What is in the salsa that could go bad?
It isn't that something could "go bad" necessarily although bacteria (including botulism) and molds are very real possibilities.
It is because
(1) there are no known processing times for quarts,
(2) salsa is a mixture of acid and LOW-acid ingredients rather than all acid ingredients and low-acid ingredients are normally pressure canned only,
(3) to be both tasty AND safe it requires a fine-line balance of acid for the pH and BWB processing and while you could, in theory, process the he*l out of the quarts in a pressure canner you wouldn't want to eat the results, and
(4) it is eaten fresh from the jar so any bacteria that may have developed during shelf storage aren't killed by further cooking after opening.
NCHFP has a number of research publications on salsa safety available on their website if you want to review them.
It is a density issue in cases like that. The heat cannot penetrate the larger jars in a manner in which it will killl all the bacteria. It is never safe to use a larger jar than called for.
I have done over 100 quart jars of Annie's Salsa. Never knew I could not do it. I just did it. My mother always told me I can do anything I make up my mind to do.
Can is often used where may or should ought to be.
You can do it, you should not, but no law says you may not.
Since salsa contains low-acid ingredients like peppers, onions and garlic it is one of the riskier propositions. Especially because, as mentioned, it's eaten from the jar without additional cooking.
So hypothetically, there could be botulism in untested home-concocted and canned recipes or in recipes canned but with inadequate heat penetration.
There's an article at the link which explains some of the issues.
The main issue with quarts is that size jar has not been tested. Perhaps the processing time is sufficient for safety, perhaps not. It's an unknown.
But really, no one here is controlling the choices any canner makes, so if anyone wants to can salsa in quarts, they can do it. After all, we're not eating it.
Here is a link that might be useful: Safety Important when Preserving Salsa
I don't know whether it's been discussed before, but can anyone say why salsa in quarts hasn't been tested? Is it because of the cost of testing or lack of interest? Or is it just that they have tested and haven't yet found a safe recipe/processing time for quarts? I prefer pints for salsa anyway, but I'm just curious as to how it all works.
I would guess that it's lack of funding. I asked once about pressure canning tomato paste (which is a pretty basic product) but no testing had been done.
For years the processing time for fish was limited to 8 oz. jars and pints. Finally in this last edition of So Easy to Preserve a processing time was added for quarts.
It is also true that sometimes the longer processing time would have an effect on quality. Some products have even been re-tested (like summer squash) but testing demonstrated that a processing time sufficient to cover all the variables in pH and water activity would have been so long what the canner would have ended up with was squash "mush." So they just pulled the recommendation.
It's ironic that at the same time there's a resurgence of interest in canning and canning safety is so important, the Extension services are struggling with funding.
As Linda Lou said recently, things are now so bad that the NCHFP is basically on "inactive" status.
We're going to see a lot less testing and I would venture to guess any new recipes will come from Ball and Bernardin. The Jarden Corporation is making money hand over fist. (I believe 20%+ increase in sales each of the last two years - I should buy stock.)
I agree with Carol as to the reasons but I think that quality of the end product if canned in quarts for a sufficient amount of time is the primary reason.
NCHFP was doing a good amount of research into salsas before all the funding cuts. But quarts weren't the focus even then because of the effects of longer processing required.
One also has to consider the safe fridge life of a quart of salsa once opened. It isn't something that is commonly consumed in quart amounts all at one time. So it sits, opened, in the fridge for the rest of the time. Given its borderline pH, its unknown processing time, the bacterial growth refrigeration only slows but doesn't stop, the safety of the left-overs would quickly come into question. Pints have a limited fridge life too but the odds are they will be consumed faster.
Like Kay said above, what someone "can" do and what someone "should" do aren't the same thing. Each person has to make that choice for themselves.
But for me, since (a) there are no advantages in canning it in quarts, and (b) there are potential disadvantages, and (c) no one has any idea whatsoever how long the quarts would have to be processed and they are just guessing, common sense says do it in pints only.
In one of the Annie's salsa threads, Annie herself says that Extension approved BWB at 15 minutes for pints and 20 minutes for quarts.
Personally I don't can it in quarts, since I could never eat that much salsa in a sitting. But I've told other people it was OK to use quarts if they use this recipe and this source.
There are also many discussions about how that early approval for quarts was canceled/withdrawn/voided whatever you want to call it. If you have kept a copy of the recipe that info needs to be added to it.
Good rule of thumb: IF IN DOUBT, THROW IT OUT. There are several recipes which take into account canning in quart jars. In MOST of the recipes I have, it's the time suggested in the water bath. It's usually 10-15 minutes longer for quarts than for pints. You are making a hugh batch, the same mixture is going into jar 1 as jar 12. I use several sizes of jars for salsa and PER THE RECIPES, adjust the process time. Usually the 8oz and the pints (according to 'The Complete Book of Home Preserving' by Ball)have the same process time. Here is a site I have used upon occasion: www.canning-recipes.com.....Ya know, thank goodness my great-granny, granny, aunts & mom taught me to can. Common sense is a great asset!
Do what you want, but I will not tell you it is safe to process in quarts. It is never considered safe to use a jar larger than listed in a recipe. I do not know why Annie woulld have been told it was fine to use quarts. Especially since no other of the USDA/ extension recipes for salsas are safe for quarts.
There is Mexican tomato SAUCE in quarts, but the density of that sauce is different than the salsas and also the Mexican tomato sauce is pressure canned, not done in a BWB canner.
There is no way to just add time to canning recipes, use a larger jar, and insure it is safe.
Yes, there are many recipes that account for canning in quarts. There are other recipes, like full-sugar jams, that don't, but due to the nature of the product, risk is negligible. Even then the risk is mold and loss of product, not safety.
However, salsa is not one of those options.
If bacteria responded to common sense and if I lived in the world my great-grandmother did, I'd be more influenced. But in the case of canning I prefer science. New strains of resistant bacteria (witness the more powerful flesh-eating bacteria presenting such terrible problems in hospitals and antibiotic-resistant strains continuously evolving) now exist.
The problem with Annie's salsa is that there are still available threads on this Forum going back to 2005. In the world of canning and food research, 5 years is an eternity.
During that time the Extension service which originally recommended a time for quarts pulled that recommendation and also the reduced-vinegar version which was pressure-canned.
Are those options unsafe? It's an unknown. But lacking the resources for testing, Michigan Extension rescinded those recommendations. Annie made that clear in later threads, so in referencing Annie's salsa, it's important to check the latest postings, not the earliest.
Again, though, people do what they want. All we do is point out potential risk.