Homemade Condensed Soups

[BadRabbit]

The "Back of the Can Cuisine" thread got me thinking:

Has anyone made their own condensed soups and canned them?

Is it just a matter of reducing to that consistency?

I just think all the old casseroles might be more delicious if they were made with homemade soups plus it would be nice to make up big batches so that I would have classic homemade soups available at a moments notice.

[FoodMuse]

BadRabbit

This is an interesting idea. I think we need advice from our food science geeks and canners to let us know if creamed soups thickened with flour hold up under canning. I know they don't freeze well.

I imagine a tomato soup would can very well, not so sure about a cream of mushroom.

[angevin]

At the risk of giving up trade secrets...nah...all of this is common knowledge...

First, remember that only highly acidic soups can be safely "canned". Low acid foods must be "cooked" under pressure to achieve very high temperatures - the risks involved in not suffiently reaching the time/temperature necessary to kill organisms can be deadly. So make sure you do your research.

Second, there are modified starches used to withstand these high temperatures, but I'm not sure how available they are at retail.

As for condensing, no need to reduce, just add half the water before canning.

[DanM]

Another approach would be to vacuum pack and freeze the soups. As angevin said, the easiest way to "condense" a soup is to leave out some or most of the broth, stock or water.

Dan

[BadRabbit]

My idea to reduce instead of leaving out water is so I could properly season. It seems it would be much more difficult to determine seasoning the other way because I don't usually use recipes for soup.

I did realize that this would be a pressure cooking situation.

[thock]

According to the (U.S.) National Center for Home Food Preservation, it's not a good idea to can (even pressure can) cream soups or soups with more than half the jar volume taken up by non-liquid ingredients. If you have too many solids in the jar, there could be a lack of adequate convection and the center may not reach the right temperature depending on the processing time. And if you process longer, one, you don't know how hot the center gets, and two, you may be reducing the flavor and textural quality of the canned food.

That said, we're all (mostly) adults, and we can make our own decisions. It's just not recommended.

NCHFP

I have not been able to wrap my head around the difference between canning single veggies or meats and canning combinations in liquids that can then be called soups. But the recommendation still stands by the NCHFP, which does extensive research on such subjects.

[BadRabbit]

What is different about the process used by Campbells over what one would use at home? It's obvious that it's possible to safely can it though I guess the feasibility of doing it at home is a question.

[angevin]

"I have not been able to wrap my head around the difference between canning single veggies or meats and canning combinations in liquids that can then be called soups. But the recommendation still stands by the NCHFP, which does extensive research on such subjects."

Heat penetration. Much greater through a liquid medium than through solid.

Campbell's has a staggeringly extensive thermal processing history, with a program of highly disciplined testing to ensure the safety of its canned products. You can imagine the importance of that focus - it only takes one error to bring a company this size to its knees.

Disclosure - Yes, I do work for Campbell's.

[angevin]

"Heat penetration. Much greater through a liquid medium than through solid."

As a real life example, think about sticking your hand in boiling water as opposed to an oven set at 200 F.

Your nervous system will respond much more quickly in the water medium due to the rate of heat penetration.

[Mjx]

I cook down soups to reconstitute, but I freeze them, instead of canning.

[thock]

"I have not been able to wrap my head around the difference between canning single veggies or meats and canning combinations in liquids that can then be called soups. But the recommendation still stands by the NCHFP, which does extensive research on such subjects."

Heat penetration. Much greater through a liquid medium than through solid.

Yes, however, the NCHFP recommends FILLING the jars with beans and then topping off with liquid an inch under the rim for just canning plain beans, yet if it's SOUP, you're only supposed to fill the jars halfway with beans and liquid, then top off to an inch under the rim with more liquid. Seems like a bit of a contradiction to me...

For an example using beans canned alone and beans in soup, see below. For soups, they say you don't have to cook the beans as long as you do for straight canning.

canning dried beans "Place dried beans or peas in a large pot and cover with water. Soak 12 to 18 hours in a cool place. Drain water. To quickly hydrate beans, you may cover sorted and washed beans with boiling water in a saucepan. Boil 2 minutes, remove from heat, soak 1 hour and drain. Cover beans soaked by either method with fresh water and boil 30 minutes."

canning soups "For each cup of dried beans or peas, add 3 cups of water, boil 2 minutes, remove from heat, soak 1 hour, and heat to boil; drain."

