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Pressure Finish on Roasts Using Lower Pressures?

thirdeye

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My pressure canner has a gauge and a weight and when I finish a big chuck roast, a brisket or finish several pastrami I use it instead of my smaller pressure cooker. These roasts are usually 160°ish and I'm using the pressure time mainly as a tenderization step, like wrapping or braising.

Is there any logic to using a lower pressure, say 8# instead of 12 or 13#, and processing a little longer? My pressure cookers have a fixed pressure, but with my gauge I can pick and hold about any pressure I want.
 

SecondHandSmoker

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Lower pressures mean longer times.
I have handed down recipes that all used 15# cookers at the time.
Since my IP Duo only goes up to 13#, I had to adapt the recipes to longer times.
Not sure if this answers your question or helps in any way.
 

thirdeye

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Lower pressures mean longer times.
I have handed down recipes that all used 15# cookers at the time.
Since my IP Duo only goes up to 13#, I had to adapt the recipes to longer times.
Not sure if this answers your question or helps in any way.
Not actually.... You're right that most pressure cooker recipes use 15#, but there are a number of cookers that are lower for a safety factor. The Miss Vicki site used to have a time conversion chart for adjusting recipes to certain brands.

But here is where I'm headed with my question.... A typical chuck roast pressure cooker recipe for example might call for browning the roast and then moving right into pressure cooking it based on 15# of pressure. I do more of a partial cook usually on my smoker, but sometimes oven roasted so I've got some bark formed and my internal temps are north of 160°. So these kind of meats are in my pressure cooker just long enough to tender up. My question better stated might be "Would I get a better product if I used 8# of pressure and just adjusted the time?" Or will something pressured at 15# result in the same mouthfeel? Sort of like my logic of smoking a pork butt at 240° for 15 hours is better than roasting it at 500° for maybe 3 hours.
 

SmokinEdge

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I have some temperature/weight values written down. So if you live where water boils on the stove top at 212* then that is the base line of “zero pressure “ then it goes like this:
5 psi = 220* F
10 psi= 235*F
15 psi= 250*F
 

SecondHandSmoker

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Not actually.... You're right that most pressure cooker recipes use 15#, but there are a number of cookers that are lower for a safety factor. The Miss Vicki site used to have a time conversion chart for adjusting recipes to certain brands.

But here is where I'm headed with my question.... A typical chuck roast pressure cooker recipe for example might call for browning the roast and then moving right into pressure cooking it based on 15# of pressure. I do more of a partial cook usually on my smoker, but sometimes oven roasted so I've got some bark formed and my internal temps are north of 160°. So these kind of meats are in my pressure cooker just long enough to tender up. My question better stated might be "Would I get a better product if I used 8# of pressure and just adjusted the time?" Or will something pressured at 15# result in the same mouthfeel? Sort of like my logic of smoking a pork butt at 240° for 15 hours is better than roasting it at 500° for maybe 3 hours.
I see where you're headed now.
Perhaps the only way to know is to do some experimenting.
 
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thirdeye

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I have some temperature/weight values written down. So if you live where water boils on the stove top at 212* then that is the base line of “zero pressure “ then it goes like this:
5 psi = 220* F
10 psi= 235*F
15 psi= 250*F
I'm at 5400' elevation so water boils at 203°. When canning I need 13 psi and I believe that gives me 240° inside the cooker. I took a stackable 15# weight and ground down a washer so now it jiggles at roughly 13.5 psi. Not a big deal when processing quarts or pints as they have default times. But I use a lot of 1/2 pint jars for fish (using the pint processing time), and 1.5 pint jars (using the quart processing times) for meats. I'm leaning toward over-processing anyway so I don't want to use 15#. That extra 2# for 90 minutes adds up.
 

SecondHandSmoker

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The Miss Vicki site
I haven't been to the Miss Vicki website in probably four or five years. I visited the site today and it seemed totally changed from what I remember or maybe it's just my CRS kicking in. 🤷‍♂️
 

SmokinEdge

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I'm at 5400' elevation so water boils at 203°. When canning I need 13 psi and I believe that gives me 240° inside the cooker. I took a stackable 15# weight and ground down a washer so now it jiggles at roughly 13.5 psi. Not a big deal when processing quarts or pints as they have default times. But I use a lot of 1/2 pint jars for fish (using the pint processing time), and 1.5 pint jars (using the quart processing times) for meats. I'm leaning toward over-processing anyway so I don't want to use 15#. That extra 2# for 90 minutes adds up.
Yes sir. I’m at 6450’ elevation. I too error to the high side. 15# all about temp over time. Botulism is the only concern in canning. Wondering why we can’t add a little nitrite first for botulism then can at lower pressure?
 

thirdeye

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Yes sir. I’m at 6450’ elevation. I too error to the high side. 15# all about temp over time. Botulism is the only concern in canning. Wondering why we can’t add a little nitrite first for botulism then can at lower pressure?
It's the same dilemma I face when using the 1/2 pint or 1.5 pint jars.... when the 'official' testing was done in the 30's and 40's they only used pints and quarts, so to be technically correct both of those sizes are processed at times for larger jars. So since nitrites were not included in the testing, there is no provision for them in the 'rules'.

