and proteins will emulsify, thus clouding the stock. Because you can't get the emulsified fat out of the stock, perhaps Pepin meant that the resulting stock will have a higher fat content (fat is not as easily digestible as protein).

If your goal is to make a clear soup with the stock, then avoiding cloudiness is smart. If you plan to make risotto, or gravy, or short ribs, doesn't matter.

Anyway, I make a gallon of stock at a time, and freeze it in 1 qt batches. Because I usually don't know what I will do with it, I don't salt it and I try to make it as clear as practical. As I said in my intro to this topic, blanching (and rinsing) or roasting bones will denature the proteins and minimize cloudiness. Also, keeping the heat to the pressure cooker just so you never hear that hissing, venting sound will prevent the stock from boiling and hence clouding the stock.

[alexw]

Stocks can be made very successfully in a pc, but due to the increase in temperature (aroud 130+C) the fat effectively "montes" it's way into the liquid. Heston gets around this with a special filtration device which is non-protien attracting, so the protien rich stock pours through whilst all the other crap stays put.

He has used this technique in short show demos, perfect quail stock in a half hour. Deep fry your quail, add boiling water and aromatics, put the lid on and cook for 25 minutes, pass through said filter and hey presto, clever but personally I like to watch my stock develop (a bit old school sometimes me!), but have done a very nice lobster stock in my pc and the flavour is incredibly intense.

Alex.

[Richard Kilgore]

Stocks can be made very successfully in a pc, but due to the increase in temperature (aroud 130+C) the fat effectively "montes" it's way into the liquid. Heston gets around this with a special filtration device which is non-protien attracting, so the protien rich stock pours through whilst all the other crap stays put.

He has used this technique in short show demos, perfect quail stock in a half hour. Deep fry your quail, add boiling water and aromatics, put the lid on and cook for 25 minutes, pass through said filter and hey presto, clever but personally I like to watch my stock develop (a bit old school sometimes me!), but have done a very nice lobster stock in my pc and the flavour is incredibly intense.

Alex.

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Interesting. Can you tell us more about this special filtration device? What is the cost and is there an on-line source?

[Mr Wozencroft]

The "special filtration device" is coffee filter paper, dig?

[jefferyc]

How long does it take to make stock this way? My chicken stock takes 6 hours now.

[Shalmanese]

Chicken stock takes less than an hour in a PC and the bones come out crumbly which means all the gelatin has been leeched out. If you want a lighter stock, then you might have to experiment a bit with shorter cooking times.

However, because there is very little steam leakage, your stock won't reduce. What I like to do to maximise yield is to stuff the PC full of chicken bones only and make a bone only stock and then strain it and then simmer it in a pot with some finely diced mirepoix for about 30 minutes to reduce it an infuse it with vegtable flavour. That way, you get more stock per batch.

[Abra]

Shalmanese, I'm trying your two-step stock right now. I've never done that exact trick and I have a couple of chicken carcasses that needed to get into the pot.

[phan1]

What are your thoughts on using a pressure cooker for stock? I'm a big fan of Heston Blumenthal, and he loves using a PC for stock. He uses it a lot in his "In Search of Perfection" series, where the recipes are definitely not made with shortcuts in mind. So why doubt the man?

I have NEVER read anything from reputable cooks/chefs about using a PC for stock. If using a PC was so great, wouldn't everyone do it? Who would want to wait 10 hours to make stock? Restaurants would especially benefit from having huge PCs in their kitchen, since stock is such a painful ongoing process. Heston does some other questionable/unclassical things too...

For example, in his "perfect fish pie" he makes a seafood stock for the fish. He 1st makes a fish stock with veggies, fish flesh, and bones and puts them in a PC for 30 minutes. He then adds in the roasted langustine tails, more veggies, and cooks them in a PC again for another 30 mins. That's like making seafood stock for 5 hours using a normal stock pot! There's no way you make a seafood stock for 5 hours in a normal stock pot; the flavors will start to deteriorate! He then proceeds to add cream, egg yolks, and agar agar to thicken the stock into a sauce. No reduction. Classically, a cook would reduce the stock, add cream, then reduce again. You get a thick sauce, no need for egg yolks or agar agar. Any thoughts on this part?