ETA: links and info about differing instructions for bean canning

Edited February 25, 2011 by thock (log)

[Blether]

Canning dried beans... how many years exactly are we expecting to do without any harvest ?!!

[angevin]

"I have not been able to wrap my head around the difference between canning single veggies or meats and canning combinations in liquids that can then be called soups. But the recommendation still stands by the NCHFP, which does extensive research on such subjects."

Heat penetration. Much greater through a liquid medium than through solid.

Yes, however, the NCHFP recommends FILLING the jars with beans and then topping off with liquid an inch under the rim for just canning plain beans, yet if it's SOUP, you're only supposed to fill the jars halfway with beans and liquid, then top off to an inch under the rim with more liquid. Seems like a bit of a contradiction to me...

For an example using beans canned alone and beans in soup, see below. For soups, they say you don't have to cook the beans as long as you do for straight canning.

canning dried beans "Place dried beans or peas in a large pot and cover with water. Soak 12 to 18 hours in a cool place. Drain water. To quickly hydrate beans, you may cover sorted and washed beans with boiling water in a saucepan. Boil 2 minutes, remove from heat, soak 1 hour and drain. Cover beans soaked by either method with fresh water and boil 30 minutes."

canning soups "For each cup of dried beans or peas, add 3 cups of water, boil 2 minutes, remove from heat, soak 1 hour, and heat to boil; drain."

ETA: links and info about differing instructions for bean canning

Is the procedure described before processing? If so, it sort of makes sense. Although without looking at the soup recipe, I'm not sure why the difference - are there other ingredients in the soup that would require a more severe thermal process? If so, than cooking longer and/or at a higher temperature would "finish" cooking the beans in the soup. And because the beans weren't fully hydrated you would need more water for them to absorb.

Not sure why the soup would require a more severe process though, unless there were other ingredients in there that impede thermal penetration. Another thought, are the straight beans "acidified"? (Is there citric acid in the recipe?).

Without more detail, it's hard to say where that procedure is coming from. So many things can affect heat penetration; perhaps since the soup recipe is "unknown", an overkill process is employed to be on the safe side.

[angevin]

Ok, sorry. I just read the info on the links.

The process time is actually longer for the straight beans, which makes sense. (Higher solids, longer process.) For the soup, they caution that dried beans must be fully hydratedbefore processing. Which also makes sense since you don't want to start with beans with a very high solids level before processing. (Too much variability/ unpredictibility in solids content during the thermal process.)

What doesn't make sense is the method for fully rehydrated, which is nowhere near long enough. I think they missed a step after the second boil.

[thock]

Canning dried beans... how many years exactly are we expecting to do without any harvest ?!!

It's not so much expecting to do without harvest as it is a convenience issue. Say you want to have beans with your dinner, but you have 20 minutes to get dinner on the table. Rather than having to wait on dry beans cooking, you just open a jar (or commercially-processed can) of beans, and there you go. Highly convenient.

[thock]

Angevin, that's my whole point: There's conflicting information. And unfortunately, they're out of funding, so they're no longer taking questions.

You're probably right about the shorter processing time for soups being due to the higher water content. Personally, rather than just going with the soup processing time, I'd go with the longest processing time listed for the ingredients in the soup. For example, I'd go with 90 minutes for soups with beans, rather than 75 minutes, for a quart-jar lot. Just to be on the safe side. Plus, I like my soups to be a little less liquidy. I may be taking chances, but I figure if I process for the time specified for the longest-processing ingredient, I'm probably safe. I don't thicken soups, either.

[BadRabbit]

If I can readjust the aim on this thread for a minute, why is it not possible to can cream based soups at home?

What deleterious effects could I expect from pressure cooking for longer periods? Couldn't I probe the soup to make sure proper temps had been met?

Also, other than a general statement that Campbell's has been doing this for years, I haven't seen anyone directly address how they are able to produce a product unproducable at home.

Do they use higher pressure?

Someone mentioned different starches but I don't see anything on the label that would be difficult to procure. Which ingredients would be different?

[thock]

I'm sorry, I believe I was the one who derailed the thread.

The concern, I believe, with home canning dairy products, is two-fold. One, dairy products contain a lot of fat, which can possibly interfere with the sealing of the lid. Another is the quality of the finished product. Some people DO can dairy products, regardless of the NCHFP's recommendations against it, and they report that the milk (generally speaking) separates, which is not particularly pretty. Also, the milk tends to get an overcooked taste which is not appealing.

