Jump to content
  • Welcome to the eG Forums, a service of the eGullet Society for Culinary Arts & Letters. The Society is a 501(c)3 not-for-profit organization dedicated to the advancement of the culinary arts. These advertising-free forums are provided free of charge through donations from Society members. Anyone may read the forums, but to post you must create a free account.

High Altitude Pressure Cooking and Stock Preparation


Recommended Posts

Modernist Cuisine(page 2-291 et seq.) has an extensive discussion about using pressure cookers and pressure canners to make stocks, and their conclusion is that cooking the stock at 1 bar or 15 psi over ambient, resulting in a temperature of 121C, generally produces the best results, although some recipes call for using an autoclave at temperatures up to 130C.

However, as I live in Taos, NM, at an altitude of 7000 ft/ 2133 m, some adjustment is required. To reach the same temperature, I would have to run the pressure up to 18.5 psi. Unfortunately, most pressure cookers either use "jiggle" weights or spring loaded valves which come in 5, 10 and 15psi increments. Also, most pressure cookers don't have an independent pressure gauge, and none that I am aware of have a means to actually measure the temperature of the water/steam, much less the temperature of the stock or other food you are cooking. In addition, experiments by Dave Arnold and Nils Norén have shown that pressure cookers that vent the steam cause an undesirable cloudiness in the stock, and some loss of flavor/quality, perhaps as a result of venting the aromatics. And finally, without venting steam, it is difficult to maintain a desired pressure/temperature, even with a pressure gauge, unless you are willing to stand there and monitor the pressure and adjust the gas flame.

There had to be another, better way. After discussing this with Douglas Baldwin, I bought a 25 qt. All-American Sterilizer, model 1925X, and proceeded to modify it to use a PID controller, the Sous Vide Magic (SVM) controller from Fresh Meals Solutions, to control an electric griddle to control the temperature, and a second SVM to monitor the temperature within the stock pot.

I removed the pressure regulator, fitted a T-adapter, threaded two SVM probes through it, and then reassembled the regulator. Now I can bring the water in the sterilizer to very close to the boiling point, drop in a stainless steal pot (an All-Clad Pasta Pentola) with the stock, secure the lid, and let the pressure build up. I can vent the steam manually, or not, as I see fit. And if I am canning something, I can monitor the temperature inside a jar filled with water to make sure it is getting hot enough to sterilize the food.

For further details, seehttp://freshmealssolutions.com/index.php?option=com_k2&view=item&id=71:high-altitude-pressure-cooking-and-stock-making&Itemid=100088.

Link to post
Share on other sites

Modernist Cuisine (page 2-291 et seq.) has an extensive discussion about using pressure cookers and pressure canners to make stocks, and their conclusion is that cooking the stock at 1 bar or 15 psi over ambient, resulting in a temperature of 121C, generally produces the best results, although some recipes call for using an autoclave at temperatures up to 130C.

However, as I live in Taos, NM, at an altitude of 7000 ft/ 2133 m, some adjustment is required. To reach the same temperature, I would have to run the pressure up to 18.5 psi. Unfortunately, most pressure cookers either use "jiggle" weights or spring loaded valves which come in 5, 10 and 15psi increments. Also, most pressure cookers don't have an independent pressure gauge, and none that I am aware of have a means to actually measure the temperature of the water/steam, much less the temperature of the stock or other food you are cooking. In addition, experiments by Dave Arnold and Nils Norén have shown that pressure cookers that vent the steam cause an undesirable cloudiness in the stock, and some loss of flavor/quality, perhaps as a result of venting the aromatics. And finally, without venting steam, it is difficult to maintain a desired pressure/temperature, even with a pressure gauge, unless you are willing to stand there and monitor the pressure and adjust the gas flame.