For a while corned beef slipped by. I have an old Ball book with a recipe to corn beef and procedures to can corned beef (which I have done for many years).... then someone realized that 'cured' meats are not the same as fresh meats and no testing was done on cured meats. So Ball pulled both recipes before the next edition of the Blue Book. Canning smoked salmon falls into the same situation... canning fresh fish was okay, cured salmon was not okay. The state extension offices in Alaska and I think Washington (or Oregon) did their own testing on cured and smoked fish because so many folks were doing it. Their results determined more water was needed in the canner, and more time when processing.
 

daveomak

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Yes sir. I’m at 6450’ elevation. I too error to the high side. 15# all about temp over time. Botulism is the only concern in canning. Wondering why we can’t add a little nitrite first for botulism then can at lower pressure?

Nitrite kills botulism bacteria... From what I understand, it does not kill the spores....
Pressure canning at 240+ kills the spores....

Follow these pressure-canning steps to kill botulinum spores

Successful processing in a pressure canner requires attention to several details:


  • Vent pressure canners for 10 minutes at the start of processing. Venting drives air from the canner. If air remains trapped in the canner, the canner will not reach pressure or pressurization will take a long time. A poor, unsafe product will be the result.
  • Adjust for elevation. When pressure canning meats and vegetables, it is important to adjust processing pressure for elevation. The highest altitude in Minnesota is 2,000 feet.
    • Dial gauge, up to 2,000 ft. - 11 pounds pressure (11 psi).
    • Weighted gauge, up to 1,000 ft. - 10 pounds pressure (10 psi).
    • Weighted gauge, above 1,000 ft. - 15 pounds pressure (15 psi).
  • Keep an eye on pressure. Start counting processing time when the correct pressure is reached and regulate heat to maintain a steady pressure.
  • Bring the pressure back up and retime the entire process if at any time the pressure drops below the processing level. Fluctuating pressures can cause jars to lose liquid and damage seals or lead to under-processing and unsafe food.
  • Allow the canner to depressurize when the timed process is completed. Do not force-cool the canner.
  • Reprocess within 24 hours, if necessary. If jars fail to seal, remove the lid and check the jar-sealing surface for tiny nicks. If necessary, change the jar, add a new, properly prepared lid and reprocess within 24 hours using the same processing time. Otherwise, refrigerate the jars and use within 2-3 days or freeze the jars for later use.

botulism-symptoms-1x.jpg


Contents [Hide]
What is botulism?

The term “Botulism” is commonly used to describe poisoning with Clostridium botulinum toxin. Clostridium botulinum bacteria are normally found in soils and aquatic sediments. To thrive, the bacteria need:


  • Temperatures between 40-120°F/ 5-49°C
  • Anaerobic conditions (Oxygen below 2%)
  • Neutral pH
  • Moist conditions (Water activity level greater than 0.85)

A sealed jar of moist, low acid food provides excellent conditions for the growth of botulism bacteria. If food is not processed correctly, it's possible for the toxins to build to dangerous levels within 3-4 days.


Normally, botulism spores hang out and go right through your body without causing problems.


They're tough critters. Hours of boiling, heat, cold, chemicals – they can survive them all.


Problems show up when the spores germinate. When the spores become biologically active, they produce deadly neurotoxins.


Out in the dirt, no big deal. There are plenty of other microbes to balance things out, and the toxins don't build up to high levels. Stored in your canning pantry – not good.

How dangerous is botulism?

Botulinum toxin can kill you. (This goes for the C. botulinum used in Botox® treatments, too.)


If botulism symptoms are caught early, there is a botulism antitoxin that can prevent paralysis and death.

How can I get botulism?

