Tomatoville® Gardening Forums


Notices

Information and discussion about canning and dehydrating tomatoes and other garden vegetables and fruits. DISCLAIMER: SOME RECIPES MAY NOT COMPLY WITH CURRENT FOOD SAFETY GUIDELINES - FOLLOW AT YOUR OWN RISK

Reply
 
Thread Tools Display Modes
Old August 17, 2015   #16
bitterwort
Tomatovillian™
 
Join Date: Feb 2006
Location: MN Zone4b
Posts: 292
Default

Worth, I have the Presto 23-quart canner and at the advice of a number of posters on the GW Harvest forum use it at as weighted-gauge plus dial gauge canner through the addition of a pressure regulator that has rings for 5, 10, and 15 psi.

Mine looks like this (but it cost considerably less--look around a bit):

http://www.amazon.ca/Presto-Pressure...JJT84YF082VMCD
__________________
Bitterwort
bitterwort is offline   Reply With Quote
Old August 17, 2015   #17
coronabarb
Tomatoville® Recipe Keeper
 
coronabarb's Avatar
 
Join Date: Jan 2006
Location: Roseburg, Oregon - zone 7
Posts: 2,821
Default

bitterwort, yes that's what I have and I think they are even cheaper here at our local farm supply store. I was discussing pressure canners with someone on a facebook canning group and she had a mirro I think it was? It only had weights, no gauge. I'd rather have the gauge as well as the weights so I can know when the pressure comes down to zero before opening the lid. I know the little button goes down when it is ready, but I still like to see it at 0.
__________________
Corona~Barb
Now an Oregon gal
coronabarb is offline   Reply With Quote
Old August 17, 2015   #18
coronabarb
Tomatoville® Recipe Keeper
 
coronabarb's Avatar
 
Join Date: Jan 2006
Location: Roseburg, Oregon - zone 7
Posts: 2,821
Default

This is why you shouldn't guess at processing times or think one size fits all. There are many factors that go into determining how to safely can foods. This is an explanation by an expert in Australia;

The timing given for any particular recipe is based on how long it takes for the entire contents of the jar to be heated to the safe temperature (240F - 250F) all the way through, and then it has to stay there for long enough to sterilise it. When they are testing recipes, they put little testing thermocouples in the jars that show the testers how fast the jars heat, whether it's even, and even how the heat moves through the food. Some ingredients are only recommended to be cut in particular ways because the size and shape of the pieces affects how fast and well they heat.

Some foods are dense - meaning they contain less water and air than other foods the same size, and they take longer to heat through and need longer processing. The ratio of solids to liquids can affect the rate of heating. Heat transfers more easily and quickly through liquid than through solids and dense mixtures, so a new canning process time would have to be determined through product testing if you were to increase the solid to liquid ratio.

Some foods have higher risk of spoilage because they naturally carry more fungi or bacteria on their skins. These also need longer processing times. And once they work out the minimum processing time needed to make a food safe for storage, then they also have to figure out the maximum time that you can process it without the food losing quality, either in texture and palatability, or in loss of vitamins and nutrition. The final times are based between those two to allow for variations in preparation and in the produce itself, and are designed to give home canners the best possible results in the safest but also the easiest way.

More details and explanation here;
http://nchfp.uga.edu/how/general/ens...ned_foods.html
__________________
Corona~Barb
Now an Oregon gal
coronabarb is offline   Reply With Quote
Old August 17, 2015   #19
Durgan
Tomatovillian™
 
Join Date: Feb 2013
Location: Brantford, ON, Canada
Posts: 1,341
Default

Quote:
Originally Posted by coronabarb View Post
This is why you shouldn't guess at processing times or think one size fits all. There are many factors that go into determining how to safely can foods. This is an explanation by an expert in Australia;

The timing given for any particular recipe is based on how long it takes for the entire contents of the jar to be heated to the safe temperature (240F - 250F) all the way through, and then it has to stay there for long enough to sterilise it. When they are testing recipes, they put little testing thermocouples in the jars that show the testers how fast the jars heat, whether it's even, and even how the heat moves through the food. Some ingredients are only recommended to be cut in particular ways because the size and shape of the pieces affects how fast and well they heat.

Some foods are dense - meaning they contain less water and air than other foods the same size, and they take longer to heat through and need longer processing. The ratio of solids to liquids can affect the rate of heating. Heat transfers more easily and quickly through liquid than through solids and dense mixtures, so a new canning process time would have to be determined through product testing if you were to increase the solid to liquid ratio.

Some foods have higher risk of spoilage because they naturally carry more fungi or bacteria on their skins. These also need longer processing times. And once they work out the minimum processing time needed to make a food safe for storage, then they also have to figure out the maximum time that you can process it without the food losing quality, either in texture and palatability, or in loss of vitamins and nutrition. The final times are based between those two to allow for variations in preparation and in the produce itself, and are designed to give home canners the best possible results in the safest but also the easiest way.

