Canning

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The autoclaves operate differently than pressure canners. There is an inner container where the items to be sterilized are placed and they never touch the water. And there is an air purge tube going down into the bottom of the inner chamber to purge air. If you tried to pressure can with the autoclave, this purge tube would be underwater and cause water to spurt out of the top.

You might be able to rig it up for pressure canning (the first pressure canner was an autoclave at the MIT biology department) but it's just not set up for it.

Insert-air-exhaust-tube-into-channel.jpg

Although if the shit SHTF you could use a canner as an autoclave.
Just drop in a large pot and put the things you want to sterilise in the pot.
My Dad had an autoclave in the training room when he was the trainer for the Houston Rockets.
When they went on the road he'd pack all of his sterilized equipment in obviously sterilized packing.
He was going through the airport one trip and they insisted he open the sterilized packets so they could see what was in them when the x rays obviously showed hemostats and the like.
He raised bloody hell with security and they eventually gave in and let him go after a supervisor was called in.
 
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Here's what a dufus I am. My mother had given me a pressure cooker when I moved her down here on our property the end of February from Ky. She had so much stuff it kind of got tossed aside. My last post here I remembered she gave it to me and I put it away in the shed. I figured it was used with parts missing. I just went out and dug it out of all the stuff in shed. It's a small one...Presto 4 and 6 quart pressur cooker! Never been used and all parts were inside of it! I feel like I hit bonus jackpot!
 

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Here's what a dufus I am. My mother had given me a pressure cooker when I moved her down here on our property the end of February from Ky. She had so much stuff it kind of got tossed aside. My last post here I remembered she gave it to me and I put it away in the shed. I figured it was used with parts missing. I just went out and dug it out of all the stuff in shed. It's a small one...Presto 4 and 6 quart pressur cooker! Never been used and all parts were inside of it! I feel like I hit bonus jackpot!

Now you have two.
You could probably use it on pint jars to double your production.
 

DrHenley

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Although if the shit SHTF you could use a canner as an autoclave.
Just drop in a large pot and put the things you want to sterilise in the pot.
If you don't purge the air, the steam will not displace it in the inner chamber, and it will take a lot longer and a higher temperature. but you can do it. With pure steam (no air) you can sterilize at 273 °F for three minutes. With air in the inner chamber, it will take two hours at 320 °F.
 
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If you don't purge the air, the steam will not displace it in the inner chamber, and it will take a lot longer and a higher temperature. but you can do it. With pure steam (no air) you can sterilize at 273 °F for three minutes. With air in the inner chamber, it will take two hours at 320 °F.

I'd think it would work if you left the weight off longer than the required 10 minutes or even put the weight on and remove it periodically and used a pot only large enough to fit what you're trying to sterilize so the heat could better circulate.

Or you could go the old cowboy route and hold your stuff over the fire,although your bandages probably wouldnt fare well.🙂
 

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DrHenley

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There are other ways to purge the air. From Wikipedia:

Air removal
It is very important to ensure that all of the trapped air is removed from the autoclave before activation, as trapped air is a very poor medium for achieving sterility. Steam at 134 °C (273 °F) can achieve a desired level of sterility in three minutes, while achieving the same level of sterility in hot air requires that it spend two hours at 160 °C (320 °F). Methods of air removal include:

Downward displacement (or gravity-type)
As steam enters the chamber, it fills the upper areas first as it is less dense than air. This process compresses the air to the bottom, forcing it out through a drain which often contains a temperature sensor. Only when air evacuation is complete does the discharge stop. Flow is usually controlled by a steam trap or a solenoid valve, but bleed holes are sometimes used. As the steam and air mix, it is also possible to force out the mixture from locations in the chamber other than the bottom.

Steam pulsing
air dilution by using a series of steam pulses, in which the chamber is alternately pressurized and then depressurized to near atmospheric pressure.
Vacuum pumps
a vacuum pump sucks air or air/steam mixtures from the chamber.

Superatmospheric cycles
achieved with a vacuum pump. It starts with a vacuum followed by a steam pulse followed by a vacuum followed by a steam pulse. The number of pulses depends on the particular autoclave and cycle chosen.

Subatmospheric cycles
similar to the superatmospheric cycles, but chamber pressure never exceeds atmospheric pressure until they pressurize up to the sterilizing temperature.

Stovetop autoclaves used in poorer or non-medical settings do not always have automatic air removal programs. The operator is required to manually perform steam pulsing at certain pressures as indicated by the gauge.
 
