All grain canned wort, so far so good!

[Broothru]

Wow - mine has a 12,000 BTU limit!

Whoops, you're right !

The main burner of my grill is 35,000 BTU, not the side burner which is 10,000 BTU. And you are correct: the maximum INPUT heat for the Presto pressure canner is 12,000 BTU.

Please don't make me the BUTT of any "age-related" jokes.

Brooo Brother

 

[Dave Sarber]

Well, I've always just used mine on the stove, but that's a good warning. Just got a new Gas One burner that puts out 200,000 btu. I guess it would melt my canner if I tried it.

 

[RocketBrewer]

I use mine all the time on my turkey fryer propane jet burner, which I believe is rated at 55K BTU. That is a maximum rating, I just keep it turned way down and heat it slowly. You should always pay very close attention when using a pressure cooker, bad things can happen if you don't.

 

[Dog House Brew]

I can a lot from the garden. I. Bought a 941 All American and use the brewery burner. It holds 19 quarts. The time is elevation dependent I believe. I think I did mine 15# for 20min. I like to use it for waking up older yeast. I did some at .020 and some at .040.

 

[Broothru]

I can a lot from the garden. I. Ought a 941 All American and use the brewery burner. I holds 19 quarts. The time is elevation dependent I believe. I think I did mine 15# for 20min. I like to use it for waking up older yeast. I did some at .020 and some at .040.

It's actually time and pressure. The thing about altitude has to do with the temperature at which water boils with decreasing atmospheric pressure. Sea level standard pressure (~1013 millibars), pure water boils at 212F/100C. That boiling temperature goes down as your elevation goes up and the weight of a theoretical column of air goes down. In Denver (Mile High) water boils at 203F/95C. Conversely the boiling temperature of water goes up as pressure increases (as in a pressure cooker). That 15 lb. "equivalent" weight that rattles around on your pressure cooker has the effect of "raising" the pressure in your cooker by approximately 15 psi, thus raising the temperature at which water boils. In this case the boil point is raised to about 250F.

The objective here is to kill botulism spores that can multiply anaerobically in your Mason jar of wort and poison you. The temperature must reach around 250F for about 15 minutes to eliminate the nasties. So if you bath the jars in 250F for a sufficient period of time, mission accomplished. If you're pressure canning in Denver, you likely won't reach 250F water temperature in the pressure canner. No matter how much heat you apply to the outside of the canner, the water temperature will never exceed the boiling temperature of the water at your local atmospheric pressure. On the other hand, the temperature of the steam venting from the PRV on the canner is the difference between the inputted temperature from your 35,000 BTU burner and the boiling temperature of the water.

If you're cranking out 900F from your heat source and the boiling point of the water is 212F, the temperature of the steam is roughly 900F - 212F = 688F ('roughly', because there are losses due to latent heat of vaporization as well as absorption of heat energy by the canner itself, just to mention a few). So if you're pressure canning in Denver on a stormy day when the barometric pressure may only be 995 mb, the botulism spores will likely survive, and you may not.

Brooo Brother

 

[Dog House Brew]

Nice info, I’m glad I’m not at elevation. I never thought about what does to someone trying to can at elevation. I read somewhere 15, and again read 20min. So I canned them for 20min@15#.

 

[marc1]

It's actually time and pressure. The thing about altitude has to do with the temperature at which water boils with decreasing atmospheric pressure. Sea level standard pressure (~1013 millibars), pure water boils at 212F/100C. That boiling temperature goes down as your elevation goes up and the weight of a theoretical column of air goes down. In Denver (Mile High) water boils at 203F/95C. Conversely the boiling temperature of water goes up as pressure increases (as in a pressure cooker). That 15 lb. "equivalent" weight that rattles around on your pressure cooker has the effect of "raising" the pressure in your cooker by approximately 15 psi, thus raising the temperature at which water boils. In this case the boil point is raised to about 245F.

The objective here is to kill botulism spores that can multiply anaerobically in your Mason jar of wort and poison you. The temperature must reach around 240F for about 15 minutes to eliminate the nasties. So if you bath the jars in 245F for a sufficient period of time, mission accomplished. If you're pressure canning in Denver, you likely won't reach 245F water temperature in the pressure canner. No matter how much heat you apply to the outside of the canner, the water temperature will never exceed the boiling temperature of the water at your local atmospheric pressure. On the other hand, the temperature of the steam venting from the PRV on the canner is the difference between the inputted temperature from your 35,000 BTU burner and the boiling temperature of the water.

If you're cranking out 900F from your heat source and the boiling point of the water is 212F, the temperature of the steam is roughly 900F - 212F = 688F ('roughly', because there are losses due to latent heat of vaporization as well as absorption of heat energy by the canner itself, just to mention a few). So if you're pressure canning in Denver on a stormy day when the barometric pressure may only be 995 mb, the botulism spores will likely survive, and you may not.