The CDC monitors four different categories of botulism causes (transmission categories):


  • Foodborne botulism is caused by the consumption of foods containing pre-formed botulinum toxin.
  • Wound botulism is caused by toxin produced in a wound infected with Clostridium botulinum.
  • Infant botulism by definition occurs in persons less than one year of age and is caused by consumption of spores of C. botulinum, which then grow and release toxins in the intestines.
  • “Other” botulism: Consistent with the Council of State and Territorial Epidemiologists (CSTE) position statements, the “other” category includes botulism in which the route of transmission is unknown. Cases are classified as “other” if the patient with confirmed botulism is not an infant, has no history of ingesting a suspect food, and has no wounds. The “other” category also includes iatrogenic botulism, which is caused by an accidental overdose of botulinum toxin (that is, a therapeutic or cosmetic injection), and adult intestinal colonization (adult intestinal toxemia) botulism, a rare kind of botulism that occurs among adults by the same route as infant botulism.

Babies tend to pick up botulism spores because they crawl around on the ground where the spores are more abundant. It's also recommended that raw honey not be fed to infants under one year of age.


In 2015, the CDC Surveillance Network recorded the following:


A total of 199 confirmed and 14 probable cases of botulism were reported to CDC in 2015.
Among confirmed cases, infant botulism accounted for 141 (71%) cases, foodborne botulism for 39 (20%) cases, wound botulism for 15 (8%) cases, and botulism of unknown or other transmission category for 4 (2%) cases.
Among probable cases, foodborne botulism accounted for 6 (43%) cases and wound botulism for 8 (57%) cases.
How do I know if canned goods have botulism toxin in them?

You can't see or taste botulism spores or toxins until the toxins build up to excessive levels. This is one reason botulism is dangerous.


Lisa Rayner quotes a pressure canner booklet in her Natural Canning Resource Book, stating, “A rank cheesy odor is typical of botulism in its well-developed stage.”

Botulism Symptoms

If you think someone has botulism symptoms, call 911.


As mentioned above, it can kill.


Initial symptoms include nausea and vomiting. Neurological symptoms begin within 12-72 hours of eating contaminated food.


Symptoms of botulism include:


  • Blurred vision/double vision
  • Drooping Eyelids; other signs of facial nerve paralysis
  • Slurred speech
  • Nausea and vomiting
  • Difficulty swallowing, dry mouth and throat
  • Tachycardia
  • Respiratory paralysis
  • Constipation, problems urinating
  • Muscle weakness

You can't spread botulism person-to-person. The toxins must be ingested.

When Pressure Canned Food Goes Bad

One gentleman found out the hard way that canning shortcuts are not a good idea. The following is from the article “Home Canning Hobby Leads To Near Fatal Medical Mystery“:


Mike O'Connell “pressure canned” elk, but he cut the processing time and didn't follow correct canning practices. It nearly killed him.


“Borrowed a pressure cooker, used an old family recipe for canning,” O’Connell said.


O’Connell’s mother had canned everything when he was a kid. He wanted to recapture a bit of his childhood. But things started going wrong from the start.


I had way too much meat to deal with,” said O’Connell.


The pressure cooker was too small. O’Connell had already browned the meat in a cast iron pan. So he decided to shortcut the process. Once the jars sealed airtight he would take them out of the pressure cooker and start a new batch. The next day, he heard a pop in the pantry.


“Which I remember as a child was the signal for you’ve lost the seal,” said O’Connell.


O’Connell found the jar with the popped seal, put it in the fridge and ate it the next day. He says it was delicious. The following week he heard another lid pop. Just as he had before, O’Connell found the jar and stuck it in the fridge. And a few days later he ate it for supper.


“This time, it didn’t work out,” O’Connell said.


O’Connell had an upset stomach in the night, but he didn’t connect it to having eaten the meat. He says growing up, he didn’t know anyone who got food poisoning from home canned foods.

At the Hospital

At the hospital, once doctors ruled out a stroke, O’Connell was sent home. But he was back in the hospital a few hours later. Now he was having difficulty swallowing. The next morning, Mother’s Day, O’Connell’s daughter, Kelly Weisfield, drove to Olympia to see her dad.


“His voice was very slurred and his eyelids were droopy, but he was sitting up in bed and he was communicative,” Weisfield said.


As the day progressed though, O’Connell’s condition got markedly worse.


“By now, my eyes were closed. My strength—it was just amazing how quickly that went,” O’Connell said.


His breathing was getting shallow. Daughter Weisfield was frustrated with the lack of answers and scared. She called a doctor she knew, a neurosurgeon. He ran through a short checklist of things to rule out. That list included a disease first identified in the 18th century: botulism. Weisfield looked it up online.


“It just made the hair on the back of my neck stand up because it was every single symptom just laid out exactly what my dad was experiencing,” she said.

A Potent Toxin

Botulism is a paralyzing illness caused by what Centers for Disease Control calls the most potent toxin known to science. It’s rare; there were only 20 foodborne cases nationwide in 2011, just one in Washington state last year.


