Pressure cooker vs cooking sous vide for stew, braise, etc.

[EnriqueB]

Thanks, Anna N, rotuts, ePressureCooker, I'm glad my comment was useful.

[Keith_W]

But, organoleptically, the meat is completelly different from the 60ºC one. Juiciness and colour changes take place up to around 75ºC, any higher temperature will not change things much for them, whereas the hidrolysis of collagen takes place exponentially faster as we continue to increase temperature. That's why the traditional stew will not be so much different from the pressure-cooked one at around 120ºC, but can be cooked much faster.

I think this is the key insight into the difference in texture between SV and PC.

[Syzygies]

I have a high-end pressure cooker, sous vide equipment, and various clay cooking vessels such as tagines and bean pots.

I bought the pressure cooker to follow Heston Blumenthal. Stews tasted institutional from it, and I only use it now for beets. Even this is a compromise, as an oven-roasted beet is better.

Sous vide can and should be a clinical triumph, yet I'm drawn back to the clay. I want to believe nothing beats a tagine, but in fact my favorite stews have come from the "tangia" approach (so far, using bean pots), using very little liquid. Place pot in 450 F oven, immediately turn down to 250 F, cook up to five hours, to replicate a tangia left in the ashes at a Moroccan bath house.

Looking at texture is focusing on "what is" rather than "what isn't". What's missing from the more clinical approaches are variations in texture, and the effects of reduction.

[jayt90]

The complaints I'm seeing here about pressure cookers seem to be (1) muddied flavors. (2) stringy meat.

These can occur from overcooking and adding too many ingredients.

For a traditional beef stew, I'll size up vegetables and chunks of meat to cook to completion at the same time. For example, beef chunks from a Costco tray can mix with halves of carrots, onions, and russets, but parsnips and yams would have to be chunk sized. The broth when finished will make a fine sauce, not expected to be clear. This will cook in 25 minutes. More time and the beef is stringy.

I have looked at short term PC cooking, and it almost always works.

I cooked de Cecco spaghetti last night for 15 minutes, more than the time recommended on the package, and it was perfect. This brand seems to need intense heat and lots of time.

Lobsters are a favorite PC item for me. I can toss in two or even three, with a trivet on the bottom, and steam at high pressure for 10 minutes. It takes that amount of time to cook through, and the lobsters come out very hot but succulent.

One thing I won't do in a PC is a roast. It takes a long time to cook through, and the outside will be overdone. That might be better in sous vide.

Ruhlman has a fine recipe for vegetable stock in Ratio, and I can do this in 25 minutes. More time, and the delicate flavor and color is lost.

Fish stock is also a revelation. I use the carcasses and a large fish head, jam them in, and PC for 25 minutes with aromatics. Results are clear, gelatinous and full of flavor.

Come to think of it, I rarely PC for more than 50 minutes. It all depends on the size and texture of the things going in.

[Baselerd]

I prefer sous vide for "braises" because it is dead simple and gives you the exact texture you want (whereas you don't have much control with the pressure cooker). The meat comes out super flavorful, and often the liquid/jelly left in the bag can be used as a flavor booster in sauces, stocks, etc. Not very good for a single pot stew since the veggies need to cook at higher temps and for less time, but this further illustrates the weaknesses of traditional methods (meat cooked at too high of a temperature / vegetables cooked for too long).

Pressure cookers work pretty well for stews so long as you want a more flakey/stringy meat texture - which works great for chili, pulled pork, etc.

[rotuts]

Lobsters are a favorite PC item for me..

many Fish restaurants on Cape Cod have full sized industrial autoclaves, sort of like PC. they cook all their lobsters in them, both for the restaurant and "To Go"

they are delicious. but i cant give you any more info on time, temp, pressure etc. they have never been tough or over cooked in my limited experience.

Edited October 1, 2013 by rotuts (log)

[dcarch]

Lobsters are a favorite PC item for me..

many Fish restaurants on Cape Cod have full sized industrial autoclaves, sort of like PC. they cook all their lobsters in them, both for the restaurant and "To Go"

they are delicious. but i cant give you any more info on time, temp, pressure etc. they have never been tough or over cooked in my limited experience.