There had to be another, better way. After discussing this with Douglas Baldwin, I bought a 25 qt. All-American Sterilizer, model 1925X, and proceeded to modify it to use a PID controller, the Sous Vide Magic (SVM) controller from Fresh Meals Solutions, to control an electric griddle to control the temperature, and a second SVM to monitor the temperature within the stock pot.

I removed the pressure regulator, fitted a T-adapter, threaded two SVM probes through it, and then reassembled the regulator. Now I can bring the water in the sterilizer to very close to the boiling point, drop in a stainless steal pot (an All-Clad Pasta Pentola) with the stock, secure the lid, and let the pressure build up. I can vent the steam manually, or not, as I see fit. And if I am canning something, I can monitor the temperature inside a jar filled with water to make sure it is getting hot enough to sterilize the food.

For further details, see http://freshmealssolutions.com/index.php?option=com_k2&view=item&id=71:high-altitude-pressure-cooking-and-stock-making&Itemid=100088.

Link to post
Share on other sites

Interesting, but I wonder if all this is really necessary.

I have an WAFCO All-American pressure canner that is more or less the same thing you have, with a different top. Stocks don't strike be as acidic enough to particularly worry about the fact that it's made of aluminum, and none of the stocks I have made in there have suffered from metallic taste. So putting a stainless pot in there is probably a waste of capacity. I have also had perfectly good results in converting it to a "virtual unvented pressure cooker" simply by putting the weight on the vent at 15 PSI, placing 3-4 quarters on top of the weight, keeping my eye on the pressure gauge and backing off the heat when the pressure hit 18 PSI or so over atmospheric.

The one way that you may have a real advantage is in knowing the actual temperature inside the cooker. When pressure canning, the only way of being sure of the temperature is to vent steam for 10 minutes or so that the entire interior is filled with water vapor and not air. If the pressure cooker is not vented, the temperature is certainly not as high as one might suppose it is.

--

Link to post
Share on other sites

good topic. I live at 5280 and have a pressure cooker that I check the temps with an IR thermometer and the only way I can get it up to 245, is to put a couple quarters on top of the pressure cap...works very well..

Bud

Link to post
Share on other sites

Interesting, but I wonder if all this is really necessary.

I have an WAFCO All-American pressure canner that is more or less the same thing you have, with a different top. Stocks don't strike be as acidic enough to particularly worry about the fact that it's made of aluminum, and none of the stocks I have made in there have suffered from metallic taste. So putting a stainless pot in there is probably a waste of capacity. I have also had perfectly good results in converting it to a "virtual unvented pressure cooker" simply by putting the weight on the vent at 15 PSI, placing 3-4 quarters on top of the weight, keeping my eye on the pressure gauge and backing off the heat when the pressure hit 18 PSI or so over atmospheric.

The one way that you may have a real advantage is in knowing the actual temperature inside the cooker. When pressure canning, the only way of being sure of the temperature is to vent steam for 10 minutes or so that the entire interior is filled with water vapor and not air. If the pressure cooker is not vented, the temperature is certainly not as high as one might suppose it is.

Interesting point that you make. I confess that I have a perhaps irrational bias against plain (non-nonstick) aluminum pots.

It's true that you can buy a different top for the All American Sterilizer that will convert it to a "regular" canner, if that's what you want. Even cheaper, I think you could replace the pressure regulator with more conventional jiggle weight.

What altitude are you working at?

Bob

Link to post
Share on other sites
Interesting point that you make. I confess that I have a perhaps irrational bias against plain (non-nonstick) aluminum pots.

It's true that you can buy a different top for the All American Sterilizer that will convert it to a "regular" canner, if that's what you want. Even cheaper, I think you could replace the pressure regulator with more conventional jiggle weight.

What altitude are you working at?

I'd probably be happier if it were lined with stainless or something like that (although I understand this would probably be impossible to do at this size and thickness of material). And I wouldn't cool tomato sauce in it or make a gigantic batch of gastrique.

