Pressure canning filter
August 25, 2010 7:34 AM Subscribe
It's my first harvest season with a pressure canner, and after a few successful runs with very basic low-acid things, I'd like to try canning basic (meatless) spaghetti sauce/tomato soup base. How freely can I improvise a recipe based on what's in my garden? How do I know how long to process it?
The internet keeps turning up the same fussy USDA recipe for spaghetti sauce, which I'm not interested in because a) I don't have all the ingredients in my garden, and b) I'd like to keep it sugar-free. Ideally, this will be somewhere between sauce and seasoned/stewed tomatoes, something I can thicken with tomato paste and use for pasta OR cook up into a soup. I'm thinking tomatoes, fresh herbs (basil, parsley, oregano?), garlic, salt & pepper. Do I need a recipe? Acidity isn't an issue because I'm using a pressure canner, right? Is olive oil ok, or will it ruin the seal?
The internet keeps turning up the same fussy USDA recipe for spaghetti sauce, which I'm not interested in because a) I don't have all the ingredients in my garden, and b) I'd like to keep it sugar-free. Ideally, this will be somewhere between sauce and seasoned/stewed tomatoes, something I can thicken with tomato paste and use for pasta OR cook up into a soup. I'm thinking tomatoes, fresh herbs (basil, parsley, oregano?), garlic, salt & pepper. Do I need a recipe? Acidity isn't an issue because I'm using a pressure canner, right? Is olive oil ok, or will it ruin the seal?
Do you have something like the ball blue book, or the big book of home preserving? I would think that would give you some places to start.
(actually, I thought that you could can meatless tomato sauce in a boiling water canner. But then, I don't have a pressure canner yet!)
posted by leahwrenn at 8:31 AM on August 25, 2010
(actually, I thought that you could can meatless tomato sauce in a boiling water canner. But then, I don't have a pressure canner yet!)
posted by leahwrenn at 8:31 AM on August 25, 2010
leahwrenn, you can use a boiling water canner for tomato sauce but you need to add an acid to the sauce to bring up the ph.
posted by cooker girl at 9:36 AM on August 25, 2010
posted by cooker girl at 9:36 AM on August 25, 2010
cooker girl is right, except that adding acid *lowers* the pH. Ideally to a value below the critical 4.6 threshold.
posted by janell at 11:05 AM on August 25, 2010
posted by janell at 11:05 AM on August 25, 2010
Do I need a recipe? Acidity isn't an issue because I'm using a pressure canner, right? Is olive oil ok, or will it ruin the seal?
You do need a recipe. With pressure canning, acid isn't the only factor you need to consider -- the density of the jar's contents is also very important. That's why you need to use a tested, approved recipe -- adding pretty much anything (vegetables, meat, liquid) will change both the pH and the density.
Oil, as a general rule, is a no-no. However, there are some sauce/stew recipes that do contain oil and have been approved by the USDA.
This isn't really one of those times where you want to thumb your nose at the authority figures because they're standing in the way of something you really need to do. What you're talking about is the risk of botulism, so it's best to play by the rules.
If you want to make a sauce using a recipe not tested for canning, you need to freeze it instead.
If you don't have an approved recipe in any of your books, you might consider asking in the Harvest forum at GardenWeb. There are a couple Master Food Preservers there who are very knowledgeable and helpful, and they're often more than happy to provide recipes and advice. (Be warned, though, they'll also lecture you if you ask them whether it's okay to make up your own canning recipes.)
Also check out the Ball Complete Book of Home Preserving. It has a wider variety of recipes than the Ball Blue Book.
posted by mudpuppie at 12:13 PM on August 25, 2010 [2 favorites]
You do need a recipe. With pressure canning, acid isn't the only factor you need to consider -- the density of the jar's contents is also very important. That's why you need to use a tested, approved recipe -- adding pretty much anything (vegetables, meat, liquid) will change both the pH and the density.
Oil, as a general rule, is a no-no. However, there are some sauce/stew recipes that do contain oil and have been approved by the USDA.
This isn't really one of those times where you want to thumb your nose at the authority figures because they're standing in the way of something you really need to do. What you're talking about is the risk of botulism, so it's best to play by the rules.
If you want to make a sauce using a recipe not tested for canning, you need to freeze it instead.
If you don't have an approved recipe in any of your books, you might consider asking in the Harvest forum at GardenWeb. There are a couple Master Food Preservers there who are very knowledgeable and helpful, and they're often more than happy to provide recipes and advice. (Be warned, though, they'll also lecture you if you ask them whether it's okay to make up your own canning recipes.)
Also check out the Ball Complete Book of Home Preserving. It has a wider variety of recipes than the Ball Blue Book.
posted by mudpuppie at 12:13 PM on August 25, 2010 [2 favorites]
This is a pretty good rundown of the issue of botulism and the argument against improvising canning recipes. The thing about botulism is that although serious cases of food poisoning by it are quite rare, a canned food presents the rare environment where it could proliferate, you can't detect it, and it can be fatal.
posted by nanojath at 4:45 PM on August 25, 2010
posted by nanojath at 4:45 PM on August 25, 2010
cooker girl is right, except that adding acid *lowers* the pH. Ideally to a value below the critical 4.6 threshold.
Ha, oh, yeah. Sorry about that! Previewing is such a good idea.
posted by cooker girl at 6:00 PM on August 25, 2010
Ha, oh, yeah. Sorry about that! Previewing is such a good idea.
posted by cooker girl at 6:00 PM on August 25, 2010
This thread is closed to new comments.
You're correct about the acid, too. The pressure canning takes care of that.
posted by cooker girl at 7:50 AM on August 25, 2010