Canning question - pressure canning

[mzgarden]

The answer to this is probably obvious but it eludes me. 

Just to be clear, this is about pressure canning recipes - no intent to water bath.  I completely get the concern if we're talking water bath.

Why do pressure canning recipes for things like stewed tomatoes, etc warn against changing the ratios of tomatoes to peppers, onions, etc when on the flip side, we pressure can raw meat or cooked meat products (soups, stews, etc.)?

I don't understand why when pressure canning, the ratios of the vegetables should matter, if there is no issue pressure canning other things that have no/very little salt, vinegar, sugar to keep.

What am I missing?

Here's one example:

At the beginning:

If you are Canning Stewed Tomatoes, you will be adding peppers and onions. Celery is optional. Since you are adding other vegetable ingredients botulism is a risk. This MUST be pressure canned.

Then in the instructions:

Chop your onion and pepper. Remember when canning stewed tomatoes like this you can safely adjust the type of pepper you use in stewed tomatoes. Use a hotter variety for a spicy jar. Use bell or banana peppers for mild. Just don't change the quantity or ratio of tomatoes to vegetables.

[MeandTK]

I am going to assume that the recipe was not fully updated when the move was made from wTer bath canning.
It shouldn't matter when pressure canning, but I'm a neophyte who doesn't know much.

[feather]

Salsa (in half pints or pint) has a specific ratio of tomato to onions/peppers and is pressure canned for 15 minutes. (the ratio and size of jar is important in the timing)

Peppers alone (in half pints or pints) is pressure canned for 35 minutes. (the ratio (all peppers) and size of jar is important in the timing)

Stewed tomatoes (tested in both pint and quart jars) with a ratio of tomatoes to peppers/onions is pressure canned for 15/20. (a high ratio of tomatoes to peppers/onions and sizes of jars changes the timing too)

It looks to me like peppers need more time to process by pressure canning, so adding more peppers changes the timing of the pressure canning.

Beyond the pressure canning times, you ask:

I don't understand why when pressure canning, the ratios of the vegetables should matter, if there is no issue pressure canning other things that have no/very little salt, vinegar, sugar to keep.

What am I missing?

There is also the density issue. If the choice of amounts of vegetables change, the density of the contents of the jar change. If jars are overly dense (like the density of mashed sweet potatoes, or mashed potatoes), then they cannot be safely pressure canned. The heat doesn't reach in the very interior of the food, to make it safe.

They (university extensions) don't test every ratio of foods (say tomatoes to peppers/onions) in every size jar, and that is just a funding issue but a good reason not to use untested recipes.

Density issues arise in all kinds of canning recipes. Like home canned soups, the density needs to be 1/2 liquid to 1/2 solid.

This is a good link for make your own choice of home canned soup.

www.healthycanning.com/usdas-your-choice-soup-recipe/

Density issues with canning raw hamburger--it isn't approved to pack the jars with raw hamburger by a university extension office or national canning blau blau. People do it, I won't chance it for my family. Hamburger is cooked first, water added, fat skimmed to allow it to be a less dense mixture.

[mzgarden]

feather , Excellent help, thank you. My plan is to pressure can tomatoes, peppers, blanched onions and okra using the half solids/half liquid rule in pints for 30 minutes, similar to a stewed tomatoes but with small bits of okra and some onion. I'll make sure my cut up bits are similar in size using a chopper making them pretty small, so density should not be an issue. Canning salt will be in there too.

The link you provided was new to me and very interesting.

Appreciated the help - the answer was simple, I just didn't know it so I appreciate the help.

[feather]

mzgarden, most of the time when I make things, I write down the recipe, except with canning. (except ketchup) I've been looking up recipes and comparing them, each and every time I can something because I don't want to make a big dangerous mistake. Also those recipes change, the tested ones, so I don't even buy books anymore for canning. Pretty much anything I've needed has been on the internet-university extension sources and National Canning Blau Blau.

I also love reading blog recipes, some people are pretty good at quoting accepted tested sources, and some not. It's still interesting and thought provoking.

I'm still learning and will probably always be learning, as my memory isn't that great for things I only use once a year or for one season a year, like canning. I also liked that link with the choose your own soup recipe.

DH and I are thinking about canning chicken when it goes on sale. Chunks of chicken raw packed, is approved. I haven't decided on the size of jars to use if we do that.

[mzgarden]

Thanks. I've done the raw pack chicken following onlnine instructions as well. Generally I don't get creative, I can one thing at a time. This time, I have bits I need taken care of so I was out of my comfort zone with the combination. The link helped, as did several other University links for canning things like stewed tomatoes and tomatoes & okra, etc.