More details and explanation here;
http://nchfp.uga.edu/how/general/ens...ned_foods.html
There is a lot of assumptions, guess work if you like, in these recommendations. There are temperature sensing indicators available or that could be slightly modified for home canning that are not being used. It is time this area was re-addressed. In the meantime, my 15 minutes at 15 PSI on a slurry which means homogeneous material seems as logical and practical as any of the plagiarized findings produced on the internet.
Durgan is offline   Reply With Quote
Old August 17, 2015   #20
Nematode
Tomatovillian™
 
Join Date: May 2012
Location: massachusetts
Posts: 1,710
Default

I have the all american.
I can tell you like quality stuff.
You will like it too, and whoever gets it when you are gone, built like a tank.
Nematode is offline   Reply With Quote
Old August 17, 2015   #21
coronabarb
Tomatoville® Recipe Keeper
 
coronabarb's Avatar
 
Join Date: Jan 2006
Location: Roseburg, Oregon - zone 7
Posts: 2,821
Default

And therein lies the truth, Durgan. Your method 'seems' logical to you (practical has less importance than scientific research?). Science proves you incorrect. What seems logical to you does not stack up against scientists who have years of training and experience in a laboratory. When you said 85 mins pressure canning corn would result in mush, it is not true in the real world. I know many people who do just that every summer with the great results that a reasonable person would expect from guidelines reached through testing that takes months.

I used Naomi's correspondence to me as an illustration on how testing works. She included part of NCHFP's info on the ratio of solids to liquids and the effect of changing it to make a point. There are no assumptions, no guess work, just scientists working in labs using actual science to determine how to safely and effectively can w/o destroying the food. They have spent much $$ doing so. Saying it needs to be readdressed is folly.

You are the reason we have the disclaimer at the top. You are welcome to can anyway you like. But don't tell the rest of us that the NCHFP/USDA has it wrong because science proves you wrong. And that's the last word on this.
__________________
Corona~Barb
Now an Oregon gal
coronabarb is offline   Reply With Quote
Old August 17, 2015   #22
TomNJ
Tomatovillian™
 
TomNJ's Avatar
 
Join Date: May 2009
Location: Floyd VA
Posts: 771
Default

Quote:
Originally Posted by Durgan View Post
The bacterium Clostridium botulinum is completely annihilated at a temperature of 250F or 121C. This is achieved at a presure of 15 PSI. Any pressure lower does not achieve the necessary temperature. All pressure canning should be done at 15 PSI.

Pressure canning at lower pressures are decidedly wrong and put the public at risk.
This is just not true. Botulism spores can be killed at lower temperatures, it just takes longer. I read one study which showed the spores were killed at boiling temperature (212F) but it took 20 hours of boiling. At 10 psi (240F) the spores were killed in about 12 minutes, and at 15 psi (250F) they were killed in 2.5 minutes. These times were for spores inoculated in neutral water, and the kill time is less in an acidic medium.

As Coronabarb said, the actual time for a given recipe depends on the rate of full heat penetration which is a function of many factors, such as density, viscosity, chunk size, etc. This can be difficult to predict using rules of thumb. While most people do can their own recipes, it is safer to follow proven recipes such as those given by the NCHFP, at least for low acid foods.

TomNJ/VA
TomNJ is offline   Reply With Quote
Old August 17, 2015   #23
TomNJ
Tomatovillian™
 
TomNJ's Avatar
 
Join Date: May 2009
Location: Floyd VA
Posts: 771
Default

Worth, I bought a 30 quart All American pressure canner nine years ago and absolutely love it. It is expensive and heavy, but built like a tank and will last your lifetime and that of your children and grandchildren as well. It doesn't need any gaskets and has a gauge and weight. I paid $240 for mine, but amortized over 20 years of canning it will cost only $12/year.

The 30 quart version will hold 19 pints jars or 14 quart jars (double stacked). I need this capacity for my canning needs, and along with the Victorio mill it makes canning a pleasure. I put up 87 pints of salsa in the past two weeks, and will start on tomato sauce this week.

TomNJ/VA
TomNJ is offline   Reply With Quote
Old August 17, 2015   #24
AlittleSalt
BANNED FOR LIFE
 
AlittleSalt's Avatar
 
Join Date: May 2014
Posts: 13,333
Default

I have the 23 quart Presto Pressure Canner. I have no idea how to use it, but will use proven recipes when it is time to use it.

I guess getting a PHD of Culinary Arts would help.

But seriously, I had no idea sea level meant anything with using a pressure canner.
AlittleSalt is offline   Reply With Quote
Old August 17, 2015   #25
Worth1
Tomatovillian™
 
Worth1's Avatar
 
Join Date: Feb 2006
Location: Den of Drunken Fools
Posts: 38,539
Default

Quote:
Originally Posted by Nematode View Post
I have the all american.
I can tell you like quality stuff.
You will like it too, and whoever gets it when you are gone, built like a tank.
I'm thinking about getting the 30 quart one so I can, process 14 quarts at one time.