Improperly home canned foods are the leading culprit, especially those low in acid like green beans and, yes, meats. Weisfield called her mom who had just left the hospital.


“And I said, ‘Mom, turn around. You got to go back and tell them to look into this,’” Weisfield said.


Weisfield was relieved, but also terrified that it was too late. Her father could hardly move now. He was having more and more difficulty breathing. The hospital had parked a ventilator outside his room. Weisfield didn’t know what to tell her 10-year-old son, who is very close to his grandfather.


“First thing Connor said was, ‘Are we still going to go on our fishing trip?’ And I could never answer him, because I didn’t know,” she said.


The doctors didn’t even wait to confirm botulism. They ordered a dose of anti-toxin from the CDC. Now the medical mystery was solved. But how did O’Connell get botulism?


Remember he stopped cooking the jars of elk meat when he heard the seals lock in place. Washington State University food safety expert Zena Edwards says that was O’Connell’s nearly fatal mistake.


“All that indicated was it had now become an anaerobic environment, an oxygen-free environment,” Edwards said.


And that’s the strange thing about the bacteria that causes botulism. It thrives when deprived of oxygen. By shortcutting the cooking time, O’Connell failed to kill the bacteria. Instead, he sealed it into the perfect environment for it to produce the poisonous toxin.


avoiding-botulism-in-canning-wide18-1024x683.jpg

How to Prevent Botulism in Home Canned Foods

To prevent botulism poisoning, you need to avoid the conditions that cause the spores to germinate and/or kill off the spores.


Keep spores from germinating by:


  • Having a pH ≤ 4.6 (High acid foods)
  • Adding sugar or salt to tie up free water (High sugar jams, pickled foods with salt and vinegar)

Kill botulism spores using a pressure canner and tested canning recipes.


Spores are destroyed by heating food to 240-250°F/116-121°C under pressure of 10-15 pounds per square inch (psi) at sea level.



Adjustments are required for elevation. Increase processing time for water bath canning and processing pressure for steam canning.


Safe processing allows all the food in the jars to reach the required temperature and pressure.


For extra safety, boil low acid foods for 10 minutes before serving. (See The Natural Canning Resource Book for more information.)


The Ball Blue Book has an altitude adjustment chart, as would a new pressure canner.

Botulism Treatment

If someone still manages to get sick, get them to the hospital immediately. Do not attempt home treatment. They must get the botulism antitoxin.
 

daveomak

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Lower pressures mean longer times.
I have handed down recipes that all used 15# cookers at the time.
Since my IP Duo only goes up to 13#, I had to adapt the recipes to longer times.
Not sure if this answers your question or helps in any way.
Your IP Duo does NOT have USDA approval to pressure can all kinds of foods...
 

SecondHandSmoker

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Your IP Duo does NOT have USDA approval to pressure can all kinds of foods...

Yes Dave, that is correct. Since can only produce 12-13#'s on the high setting it is not recommended/approved for pressure canning.
Even if it could produce 15#, it's too damn small for large batch canning.

I should have clarified, about what I meant about adapting old recipes that used 15# stove top cookers over to the IP Duo...you know recipes like Swiss Steak, etc.
 
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thirdeye

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Lower pressures mean longer times.
I have handed down recipes that all used 15# cookers at the time.
Since my IP Duo only goes up to 13#, I had to adapt the recipes to longer times.
Not sure if this answers your question or helps in any way.
Your IP Duo does NOT have USDA approval to pressure can all kinds of foods...
I've been jumping back and forth between pressure cooking and pressure canning. In this context I believe we were visiting about pressure cooking recipes (which are mostly based on 15#) and newer pressure cookers that are set at 13#.... meaning a change in time is needed.

But, it's always good to point out that pressure cookers can't be used for pressure canning.
 

SecondHandSmoker

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I've been jumping back and forth between pressure cooking and pressure canning. In this context I believe we were visiting about pressure cooking recipes (which are mostly based on 15#) and newer pressure cookers that are set at 13#.... meaning a change in time is needed.

But, it's always good to point out that pressure cookers can't be used for pressure canning.

Correct.
 

SecondHandSmoker

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I've been jumping back and forth between pressure cooking and pressure canning. In this context I believe we were visiting about pressure cooking recipes (which are mostly based on 15#) and newer pressure cookers that are set at 13#.... meaning a change in time is needed.

But, it's always good to point out that pressure cookers can't be used for pressure canning.

Plus, we we discussing if it is feasable/possible to use a pressure canner for finishing roasts etc.
I am not sure if they are still available, but I believe there is a pressure smoker some company was advertising...
 

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