Jackie Clay, from Backwoods Home magazine has some recommendations for processing times with milk, but I'm not sure I trust her times. You can do a search for her name and come up with a bunch of info.

As far as probing the soup during processing, I'm sure that would require specialized equipment, including a specially-ported jar and a specially-ported pressure canner.

While there are specialized ingredients used by commercial processors, I think a lot of the reason some people (like me, for instance) like to produce things at home is to avoid these ingredients. Plus, it's possible that they are operating at a higher pressure. Unless you worked for a commercial processor, I don't think you can find out. And I'm fairly sure that there are probably some things people like angevin cannot disclose because of trade secrets agreements.

What would be nice is if there were some lab set up somewhere to conduct research on these things. There was one at the University of Georgia (NCHFP), but it no longer has funding, and even when it did, it didn't do a lot of testing that would have perhaps been valuable to this discussion. And its focus was more strictly on the generic home food preserver, not on people like us who want to do fancier things.

[Blether]

It's not so much expecting to do without harvest as it is a convenience issue...

... and a forethought issue that meant you didn't can beans when they were ripe from the vine, or didn't think you'd need more than you were canning. Circumstances piling up on each other, eh ?

Sorry, there you were back on the rails again and I just can't resist keeping on chugging along this siding. I enjoyed your post introducing Jackie Clay &c - clearly you know more about home canning than I do. Are we now waiting for a train to come along carrying someone who does home canning and is interested enough in doing it to cream soups to give it a shot ?

[thock]

I'll derail again briefly to clarify something...

The beans I'm talking about canning are dried beans, such as pintos, kidney beans, etc. Something that typically takes quite a while to cook from dried, and I don't typically grow drying beans in my garden...until this coming year, when I plan to try to grow some pintos and some dark red kidney beans just for fun. Those I will dry. As I run out of canned beans, I will can up more to take their place. Dry beans take up a lot less space than do jars of canned beans.

It's WAY more convenient to have a jar of beans to open after coming home from your 8-5 job, with 30 minutes to make dinner and eat before you have to get to a meeting or some other function. Or it would be, if your S.O. actually ate beans, which mine does not. The bean issue was just a handy example to contrast between the two methods.

Sometimes, even with all the forethought in the world, life throws you a curveball which you have to deal with in some fashion. That's why convenience foods, commercially produced or home made, are so convenient and popular.

To bring the topic back on track, after the brief derailment, I have done some more looking since I last posted, and it appears that the biggest problem with canning cream soups (aside from the lack of info on processing times) is that it just doesn't work too well. The milk's enzymes tend not to be inactivated (perhaps???), and things separate and look evil. Even Jackie (who employs methods that strike me as a bit risky) doesn't like to can milk-based things because of the separation issue. I think that most commercially-canned cream soups are highly dependent on modified food starches, etc. to maintain the consistency of the liquid.

I'm far from an expert on home canning. I've only done a bit of it, but I have done a lot of research because I wanted to see if it was possible to home-can cream soups or condensed soups, too. I came away from my research with the idea that it wasn't worth the trouble and energy cost to end up with something that I wouldn't eventually want to use. So, instead, I can non-condensed soups. But I employ the longest single-ingredient processing time, because it makes me feel better, not because I have any empirical evidence that it IS better.

ETA stuff about growing beans.

Edited February 25, 2011 by thock (log)

[Blether]

I've been interested in the thread partly because I like cream soups (cream of tomato !! drool) and I know freezing them tends to spoil the texture, too. It sounds like the solution for more-convenient-homemade-cream-soup is to freeze / can the soup base (i.e. the soup without the cream) and add fresh cream after you take it out again. That way everyone wins, since leaving the cream out is a form of condensing, too - and cream soups often being all- or part-pureed, sounds like it makes them good canning candidates.

Since we're talking about condensed soups, we were never expecting, say, to reheat them in the canning container. De-canning, adding water and heating is only harder than doing the same with cream by a factor of having the cream available vs running the tap. And think how much modified starch - and always-the-same base stock - you'll be avoiding.

[thock]

I tend to agree. And since cream, itself, freezes nicely, you can still have that on hand.

As far as non-creamed condensed soups, I'm still stuck on the conflicting information from NCHFP. As they're not answering questions, right now, I can't ask, but it seems to me that if one were to process a less-liquidy soup for a longer time than is called for in the soup-canning instructions, you might be able to get away with it.

