I'm relatively new to canning but my understanding is that if you have a high acid mixture (usually means lots of vinegar) it will take care of botulism. Keep in mind that adding oil to anything negates this to some degree and should be avoided at all costs.

A hot water bath is required generally to help kill bacteria but moreso to seal jars for storage at room temperature. If you are not cooking whatever it is you are canning then it's a good idea but again if it's highly acidic (salt helps too I presume) and you aren't looking to store at room temperature it's not a huge concern.

Pressure canners work with higher pressures so they can reach higher temps thus helping you ensure safety and requiring less cooking of your food.

If you are willing to keep your canned goods in the fridge it means that you are able to get away with much much more.

If I made any mistakes or said something that wasn't true feel free to correct me everyone; I'm still learning.

In Europe it's common not to water bath jams. That and some pickled/fermented products (generally refrigerated ones) are the only exceptions I can think of off-hand; other products are either water bath processed or pressure canned (or frozen, dried etc.).

In the U.S. and Canada the common practice is also to water bath jams. Countries like Australia and New Zealand are also beginning to follow that practice in their college food programs.

The line is 4.6 pH. Foods below that line are water bathed (acid foods). Foods above that line (low-acid foods) like green beans and corn, chicken, fish, etc. are pressure canned. Those are the hard-and-fast rules.

There are so many books out there still available, some still in publication, written by well-intended people who haven't kept up with research in food safety. In fact, they're 60+ years behind the times.

By WWII (1943) the USDA was definite on pressure-canning of low-acid products and they were taking about boiling water bath even earlier, WWI (1917).

How can you use older recipes? They need to be modified to up-to-date standards. You can post them here to get recommendations or if you are close to an Extension agency, ask them for assistance.

A lot of those old much-loved recipes have already been modified by Extension agencies, the National Center for Home Food Preservation, the USDA when it was still developing recipes and Ball (USA), Bernardin (Canada) plus respected individual authorities like Ellie Topp and Margaret Howard (authors of "Small-Batch Preserving").

You are definitely not limited to the Ball Blue Book. As with "Small-Batch Preserving" there are many other reliable publications.

The other thing I'd recommend is to get up-to-speed on canning and food safety principles. The NCHFP offers a free online self-paced course (link below). You're reading here. That's a good beginning too.

Meanwhile, if you have a canning book published before 1994 don't use the recipes without checking. And if it's published after 1994 and it's not one of the sources I listed above (including "So Easy to Preserve" by the NCHFP and the new "Ball Complete Book of Home Preserving") I wouldn't trust it regardless of the year without checking here.

Of all the recipes you list above, the only one that might be OK (can't be sure without seeing it) would be the Lime Pickles. The Salsa is probably the most risky.

Good luck. Just keep reading and asking questions and learning. And keep that water bath handy, even if you do hate it. You're going to need it!

Carol

Here is a link that might be useful: NCHFP Books and Home-Study Course

jasonk - You live in Kentucky too? :)

Carol - Don't knock older cookbooks, they have some great recipeis. :) But for things like canning where there have been changes in safety techniques .... I'll be looking for ways to update those old recipies. And on that note, thanks for the tip about Calling my Extension Agent. I am making the call tomorrow. I'll also be checking out the home study course you generously provided.

Don't misunderstand. I'm not knocking old cookbooks. I love my 1948 Kerr Home Canning Book and my old Farm Journal Canning and Freezing book. I'm just saying the recipes have to be approached with care. ;)

Carol

In a nut shell... 99% of the time, for high acid foods acid.

My mother has canned for probably 60 years and has never done anything except open-kettle. That's the way they did things in the old days, and she continues to do it. I mostly do water-bath now, but I still open-kettle my applesauce and all my tomato sauces. I think as long as you are meticulous about cleanliness and temperature, you can get by with it.

Except that botulism doesn't have anything to do with cleanliness. Personally I wouldn't risk it on tomatoes. With applesauce the worst that would happen is mold, but after all the work to make it I'd rather not risk that either.

As Melly said, it doesn't have anything to do with cleanliness. With low-acid foods (and potentially that can include tomatoes) you slap a lid on something and create an anerobic environment that botulism loves. Boiling doesn't kill the spores. It kills the toxins but as soon as the lid goes on, they start growing again.

With high-acid food, you mainly lose quality because the seal isn't as strong, so it's not just mold but oxidation and speedier deterioration.

My 1948 canning book says of "open kettle": "This method has been succeeded by more modern methods. Open kettle canning is not recommended for fruits or tomatoes because of loss of nutritive value of the food and the danger of contaminating the food before jars are sealed."