I am in NYC, so compensating for altitude is not an issue. My procedure of putting quarters on the jiggle weight was entirely predicated on the idea of making the venting pressure canner (and pressure canners must be venting) into a non-venting pressure cooker for making stocks, based on the premise that stock quality is better when the cooker is non-venting.

--

Link to post
Share on other sites

The generally accepted rule for high-altitude pressure cooking is to increase the cooking time, and not the pressure.

In theory, it should give you the same results - because, after all, pressure shortens the cooking time by raising the cooking temperature so a lower temperature would require a longer cooking time.

I have not ACTUALLY tried this because I live at sea level on the shores of the Mediterranean Sea, but a few of my readers live in Colorado and have been able to pressure cook all kinds of recipes just by lengthening the cooking time.

Here are the instructions by Fagor...

"If you are cooking at high altitudes the cooking times must be longer, as water and cooking liquids come to a boil more slowly. A rule of thumb to remember is to increase the cooking time by 5% for every 1,000 feet above the first 2,000 feet ( 3,000 feet above sea level, add 5% to cooking time; 4,000 feet, add 10% ; and so on). Since the cooking times increase at altitudes higher than 2,000 feet, you will also have to add more cooking liquid to compensate. There are no fixed rules, so try increasing the cooking liquid by approximately half the percentage of the additional cooking time. For example, if the cooking time is increased by 10%, increase the cooking liquid by 5%."

http://www.fagoramerica.com/about_us/article_library/about_pressure_cooking#Pressure

Ciao!

L

hip pressure cooking - making pressure cooking hip, one recipe at a time!

Link to post
Share on other sites

LFMichaud said:

Interesting project! I would like to see pictures of your modifications of the lid. If I understand correctly with the 25psi relief valve we should be able to reach 130C at sea level.

Yes, according to the pressure gauge, 25 psi should equal 130C at sea level.

The only modification was to unscrew the pressure relief valve,and then screw it back into a T-adapter of the same thread type. Then I threaded two sensors through a brass cap that I had drilled out, filled it with epoxy, and screwed it onto the T.

I"m contemplating removing the pressure relief valve entirely and capping it, relying on the PID controller to keep things from getting too hot and blowing the secondary relief plug. But that would mean that I could no longer vent the hot air until it turns to steam, which is highly desirable for canning and the intended use for sterilization, although venting isn't recommended for making stock. Maybe I can find higher-pressure relief valve somewhere.

Link to post
Share on other sites
  • Similar Content

    • By eG Forums Host
      Modernist Cuisine at the eGullet Forums
      Here at eG Forums, we have what is probably the broadest collection of information on modernist cooking anywhere. We've discussed sous vide, the general chemistry of culinary modernism, practical applications with colloids and starches, and much, much more. A lot of this discussion is contained in our topics about the books Modernist Cuisine and Modernist Cuisine at Home (we have topics on both the books and on cooking with the recipes they present), but we've been modern since before modern was cool -- click on the 'Recent discussions tagged "Modernist"' link at the bottom of this page for a small sampling of what we've been up to. And feel free to use the Search tool at the top of the page to look for specific terms or people.

      Modernist Cuisine: The Art and Science of Cooking by Nathan Myhrvold with Chris Young and Maxime Bilet



      Support eG, buy the book at Amazon.com
      About the original book (Part 1, Part 2, Part 3)
      Cooking the recipes from the book (Part 1, Part 2, Part 3, Part 4)
      A Q&A with the Modernist Cuisine team

      Modernist Cuisine at Home by Nathan Myhrvold with Maxime Bilet



      Support eG, buy the book at Amazon.com
      About the book
      Cooking the recipes from the book (Part 1, Part 2)