I don't know much about this either, other than the fact that autoclaves are required to be filled with steam to facilitate better heat transfer. For the purpose of lobster cooking it is possible that they reduce the pressure and temperature, so that the lobster with not be overcooked.

dcarch

[rotuts]

Ive used Autoclaves 'professionally' some time ago. I can tell you that in the medical setting, they 'boil' liquid, ie culture media.

you never will those 'flasks' more than 1/2 full to allow for this.

in the Restaurant? ...

[ePressureCooker]

+1 on the thank you to Enrique for that explanation. Very interesting.

There are essential differences between the methods. First, the chemical reactions taking place in tough meats at 60 and 120ºC are the main difference. At 60ºC juiciness and colour are retained, but it takes absurd times to transform collagen to gelatine. If you are willing to wait that time, the result is, IMO, incredible, with a mixture of features of traditional tender meat (redness, juiciness, tenderness) and the stronger taste of a tough cut and the nice mouthfeel of gelatine. Increasing temperature starts to draw moisture out of the meat and the red colour turns to brownish/grey. This is only compensated in traditional stews by the transformation of collagen to gelatine, which makes the meat "feel" tender at the mouth. But, organoleptically, the meat is completelly different from the 60ºC one. Juiciness and colour changes take place up to around 75ºC, any higher temperature will not change things much for them, whereas the hidrolysis of collagen takes place exponentially faster as we continue to increase temperature. That's why the traditional stew will not be so much different from the pressure-cooked one at around 120ºC, but can be cooked much faster.

But when cooking at 60ºC you don't produce the wonderful sauce that you get at 80ºC and higher, as much less juice and collagen is extracted from the meat. So, if you want a result closer in that sense to a traditional stew you have to work extra to create a delicious "jelly-like" stock, and them integrate the elements somehow (but integration cannot be as good as traditional). You also cannot add vegetables to the SV bag, as they need a higher temperature to break down their pectine walls, so again you need to work out those component separatelly.

I can't provide any information as to sous vide, never having done it, but I can add re the pressure cooking and the gelatinization issue (versus traditional methods) I can always get far more gelatinized stock than I can ever manage with stovetop methods. Pressure cook chicken bones and scraps for 90 minutes to make stock, and its going to be practically rock hard from the gelatin after refrigeration overnight. Cook a whole chicken for 20 - 25 minutes in the pressure cooker, and the cooking liquid is going to be pretty firm, after refrigeration. Even if I just cook chicken parts for a few minutes, I'll get some gelatinization. I never got those kind of results from traditional cooking methods, well, unless I simmered stock for a long time, and even then, I don't remember getting so much gelatin as I do now. And gelatinization means not only connective tissues breaking down (thereby reducing what many of us would call "gristle" / inedible parts in tougher meat cuts), but increased flavor.

That's absolutelly true, ePressureCooker, and one of the reasons why stocks are better cooked in a (non-venting, spring valve) presssure cooker. Another reason is that aromatic volatiles are better retained, and yet another one that slight Maillard reactions take place, which improve flavour. In fact, "white stocks" are never "that white" in the pressure cooker. And, if you look for very subtle flavor & aroma, SV or low-temp traditional are better, for example I prefer those methods for vegetable & fish stocks.

On the other hand, for stews I don't always want the strong gelatin extraction of the pressure cooker, and I may prefer a bit less gelatin in exchange of a not-so-dry meat.

You can actually boost the Maillard reaction by changing the pH slightly by adding a small amount of baking soda (not sure if salt is required, but I always add it). I saw a reference to this technique for caramelizing vegetables in Modernist Cuisine (might have been At Home, not sure) and have been experimenting with it, then saw a reference IIRC to Nathan Myrhvold referencing increasing non-enzymatic browning by increasing alkalinity through baking soda. Cookingissues.com also had a multipart series on their testing of chicken stock made in the pressure cooker, and I seem to recall they said they even pressure cooked commercial (canned) stock to see if they got a difference. So I've tried the baking soda stock trick on canned stock for a few minutes, and sure enough, it turned a lovely dark brown color and even the taste had changed. Don't know how to describe it, but I'm definitely going to experiment with making gravy out of it. Also have started experimenting with roasts, got some darkening of the stock that I hadn't gotten before, but I think I might need to add more baking soda to compensate for the increased acidity because of the presence of the meat in the pot.

[rotuts]

very interesting. thanks