You can only use it for pickles not canned plain in a presssure canner.

Yep used in pickling recipes its fine. Enough vinegar to off-set its low acidity. There is a great Zucchini Relish recipe here. And there is an approved recipe for Canned Tomatoes with Zucchini too at NCHFP.

Dave

Here is a link that might be useful: Canned Tomatoes & Zucchini

Linda - my understanding is that the recomendation to NOT can zucchini and other summer squashes had to do with a quality issue - the canned product turned to mush. Not a safety issue. Can you clarify. Thanks.

It is explained in more detail at NCHFP FAQS. It is a combination of safety issues related to the unknown pressure canning processing time and quality.

Why is canning summer squash or zucchini not recommended?

Recommendations for canning summer squashes, including zucchini, that appeared in former editions of So Easy to Preserve have been withdrawn due to uncertainty about the determination of processing times. Squashes are low-acid vegetables and require pressure canning for a known period of time that will destroy the bacteria that cause botulism. Documentation for the previous processing times cannot be found, and reports that are available do not support the old process. Slices or cubes of cooked summer squash will get quite soft and pack tightly into the jars. The amount of squash filled into a jar will affect the heating pattern in that jar. It is best to freeze or pickle summer squashes, but they may also be dried.

Dave

It is a density issue, so it is about the safety of the zucchini. It is basically the same as any pureed vegetable when canned. The heat cannot penetrate the food properly. Added with the tomatoes, in the right proportions, changes the ph and density.

I certainly want to do things safely, but I've never had a problem with canning zucchini. Perhaps I use a different recipe. I ate the last quart of 2009 zucchini chickpea potato soup last week. It was right at the one year mark. The way we eat zucchini, if it's not fresh it's as a flavoring agent and we don't mind it being mushy. I do add a fair squeeze of lemon juice per jar.

I know that no one wants to sound like they are suggesting that people do things that are considered contrary to conventional wisdom, but does anyone have the answer why something that had been fine is now magically not ok?

It's not magically no longer OK. For one thing, testing has changed.

As an example, pumpkin butter used to be OK to can. But newer testing with a wider range of samples revealed radical variations in pH and water activity. The pumpkins from source to source varied so much it was extremely difficult (if not impossible) to arrive at a processing time which 1) covered all variables 2) assured quality - i.e. a pleasureable eating experience.

It is entirely possible for people to can according to out-dated guidelines and not experience ill effects.

Botulism is rated by the CDC as low-frequency (It doesn't happen often.) but high-risk. So the odds against getting it are pretty good. The problem is, if you do, you're not going to enjoy the experience. That's assuming you survive.

A lot of people reduce risk by using the canned product in a heated dish. Your soup is an example. Cooking at a good temperature (reaching the boil) for 20 minutes or so kills any active toxins.

That's why many old-timers survived some rather primitive food preservation strategies. Meat and veggies were often cooked for long periods before consumption. I know my grandmother wouldn't even consider green beans that hadn't been cooked on the stove for at least a half-hour. If they weren't olive green and soft as baby food, they weren't beans.

However, once people know there's a risk, it's up to them to decide if they want to follow current guidelines or not.

Carol

I have been teaching food preservation for 12 years and I have never known it to be safe to can zucchini other than pickled or in exact amounts added to tomatoes.

My canning collection isn't complete, but the last resource I have that lists canned summer squash is a 1992 Ball Blue-Ribbon Cookbook. I don't know when it changed after that, but clearly it's been quite some time.

Carol

So when I find a recipe online and it says something like "play around with it. You'll find what you like and which combination is enjoyed most by you and your family" I should be leary because those recipes they are following aren't approved? I'm really learning that canning is more and more of an exact science than I had previously thought.

...I found this thread when I was wondering if I can shred zucchini and then can it with water for use later on in zucchini bread...any suggestions on that?

You can shred and freeze it for later use in zucchini bread. But not can it.

Any yes, canning is a science. When you find a feel-free-to-play-around-with-it canning recipe - and there are tons of them out out there on many unsafe sites - you should be more than leery. You should cringe and mutter any favorite 4 letter word. Then quickly leave the site. Or do as many of us do and post a "unsafe recipe" reply. ;)

Dave

If they were saying Play around with this mixed-berry jam and use any combination you like, that's nothing to worry about.

But when they say, Play around with this zucchini soup or Feel free to modify this meaty spaghetti sauce, then it's definitely time to duck out.

Carol

Okay, so reading through everything here and everywhere online, including the USDA, it sounds like they LOST the data on canning Zucchini and just haven't bothered to do the testing again.

They still have instructions for canning Pumpkin cubed. What's the difference if you peel, seed and cube Zucchini and can it with the same processing times?

sounds like they LOST the data on canning Zucchini and just haven't bothered to do the testing again.

Uhhh, no. That is way over-simplified. First because the original supportive documentation for the method may never even have existed and USDA clearly states that the documentation that does exist does NOT support the safety of the old methods because of the density issues it creates.

Slices or cubes of cooked summer squash will get quite soft and pack tightly into the jars. The amount of squash filled into a jar will affect the heating pattern in that jar.

They further discuss the quality issues that arise when pressure canning it.

The issues discussed do not affect pumpkin or other winter squash nearly as much as they do summer squash because of the much firmer texture of winter squash.

But as always, you are certainly free to disregard the guidelines and do as you wish.

Dave

I think one of the riskiest habits in canning is to extrapolate from one situation and apply it to another.

It is true that when the USDA passed along its documentation some was either missing or never saved in the first place. But, that's largely irrelevant because so much time has passed; testing now is much more sophisticated and precise than it once was. New discoveries (and complications) are being revealed every day.

For example, canners still scream about adding acid to tomatoes; but when you see a paste variety coming in at 4.8 or 4.9 pH, that does alter your perspective for a bit. For a long time it just never occurred to people that there might be varieties that low in acidity.

It's not like the USDA/NCHFP had a mission to make life difficult for home canners. They are scientists and they're going to pursue the data. When it doesn't add up to risk-free, they aren't going to approve it, regardless of what the prior standard was.

I really think we discussed the issues pretty thoroughly in previous posts. However, as Dave indicated, we're not the canning police. People do what they do and in most cases manage quite nicely. Only you can assess your tolerance for risk.

Carol

I did a pickled zucchini a few years ago. They were thin sliced and quite mustard-y. We lived. I should look for the recipe.

here is a nice zippy recipe that is boiling water bath safe.

Here is a link that might be useful: zucchini relish

Pickling zucchini and pressure canning plain zucchini are two very different issues.

Pickled zucchini has always been considered safe assuming an approved recipe with sufficient acid is used. But the issue here is canning the plain vegetable. That is NOT considered safe to do.

Dave

Does anybody know how to use dried zuchinni for bread? Trying to free up the freezer by doing more dehydrating but don't know how to apply dehydrated zuchinni to my bread recipes. I use 2 cups frozen or fresh zuchinni in a recipe.

2 choices - measure it before drying and dry 2 cups shredded at a time for packing OR mix 2 cups of water or juice (apple works well) with 1 cup of dried zucchini and soak till rehydrated. You can always add a little more zucchini to the mix if it is still too soupy when rehydrated but don't overdo it or the bread will be too dry.

Dave