Brooo Brother

I'm not at altitude, so this doesn't apply to me, but the pressure canner directions that I have specify more stringent processing for pressure canning at altitude.
It does not give an altitude at which you cannot pressure can, just 15lbs pressure instead of 10.

Altitude Adjustment
The processing times given in the specific meat, poultry, fish, and soup recipes are for altitudes of 1,000 feet or less. When pressure canning above 1,000 feet, process at 15 pounds of pressure. Processing time is the same at all altitudes.

 

[marc1]

Nice info, I’m glad I’m not at elevation. I never thought about what does to someone trying to can at elevation. I read somewhere 15, and again read 20min. So I canned them for 20min@15#.

I don't think that there are any officially tested "safe" recipes for canning wort. I couldn't find any - if anyone does please post them with the reference!
I estimated that wort would have a consistency similar to beef and chicken stock, so I based my canning times off of that. The manual that I have recommends beef and chicken stock be canned at 10 pounds of pressure, 20 minutes for pints and 25 minutes for quarts. I can quart jars of wort and wanted to build in an extra margin of safety, so I do 15 pounds of pressure for 30 minutes.

 

[Broothru]

I don't think that there are any officially tested "safe" relcipes for canning wort. I couldn't find any - if anyone does please post them with the reference!
I estimated that wort would have a consistency similar to beef and chicken stock, so I based my canning times off of that. The manual that I have recommends beef and chicken stock be canned at 10 pounds of pressure, 20 minutes for pints and 25 minutes for quarts. I can quart jars of wort and wanted to build in an extra margin of safety, so I do 15 pounds of pressure for 30 minutes.

That's OK to go longer, but the concern is still time and temperature. If you used a basic non-pressure canner with boiling water (212F) you would never reach the temperature threshold for destroying the spores. Here's a summary from the University of California, Davis:

1. Do botulism bacteria die at boiling?

The bacterium Clostridium botulinum has two forms. The active form is also known as a vegetative form and the dormant form is called the spore form. Vegetative cells are much easier to destroy. Destruction is usually measured by a combination of TIME and TEMPERATURE – the hotter the temperature the shorter the time required to kill a given number of bacteria. There are many types of C. botulinum and they can vary in their heat sensitivity. But if all particles of food have reached boiling temperature (212F) then it would be reasonable to assume the vegetative cells of C. botulinum have been destroyed. The spores, however, would survive.

2. Do botulism spores die at 250F?

Killing spores is a time and temperature relationship and it is also heavily influenced by the properties of the food. This is why we do not have one process that is applicable to all low acid foods.


So to summarize, you can kill the 'vegetative' by cooking at a temperature less than 250F, but then you haven't killed the spores that produce the toxin. Also, I see that I improperly stated that the spores would be denatured at 245F instead of 250F. I'll edit my previous post to reflect that fact. And since:

"This is why we do not have one process that is applicable to all low acid foods..."

...your notion of extending the boil as an extra measure of safety is probably a wise decision.

Brooo Brother

 

[hottpeper13]

So Brooo, if I'm understanding you correctly you're saying that if i were to use my pressure caner at a Denver home game tailgating it won't get to 15 psi? I believe if you clamp a vessel down and add heat it will get to what ever the prv is set to regardless of elevation. i guess you can't have a cannery in the mountains.

 

[Broothru]

No, you'll get 15 psi just find, but you won't get 250F water from the boiling liquid.

 

[Dr_Jeff]

Lol, let the record show that my wife LOVES hers, and my great grandmother probably loved her analog analog instant pot version.
Also it should be noted that it’s not the only meals round here that I think is meh. Obviously it’s a me problem....

Complain enough about the meals, and she'll "let" you do the cooking.

 

[501irishred]

Complain enough about the meals, and she'll "let" you do the cooking.

True words sir. True words.....

 

[Broothru]

So Brooo, if I'm understanding you correctly you're saying that if i were to use my pressure caner at a Denver home game tailgating it won't get to 15 psi? I believe if you clamp a vessel down and add heat it will get to what ever the prv is set to regardless of elevation. i guess you can't have a cannery in the mountains.

Think of it this way, considering all the factors. Water doesn’t boil at 15 psi. It boils at 212F at sea level pressure. At less than sea level pressure (Denver partial atmospheric pressure) it boils as 203F. Same water, just less atmospheric pressure being exerted upon it. Take that same water to the bottom of Death Valley or beside the Dead Sea and it will not boil until something slightly higher than 212F. What we’re considering is not only the temperature but also the total atmospheric force caused by the weight of the atmosphere acting upon the water, and how it alters the boiling temperature of that water. It doesn’t matter whether it’s inside or outside the pressure vessel. Looked at from a different perspective, if you took a pot of 32.1F water, put it in the pressure lock of the International Space Station and suddenly exposed it to zero total atmospheric pressure it would boil (vaporize; phase change from liquid to gas) almost instantaneously. At 32.1F.