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There are other ways to purge the air. From Wikipedia:

Air removal
It is very important to ensure that all of the trapped air is removed from the autoclave before activation, as trapped air is a very poor medium for achieving sterility. Steam at 134 °C (273 °F) can achieve a desired level of sterility in three minutes, while achieving the same level of sterility in hot air requires that it spend two hours at 160 °C (320 °F). Methods of air removal include:

Downward displacement (or gravity-type)
As steam enters the chamber, it fills the upper areas first as it is less dense than air. This process compresses the air to the bottom, forcing it out through a drain which often contains a temperature sensor. Only when air evacuation is complete does the discharge stop. Flow is usually controlled by a steam trap or a solenoid valve, but bleed holes are sometimes used. As the steam and air mix, it is also possible to force out the mixture from locations in the chamber other than the bottom.

Steam pulsing
air dilution by using a series of steam pulses, in which the chamber is alternately pressurized and then depressurized to near atmospheric pressure.
Vacuum pumps
a vacuum pump sucks air or air/steam mixtures from the chamber.

Superatmospheric cycles
achieved with a vacuum pump. It starts with a vacuum followed by a steam pulse followed by a vacuum followed by a steam pulse. The number of pulses depends on the particular autoclave and cycle chosen.

Subatmospheric cycles
similar to the superatmospheric cycles, but chamber pressure never exceeds atmospheric pressure until they pressurize up to the sterilizing temperature.

Stovetop autoclaves used in poorer or non-medical settings do not always have automatic air removal programs. The operator is required to manually perform steam pulsing at certain pressures as indicated by the gauge.

So you should be fine letting the steam out just like with canning.
You leave the weight off for 10 minutes which is done to make sure you have nothing but steam in the canner.
Place the weight back on for 10 minutes or so and remove it again to see if you have nothing but steam.
You can run the canner up to 15 psi at which point the steam reaches 247.7 degrees F. which should be fine if you extend the time you leave items in the canner.
Just like with food safety you can make sure your food is safe by extending the time it's held at a given temp. It's not necessary to bring it to a certain high temp as long as you extend the time.

In a SHTF situation without an autoclave you should still be safe.
 
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With canning, the steam is going up through the whole space mixing with the air and taking it out. With the autoclave, the steam is going around the inner container, not through it. Air is heavier than steam.

Then you should be able to put a well fitting container in the canner and just let the steam rise up through the top vent.
Kinda like in the pic you posted.
Unless I'm missing something.
 
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My pressure canner came in early! It was supposed to be here on the 27th..it was delivered Friday! I haven't even opened the box yet. I am getting a late start but today is the day! Will be my first time using a pressure canner. Gonna try potatoes to start with. Also, pulling out my dehydrator and think I will dehyrate some frozen vegetables. My big freezer needs room and the bags of veggies are taking up a lot.
 
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My pressure canner came in early! It was supposed to be here on the 27th..it was delivered Friday! I haven't even opened the box yet. I am getting a late start but today is the day! Will be my first time using a pressure canner. Gonna try potatoes to start with. Also, pulling out my dehydrator and think I will dehyrate some frozen vegetables. My big freezer needs room and the bags of veggies are taking up a lot.

Funny you say that.
Ours was supposed to show up next Wednesday and they moved it back to today as well.
Supposed to be here before 8:00 pm.
While it's cool to get it early I dont think I'll be canning at 9:00 pm on a Sunday.
 

GaRp58

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I just canned about 12 lbs of tomatoes today with some onions with them and got 4 quarts of good stuff in the pantry. Do not have a pressure canner, just have to can hot and then boil them under water for another hour and hope for the best and they are sterilised...
 

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I know this isn’t about canning, but hoping Ican get some feedback on Sun Ovens. All American makes a sun oven and I was wondering who has used them and kind of results they achieved?
A friend of ours uses a sun oven a lot. She loves it. I think she made it herself though. We have no shortage of sun here in the summer.
 

GaRp58

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A friend of ours uses a sun oven a lot. She loves it. I think she made it herself though. We have no shortage of sun here in the summer.
I have plans for a sun oven and know it can bake bread without a crust, the funny thing is, I also have plans for a solar distillator for making drinking water from the atmosphere and they both almost look the same. Black inside, wood outside, glass on top...just the distiller has a glass bottom also and a collector drain on the slanted bottom to let the drops collect, run into a rain gutter and down into a the water tank. Both are good alternatives for BOL and daily use. For those who are thinking about these and want a short look how the look, work and such:

 

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