Now that's just after WWII, so I don't know how old the old days are, but it seems to me that there were a lot of people in the "old days" who were willing to update.

"Some" did things like that in 1950's or later because they failed to keep up with developments in food science. Some people were still driving Model A's too.

They got away with it because they were lucky or because they followed the old rule and boiled everything to death when they opened the jar (for green beans, etc.)

I don't understand why anyone would approach an act as crucial as processing the food we eat as something you can "get by with." It is not a rejection of our grandmothers to adapt to new standards. They did the best they could with what they knew at the time. It's our responsibility to do the same.

I am amazed that so many of us will eagerly adopt new technology in every area but this one. We're on computers discussing archaic methods of food preservation. Now that's ironic.

We're all free here to do what we want, but hopefully newbies understand open-kettle canning hasn't been recommended for the past three generations.

OK, I'll get off the podium. Just my 2¢.

Carol

" I am amazed that so many of us will eagerly adopt new technology in every area but this one. We're on computers discussing archaic methods of food preservation. Now that's ironic. "

Too funny, Carol. Hadn't exactly thought about it that way, but it's true!

I think it's important to achieve at least a basic understanding. I'm no scientest, but I know if i drench something in vinegar AND keep it in the fridge, it's not going to kill me! If it's moldy, you'll be able to see it.
If the gun only has one bullet out of six chambers, don't pull the trigger.......AND, don't wonder IF that's the one jar of canned goods with botulism in it.

Someitmes I'll wing it (vinegar, fruits), mostly not! What's WRONG with using the most recent information. It's not like anyone is asking us to go out and buy million dollar equipment to do this....just follow reccomended times and procedures that have the benefit of being tested (on someone or something besides ME). It's too easy.

Thanks for letting me borrow your soapbox, Carol. Passing along to who ever needs it next! (BIG, FAT, GRIN).

Deanna

I read in the paper today that a man who possibly ate that recalled food with botulism is paralysed, except he can wiggle his toes. This shocked me, because I always thought badly processed food made you sick by throwing up.
Everyone says "it's dangerous", but is there is list somewhere of what can grow in food that's not processed correctly and what these things can do to you?
Carla in Sac

I've linked below to one source that gives a brief overview of the various bacteria associated with food poisoning. Of course that applies not just to home-canned foods but fresh meats, dairy products, etc.

Maybe people got sick or died in the past and no one thought of food poisoning as the cause.

Maybe they were stronger than we are today; those who survived (didn't die prior to the age of five) may have developed forms of resistance by exposure to many bacteria we no longer encounter. (Some scientists have speculated our children have lost certain immunities because we are "too clean," which may account for higher rates of allergies, etc.)

Maybe bacteria have just developed; it's easy to forget that bacteria are not static. Think how new stronger antibiotic-resistant strains of bacteria are making it more and more challenging for doctors to treat some of the infections people get. Whatever few bacteria survive antibiotics will live to breed a new stronger generation of poisons. The law of nature is survival. The question now is whether we can develop new treatments faster than the bacteria can mutate.

Maybe it's all of those things. All I know is it's better not to take any unnecessary risks (what Deanna called Russian Roulette). Doctors and hospitals aren't infallible and I'd rather not depend on them to cure me. It's easier to avoid the problem in the first place.

Actually, I think our best chance to eat well and stay healthy is to process our own food, following the best and most current information available to us. We've certainly seen in the media lately lots of examples of problems with the commercial food chain.

Food is strongly connected to our emotions and sense of ourselves. We all cherish family recipes and the rituals of food-preparation we remember. But it's no sin to update the approach, recognizing that conditions change. It needn't alter our affection for the parent or grandparent who first taught us and it isn't rejection.

Carol

Here is a link that might be useful: Historical Overview of Key Issues in Food Safety

Is there a source that gives general ratios of low acid to high acid? For example, there is a general ratio of flour to fat for white sauce, but I have not seen anything that would allow me to do calculations in my head when reading a canning recipe to know that its a safe one. I think this woould really help when reading recipes. Can anyone help?

I think there are too many other factors like density, combinations of ingredients, variables even in ph based on the health of the plant or type of soil. the "guidelines" that are published are WELL tested and nearly "Liability Free"! LOL
If it were as simple as a ratio, we'd be able to can pumpkin........ :+(
Deanna

Deanna

Hi all. Ran across this thread while looking for other information and thought I would ask a question that has been niggling at me. Now, I'm all about technology, my job depends on it, but sometimes one has to think about the old rule of working smarter, not harder.