Now I have came to another realization.
I am so glad I have taken my time buying a canner.
The main reason I was thinking about the Presto is I can use it in the glass top stove.
My stove says I can the the presto site says I can if the stove says I can.
(Yes my stove talks to me).
All American says not to because of the weight but they say that on their smallest canner.
The other thing is the indentation on the bottom of the canner they say or I read somewhere could cause a vacuum on the stove.
All of my large kettles and post have this same indentation and I have never had a vacuum.

Well anyway the deciding factor was something that was staring me in the face all along.
I feel like an idiot for not seeing it before.

My Microwave is mounted above the stove no matter which canner I get I will have to get a separate burner for the canner.
Neither one of the bigger canners will fit under the microwave.
The presto might maybe.
If any of you would like to could you measure your All American 25 or 30 quart or 23 quart Presto at the edge and say what it is.
So the 30 quart All American it is, I think.
For small batches I still have my little canner that will can 4 quarts.

Worth
Worth1 is offline   Reply With Quote
Old August 17, 2015   #26
Worth1
Tomatovillian™
 
Worth1's Avatar
 
Join Date: Feb 2006
Location: Den of Drunken Fools
Posts: 38,539
Default

Quote:
Originally Posted by AlittleSalt View Post
I have the 23 quart Presto Pressure Canner. I have no idea how to use it, but will use proven recipes when it is time to use it.

I guess getting a PHD of Culinary Arts would help.

But seriously, I had no idea sea level meant anything with using a pressure canner.
Salt this is why I cant watch some of the space movies, the things that go on in them break all the laws of physics.
Try as they may I still catch something.

And yes a gun would fire in outer space the propellant has everything it needs.
But in the extreme cold on the dark side of the moon it would shatter at -280F.

Worth
Worth1 is offline   Reply With Quote
Old August 17, 2015   #27
Worth1
Tomatovillian™
 
Worth1's Avatar
 
Join Date: Feb 2006
Location: Den of Drunken Fools
Posts: 38,539
Default

Quote:
Originally Posted by TomNJ View Post
Worth, I bought a 30 quart All American pressure canner nine years ago and absolutely love it. It is expensive and heavy, but built like a tank and will last your lifetime and that of your children and grandchildren as well. It doesn't need any gaskets and has a gauge and weight. I paid $240 for mine, but amortized over 20 years of canning it will cost only $12/year.

The 30 quart version will hold 19 pints jars or 14 quart jars (double stacked). I need this capacity for my canning needs, and along with the Victorio mill it makes canning a pleasure. I put up 87 pints of salsa in the past two weeks, and will start on tomato sauce this week.

TomNJ/VA
Tom did the 30 quart come with an extra rack to stack the jars?
Not that it matters I could make one.
Worth
Worth1 is offline   Reply With Quote
Old August 17, 2015   #28
coronabarb
Tomatoville® Recipe Keeper
 
coronabarb's Avatar
 
Join Date: Jan 2006
Location: Roseburg, Oregon - zone 7
Posts: 2,821
Default

Worth YES! I remember hearing this and was thankful I had no microwave above the stove. I have the 23 qt Presto and haven't used it on my glass stove yet. Kind of hesitant even though my stove model says it is okay. I would love to have the heavy duty All American but I'm quite sure I could not lift it, esp when full.
__________________
Corona~Barb
Now an Oregon gal
coronabarb is offline   Reply With Quote
Old August 17, 2015   #29
Nematode
Tomatovillian™
 
Join Date: May 2012
Location: massachusetts
Posts: 1,710
Default

Quote:
Originally Posted by Worth1 View Post
The main reason I was thinking about the Presto is I can use it in the glass top stove.
My stove says I can the the presto site says I can if the stove says I can.
(Yes my stove talks to me).
All American says not to because of the weight but they say that on their smallest canner.
The other thing is the indentation on the bottom of the canner they say or I read somewhere could cause a vacuum on the stove.
All of my large kettles and post have this same indentation and I have never had a vacuum.



Worth
I didn't read the directions, DW said you can't use it on the glass stove, Looked at her and said if it breaks we can get gas, she said pressure can away!
Glass is still going strong. Just my experience.....
Nematode is offline   Reply With Quote
Old August 17, 2015   #30
coronabarb
Tomatoville® Recipe Keeper
 
coronabarb's Avatar
 
Join Date: Jan 2006
Location: Roseburg, Oregon - zone 7
Posts: 2,821
Default

Ha, ha nematode. I hate electric stoves. Maybe I too should can away and not worry if it breaks. Btw, we are putting in a propane tank at the new house so I will have a gas stove top. Have I mentioned how much I hate cooking with an electric stove?
__________________
Corona~Barb
Now an Oregon gal
coronabarb is offline   Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 09:49 AM.


★ Tomatoville® is a registered trademark of Commerce Holdings, LLC ★ All Content ©2022 Commerce Holdings, LLC ★