      Other Modernist-related topics:
      Recent discussions tagged "Modernist"
      Sous Vide discussion index
    • By Porthos
      I picked up enough boneless short ribs to make 3 meals for my Sweetie and me. One meal will be pan-braised tonight. One has been vacuum-sealed and is in the freezer. My question is about seasoning, sealing, freezing, then defrosting and cooking at a later date. I'd like to season and seal the 3rd meal's worth. Can I use a dry rub on the meat, then seal, freeze, and cook at a later date? Does anyone else do this?
    • By newchef
      So I've now found myself at the water's edge of Modernist Cuisine.  Specifically, using sodium citrate for emulsifying all kinds of cheeses.  What I'm after is making an emulsified Parmesan sauce as well as another emulsified cheese sauce (most likely using Cheddar or Colby) that I can freeze and use later.  I'm a single guy and am no stranger of tweaking recipes for freezing but I haven't done it for modernist stuff yet.  I'd love to make a big batch of cheese sauce, freeze it into ice cubes for up to 3 months or so, and then take a few cubes out to thaw on a weeknight and toss with pasta, drizzle over veggies, etc.
       
      I looked at the modernist cuisine FAQ and saw this specific post about the cheese sauce that is "probably" freeze-able because it uses something called carageenan.  Has anyone been able to freeze sauce and keep it frozen for, say, a few months?  And not have to use carageenan?
       
      Thanks!
    • By WackGet
      Recently I picked up a few different types of emulsifiers in bulk powder form when I saw them in passing at a catering wholesaler.
       
      Having never used powdered emulsifiers before in cooking or baking, I figured I'd find pretty comprehensive instructions for their use on the web - but I can't.
       
      I'm not a stranger to food science but nor am I a chemist. I understand that emulsifiers are at least sometimes prepared by pre-mixing them into a (heated?) liquid or fat and then using the resulting solution in the actual recipe, which may explain why a lot of commercial emulsifier mixtures are packages as tubes of gel or paste. I've also checked several industry-level textbooks about emulsifiers and while they are fantastic for in-depth explanations of the chemistry behind each emulsifier, they do not (as you might imagine) provide guidance on how a lowly baker or cook would actually use a powdered form.
       
      So does anyone know how to prepare and use a dry powdered form of any of the following in a real recipe?
       
      Specifically I am most interested in enhancing baked goods and adding stability to sauces, but would also like to know how to use them for other processes such as sausage-making too.
      E471 Mono- and diglycerides of fatty acids E481 Sodium stearoyl lactylate E482 Calcium stearoyl lactylate E472e DATEM (diacetyl tartaric acid ester of mono- and diglycerides)
        Thanks.
    • By mjbarnard
      I cooked two turkey breasts sous vide. This year had access to the Meater+ thermometer probe which I managed to vacuum seal in the bag without difficulty (it is small). Since it works wirelessly I was able to monitor and it records the internal temperatures at the thickest part of the breast.
      I thought the results were interesting. I cooked at 60C for 8 hours. I have always used https://www.chefsteps.com/activities/a-better-way-to-turkey-cook-that-bird-sous-vide-for-the-best-feast-ever which gives long cooking times at lower temperature. I have found that as according to this page https://www.seriouseats.com/recipes/2014/11/sous-vide-turkey-breast-crispy-skin-recipe-thanksgiving.html that 55C gives turkey which is just a little too pink for most tastes. Over the last few years have increased the temperature up to 59/60 and I find it perfect - very moist and tender, but pale not pink.
      See attached images. I changed my mind a couple of times and started at 58 then 60 then 59 again, so ignore the slight variations. The thing I found interesting was that the thickest part (of a large breast) reached 55C in around 1 hour 40 mins and target of 59 in 2 hours 30 mins. Now I appreciate that sous vide is a combination of temperature and time or duration, but the data make me think that around 4 hours would be sufficient, as per the seriouseats table. I have previously used the chefsteps 55-58 for their much longer advised times, up to 12 hours and the meat is still quite pink at the end, so I dont believe 55 for 12 hours would effectively be the same.
      From now on I will watching the internal temperatures with interest. This has always been the (relative) unkown for sous vide amateurs. 


  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...