My observation involves high acid foods and pickling in vinagars. It appears to me that if no amount of boiling will kill the botulism spores, so therefore acid must be added when using the waterbath method, what then is the point of the water bath method on high acid foods or those with added acid? If it is the acid that keeps the monster tame, not the boiling, why not use the open kettle method with pickles and high acid foods?

It seems to me that it is a non-value added step that is just stuck in there to by people who are afraid of a sue-happy public (and rightfully so!)

Gads, I'm probably too tired today to be answering this.

In simple terms, a certain amount of contamination almost inevitably enters the product in the process of transferring food from kettle to jars. So even if the jars, implements, etc. are sterilized contaminant organisms can be there.

Since the seal formed with open-kettle canning isn't as strong, the temperatures achieved aren't as high (due to the thermal effect of boiling water) and the duration of heat application is brief (only the boiling time in the kettle) the odds of maintaining quality on the shelf are much less.

I hope this makes sense. In other words, if storage conditions are less than ideal (too cold, too hot, fluctuations of temp), open kettle canned seals will more likely fail. Regardless, since the seals aren't as strong, product deteriorates faster. Flavors don't hold, product oxidizes and turns brown, things mold.

So none of these things will kill you, but in terms of "value-added," open-kettle saves you a little time in the front end but can cost you in the back end with loss of product through potential spoilage or just because it's no longer appealing to eat.

This has been well-known for 50+ years, long-before a "sue-happy public" was an issue.

In addition, today new bacterial strains are continuing to develop and many canners are reducing sugars in their products, making the longevity and safety of open-kettle-canned products even more problematic than they used to be.

As far as acidity is concerned, botulism is resistant to heat and it's the heat that kills the toxins and spores. As I understand it, acid doesn't kill botulism. What acid does is reduce the resistance of botulism to heat, which is why the higher-acid the product, the less heat which needs to be applied (boiling water bath as opposed to pressure canner). So there is a correlation between heat and acidity. It's a partnership, not one or the other.

Acid does discourage spore activity during storage.

Carol

kay,

Technically, you are exactly correct. It is the acid that keeps you safe from bacteria, not the boiling. The acidic environment prevents bacteria from growing. However, it does not prevent mold and yeast from growing. In fact, molds and yeast thrive in the high acid environment. Boiling is hot enough to kill the mold and yeast, which is why a high acid food is safe when processed in a boiling water bath.

Ok, so why is a BWB recommended? It's because the guidelines are designed for two reasons: 1) safety and 2) thrift. Open kettle canning can result in a poor seal and after storage, moldy or rotting (fermenting from the yeast) food in your jars. These in general are unsightly, smelly, messy creatures, and wasteful because you can't eat the contents. You won't get sick, because it will be obvious that the food is spoiled and you would never eat it. To successfully open kettle can, you have to work fast. If you don't work fast, the food cools too much to give you a tight seal. Another point is that open kettle canning requires sterile jars. If your jars aren't sterilized in the BWB, then you have to sterilize them first, before you put your food in them. If you don't sterilize the jars, you run the risk of putting your cooked food into a jar that contains a mold or yeast that will grow happily, even though the seal is tight.

Open kettle canning is not recommended not because of safety, but because potentially you can have more waste. While your point about litigation is valid these days, I don't think that was the case in the days when a boiling water bath was recommended over the open kettle technique. Whether a BWB is a non-value added step depends on whether the individual can work fast with boiling hot food, and whether they want to add a separate step of sterilizing your jars. If one doesn't want to do either of those two things, then it's a question of whether one is willing to accept a higher percentage of jars that don't seal or seal poorly.

Petro

Carol,

Our posts crossed.

As far as acidity is concerned, botulism is resistant to heat and it's the heat that kills the toxins and spores. As I understand it, acid doesn't kill botulism. What acid does is reduce the resistance of botulism to heat, which is why the higher-acid the product, the less heat which needs to be applied (boiling water bath as opposed to pressure canner). So there is a correlation between heat and acidity. It's a partnership, not one or the other.

Acid does discourage spore activity during storage.

What's important here, is it's the toxin that kills, not the bacteria, the toxin that is created when spores reproduce. No toxin actually develops in an oxygen rich environment, because the spores don't reproduce. For the spores to develop you need a low acid, low oxygen environment, i.e. a sealed jar in storage. It's the acid that keeps you safe during storage.

Petro

It's good to see you online, Petro. You know a lot more about these issues than I do.

Carol