In the case of a pressure cooker we are artificially increasing the “local” pressure (be it Denver, Death Valley of Miami Beach) by ‘some amount’. The 15 lb equivalent weight we use increases the ‘local weight’ of the atmospheric pressure differential inside the pressure vessel with that actually present in the ambient atmosphere outside the pressure vessel. To determine what the total pressure is inside the pressure vessel you need to add the the increased pressure inside the vessel to the local ambient atmospheric pressure to get total pressure. It is total pressure that determines the temperature at which water boils.


Remember, the objective is to have the water temperature inside the cooker to get up to 250F to kill the botulism spores. By capping the cooker with ‘some amount’ of weight, you’ll increase the boiling temperature of water by ‘some amount’ because you increased the total pressure inside the cooker by ‘some amount’. At sea level, ‘that amount’ of pressure increase is enough to raise the boiling point of water to 250F. It just so happens that the 15 lb equivalent weight is the right amount of weight to raise the total pressure inside the cooker to that amount of pressure. The local pressure in Denver plus the artificially increased “15 lb. weight” is not sufficient to raise the boiling temperature of water to 250F.

Brooo Brother

 

[Nate R]

Ok... this is a LOT of math.
This reminds me chemistry 01 or 1A in my 1st year @ college. (Don't get me started on how everybody says 101 when they mean entry level! 101 is the beggining of the advanced classea! 01 or 1A is usually the entry level freshman class!). Ugh

Ok, rant aside- the chem teacher used a kickazz old school looking belt driven vacumn machine, with a hose that was like 3-6" thick, to create a vacumn/ pressure inside a very thick clear dome. Inside the dome was a container of water. He was able to get the water to boil!

I assume this is what he was demo strating? Water under enough pressure will boil?

Sure wish i had paid more attention...

Edit- grammer, and this is a you tube link.
Darn celcious and he does not show the machine or hose... the best parts!!

 

[501irishred]

Ok... this is a LOT of math.
This reminds me chemistry 01 or 1A in my 1st year @ college. (Don't get me started on how everybody says 101 when they mean entry level! 101 is the beggining of the advanced classea! 01 or 1A is usually the entry level freshman class!). Ugh

Ok, rant aside- the chem teacher used a kickazz old school looking belt driven vacumn machine, with a hose that was like 3-6" thick, to create a vacumn/ pressure inside a very thick clear dome. Inside the dome was a container of water. He was able to get the water to boil!

I assume this is what he was demo strating? Water under enough pressure will boil?

Sure wish i had paid more attention...

Edit- grammer, and this is a you tube link.
Darn celcious and he does not show the machine or hose... the best parts!!

This is the opposite of what takes place in a pressure canner obviously, but it is a great demonstration of the relationship between pressure and temperature to boil water. It also sounds like you should work refrigeration with me. I "get" to use a vacuum pump like this nearly everyday! I'd even "let" you watch the micron gauge for me!

 

[Nate R]

This is the opposite of what takes place in a pressure canner obviously, but it is a great demonstration of the relationship between pressure and temperature to boil water. It also sounds like you should work refrigeration with me. I "get" to use a vacuum pump like this nearly everyday! I'd even "let" you watch the micron gauge for me!

Ha- you would do that for me???
As this was a little community college, and it was 1999 or so, i think the equipment was from the 60's, give or take a decade.
And i bet it is still there, too!!!
They just don't make stuff like they used too for sure!

 

[GrowleyMonster]

A Presto 23 qt pressure canner is a lot cheaper, and holds more!

I have two of them. One with a gauge, one without. VERY versatile! Can. Cook. I even use it for a rice cooker, using the pot in a pot method. Absolutely perfect rice, way better than any rice cooker can manage. I pressure cook my ham hocks or neck bones for 45 minutes, cool, and remove the bones, and use the meat in my beans or my collard greens. Chuck roasts are divine. And yeah, I can, sometimes. A couple years ago we were growing jalapeños about 10x faster than I could use them, so I canned some seeded, some whole, and made salsa with some. Only just now have I ran out.

The problem with the electric ones is they are too darn smart. You can't see the underlying algorithms of the presets, and it is difficult to figure out how to use them manually. With my big presto, I light the fire and it gets hot. I turn it down and it gets just "so" hot. I turn it up and it goes bananas. I turn it off and it gradually cools. I know what it is doing by how the weight jiggles. No timers, no "soup" mode or "roast" mode or "chicken pot pie" mode or whatever. I make it do exactly what I want it to do.