My reasoning is thus:

Canning a soup with an unspecified combination of meats, veggies and beans calls for preparing the ingredients as if for canning by themselves, plus cooking the meat until tender, plus hydrating the beans. The ingredients are then combined with the soup liquid of choice and boiled for 5 minutes, after which they are canned, half solids, half liquids, at 11 psi for 75 minutes at at or below 1000 ft. of elevation from sea level. We're going to assume we aren't dealing with seafood for the purposes of this discussion.

Canning a fully-packed (hot pack) jar of meat strips, chunks or cubes in broth or water calls for cooking the meat until rare, filling jars with the pieces, then pouring boiling broth or water until there's an inch of headspace left. After that, the jars are processed at 11 psi for 90 minutes at or below 1000 ft. of elevation from sea level. Also, mixed vegetables meant for canning as a mix solely of vegetables, calls for the same processing pressure and time after an initial boiling for 5 minutes in the packing water.

If a FULLY-PACKED jar of meat (or beans, or veggies) is considered safe to consume after 90 minutes of processing, then it seems to me that a less-than-fully-packed jar of meat and veggies, with the remaining space being taken up by soup liquid (stock, water, etc.) should also be safe to consume after 90 minutes of processing. Less solids leads to more convection, right?

So, without recommending this to anyone (to avoid liability) I will state that I have no compunctions about employing this method to can soups with less liquid for my own family. This will naturally lead to a more "condensed" soup than is specified in the NCHFP guidelines, but it is still something I feel comfortable about, even without empirical evidence. Other than the reduction in liquids/increase in solids from the recommended soup canning instructions to the single-product canning instructions, the only difference seems to be the processing time, and 90 minutes is more conservative than 75.

Others may not agree with me, but that's ok. I'm not trying to feed them, just my family.

[thock]

The "Back of the Can Cuisine" thread got me thinking:

Has anyone made their own condensed soups and canned them?

Is it just a matter of reducing to that consistency?

I just think all the old casseroles might be more delicious if they were made with homemade soups plus it would be nice to make up big batches so that I would have classic homemade soups available at a moments notice.

BadRabbit,

Something else just occurred to me. A long while back, I was looking for a replacement for canned cream of mushroom soup. I found out that I could make a big batch of light roux and refrigerate it. Then, when I wanted to make a casserole (like tuna noodle or some such), I could heat some cream and milk with some mushrooms and reduced chicken stock (and other veggies if I like) and add the roux to thicken. It works rather well that way. It doesn't take a whole lot of extra time to do it this way, either, and I typically have all the ingredients I need on hand. I use dried mushrooms (that I dehydrate when I pick them up from Costco) and home-made and -canned chicken stock. (I reduce my stock by a LOT before canning it.) I'm a milkaholic, so there's always dairy around, too.

I used jackal10's bechamel recipe to come up with this process, although I think that the milk and stock combination is more like a veloute, but I could be wrong.

Anyhow, I would imagine that you could do the same, and if you wished, you could probably can the mushrooms (or whatever else it is you want to have cream-of) in the stock and just add the dairy and the roux as you're making the rest of the dish.

I have found, by the way, that refrigerated roux is brick-like, so it's hard to get out what you need unless you refrigerate it in small quantities. I think an ice cube tray would be useful for this.

[angevin]

"While there are specialized ingredients used by commercial processors, I think a lot of the reason some people (like me, for instance) like to produce things at home is to avoid these ingredients. Plus, it's possible that they are operating at a higher pressure. Unless you worked for a commercial processor, I don't think you can find out. And I'm fairly sure that there are probably some things people like angevin cannot disclose because of trade secrets agreements."

While there are some things I can't disclose, most of traditional thermal processing is pretty standard. I can tell you that a commercial canner the size of Campbell Soup employs some of the best processing authorities in the world. That combined with high-tech instrumentation, allow us to zero in on a specific soup recipe and determine the minimal process that will still ensure commercial sterility. Something we continuously work on, because it does result in some pretty significant quality improvements, as well as cost savings with increased throughput.

Since the guidelines for homecanning are very conservative and allow for worst case scenarios, most home-canned soups are severely over-processed.

Come-on guys, is there anything better than Campbell's Tomato Soup, reconstituted with fresh whole milk???????

Edited February 26, 2011 by angevin (log)

[angevin]

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