In the end, using a PC does make sense to me. You get less flavor loss from boiling off your stock, and the higher heat would probably aid in flavor extraction. The short cooking time might also mean that you can't overcook the flavor of your stock. But it might also lead to muddy stock. But in the end, if it was better, wouldn't everyone else be doing it?

Edited February 28, 2008 by phan1 (log)

[maher]

i use one for stock quite a bit. as you point out clarification is the biggest issue, but the flavor is fantastic.

i strain the stock then reheat and clarify, which is a bit of a pain, but i feel the speed and more importantly the flavor of the stock is well worth it.

[Zeke]

I saw Alton Brown make beef broth with a PC on Good Eats. Apparently it's just as good and saves time. I rarely make my own stock or broth so I haven't tried it.

[RAHiggins1]

I'm trying it right now. I had 2 turkey carcasses from fried turkeys at Thanksgiving waiting for me to pick them clean and make a dark turkey stock to substitute for my nonbeefeater friends and wife.

This is a 22 quart pressure cooker.

I roasted the bones to get them nice and dark.

Mirepoix, peppercorns, bouquet garni, and 5 gallons water.

Lid is on, lets see what happens. My stove is an older hot surface type, so it will take awhile to get rolling.

[jackal10]

I use one alll the time. Often you dont want or need a clear stock, and if you do the freeze (it has enough gelatine) and melt slowly in a cloth lined sieve or coffee filter. Easy.

[KennethT]

The problem with using pressure cookers for stock is if you rapidly release the pressure after cooking, the mixture will boil violently until the 250degF is reduced to under 212degF - this will surely homogenize any impurities/fat into the stock...

I actually use a pc to make stocks and broths all the time... and it is possible to make a remarkably clear stock/broth with it... with consomme clarity...

My steps take a little bit longer, but I think, in the end, the result is worth it - I have never tasted any "vegetal" flavor or other off note that has been described above... also, i don't blanch or wash the bones prior because I think it leaches out flavor...

What I do is put the bones/meat in the pc with the lid off (white stock uses raw bones/meat, brown stock uses roasted bones/meat)... cover with the total amount of water being used.... I bring to a simmer (lid off) skimming all the way... once it comes to a point where no more impurities (or very little) come off, I add the vegetables/bouquet garni, then the lid and increase the heat so that I get full pressure - once at full pressure, I decrease the heat to maintain a bare simmer inside the pot - you can tell the simmer level by listening to the pot - you can hear how fast it boils... also you can tell sometimes depending on how much steam comes out of the release valve - you want it barely steaming at all, while maintaining full pressure.

Chicken stock I let go this way for 1/2 hour, beef/veal stock I let go for 1 hour.

Then, I turn off the heat and allow the stock to "steep" until cooled enough so that there is no more pressure in the pc... this takes a few hours - once sufficiently cooled, I remove the lid and strain through a strainer lined with cheesecloth, trying to disturb the bones/meat as little as possible. I have no bacterial concerns since 1)everything has been killed while at 250degF for 1/2 - 1 hour and nothing has been re-introducted usually around 180degF).

I then cool the strained stock in a sink full of cold water to cool as rapidly as possible, then leave uncovered in the refrigerator overnight... the next day, you can remove the congealed layer of fat from the now "stock jello"... I'll then reheat and either concentrate for storage, or store in the freezer as is...

I think the key to the clarity is the skimming prior to pressurization, gentle simmering during pressurization, and slow cooling....

[nickrey]

Intrigued by the concept of pressure cooked stock, I had to try the recipe for Chicken stock from the Big Fat Duck Cookbook.

As he does in a number of recipes, Heston made the flavour profile more complex by using the central ingredient in a few different ways (he sometimes slow cooks onion with other ingredients and then adds some more at a later stage to give a different texture and flavour).

The stock was made by first cooking the vegetables and chicken in what was essentially a typical pressure-cooked stock (with skimming prior to the pressure cooking). This was then cooled naturally, opened and more chicken added for a second cooking. The aromatics were added after cooking to steep into the mixture. The result was perhaps the most flavoursome and complex chicken stock I've made.

As noted by many people above, the secret for a clear stock made in this manner appears to be to not allow the pressure cooker to come to a boil (ie. to keep the pressure cooker at a temperature that cooks but does not open the steam valve on top).