Is this going against current recommended procedures?

Yes, I'm sorry but it is. The guidelines for several years now read as follows:

Acidification: To ensure safe acidity in whole, crushed, or juiced tomatoes, add two tablespoons of bottled lemon juice or 1/2 teaspoon of citric acid per quart of tomatoes. For pints, use one tablespoon bottled lemon juice or 1/4 teaspoon citric acid. Acid can be added directly to the jars before filling with product. Add sugar to offset acid taste, if desired. Four tablespoons of a 5 percent acidity vinegar per quart may be used instead of lemon juice or citric acid. However, vinegar may cause undesirable flavor changes.

The variety of tomato makes no difference as far as the guidelines are concerned. All tomatoes are considered low-acid.

Pureed tomatoes raises other potential problems. There are instructions for crushed, whole, or halved tomatoes. However, if by "pureed" you mean tomato sauce then while the same acidification requirements apply, the processing time will be different.

You can find all the details and instructions as well as the current guidelines at NCHFP, the recognized authority on safe home canning. I linked it below.

Dave

PS: and welcome to the forum too!!! :)

Here is a link that might be useful: NCHFP

No by pureed I mean tomato juice that is boiled for hours until it is reduced by almost half. I just canned 45 quarts of tomato juice done this way with one tablespoon of white vinegar per quart, BWB for approx. 1 hour. This is the method my books, "Putting Food By", and "Stocking Up" recommended, which I've been following for the past 30+ years.

tomato juice that is boiled for hours until it is reduced by almost half.

Ok, that is called tomato "sauce" by most. ;)

Both of the books you list are considered very outdated as there have been several revisions in the safety guidelines since they were published. Both books have a "use only with care" from certified instructors and experienced canners.

I would recommend investing in a current copy of the Ball Blue Book for about $6.00 or, as I mentioned above, for all the basic instructions and recipes, you need only go to NCHFP. I linked the instructions for Tomato Sauce below.

Dave

Here is a link that might be useful: Canning Tomato Sauce

judydel,

Many people, like you, have canned tomatoes with adding only a little acid or even no acid for many years and have never had a problem.

Tomatoes are right on the borderline of being acidic enough to be sure to kill any botulism spores that might end up in them. So usually it's fine, unless folks use particularly low-acid tomatoes.

Botulism is rarely found in tomatoes, and even if it is, your canned tomato sauce is probably acidic enough to kill it, especially with the bit of acid you've added, which was the recommended amount for many years.

I personally would happily eat your tomato sauce (definitely sounds thicker than juice to me!) because the CHANCES of it not being safe are small.

But.... Dave is right that the recommendations have changed to call for adding more acid. The reason is that you can't tell, at home, for SURE how acidic your tomato products are; sometimes the kind of soil, the weather, how ripe they are, etc. can affect them, and it's possible to get some that are not quite acidic enough to kill botulism for sure. AND... while botulism is rare, it's VERY dangerous --- often fatal --- and it happens to grow in vacuum environments like canned goods, if they aren't acidic enough --- and there's NO WAY to tell if it's in your cans, because it's odoourless and tasteless and invisible.

So the latest recommendations are forumlated for guaranteed safety. A lot of people prefer to go with the guarantee rather than the "only a small chance of a problem."

To follow the latest regs and be perfectly sure of being safe, you need to add more acid than you've been doing.

The recommendation is four tablespoons of vinegar for a quart.

IF you use lemon juice, you can use only two tablespoons because it's a stronger acid (bottled lemon juice is recommended rather than fresh, because its acidity level is known).

You can also buy citric acid, which is really concentrated and has almost no flavour, and use only a half teaspoon.

Welcome to the forum! Isn't home-canned tomato sauce a wonderful thing?

Cheers,

Z

Z thanks so much for taking the time to write. I wonder if I can do anything at this point to be sure that these 45 jars of sauce are safe? For instance, could I pressure cook the tomato puree before making my sauces? I used Speckled Roma and Heinz tomatoes. I'll try and find the seed packets and see if they list the ph levels, realizing of course that environmental considerations could change the actual ph. I wonder if pressure cooking for a certain amount of time would kill botulism if there is any present?

The seed packets won't list pH levels and it's irrelevant anyway as pH levels can vary considerably even within the same variety depending upon seasonal growing conditions, degree of ripeness and overall health of the plant.

The only fail-safe way is to follow current recommendations. Keep in mind that old-timers often used vinegars which were much stronger than the 5% available today, so many of those old methods just don't "translate" for a lot reasons.

You can bring your tomato sauce to a hard boil and boil for 10 minutes before using in a recipe and that will kill any active toxins. Like Zabby, I don't believe there's much risk, if any, but it is a comfort thing to follow that measure.

Carol

Ah, Carol I should have known you'd come in with that old Amish method. I thought it'd be effective, but couldn't find anything in print (I think of on line as print) and was hesitant to give questionable advice.
kay

Ladies thanks so much!! I also found a website that said food contaminated with botulism could be boiled for 30 minutes to render it safe. These jars of tomato puree will be used to make pasta sauce and will surely be boiled for at least an hour before consuming . . . so I'm not worried. Of course, if I open a jar and it has an odor or if the top is bulging or if there is mold growing, etc. I'll dispose of carefully. But if the tomato puree looks normal and smells normal, then I'll boil it for an hour or two and then manga!

But from now on I'll can my tomatoes using the recommended amount of ascorbic acid! I am SUCH A FANATIC when I can tomatoes or anything. I practically kick my family out of the house for the day. I make the dog stay outside for hours before I get to the canning part . . . the cat gets shut away in his room. I clean the whole house first unless it's already freshly cleaned. I definitely clean the kitchen. I sanitize every thing I use when canning and keep an ample supply of boiling water on hand. And I usually process the jars for 10 or 15 minutes more than the charts say, just to be extra safe. My family thinks I'm nuts, lol. So it's kinda funny that this happened to me. I just kept on going with the old standards and never realized they got updated. Oh well, we survived!

But from now on I'll can my tomatoes using the recommended amount of ascorbic acid!

Judy - please note that is not ascorbic acid that is required. Lemon juice or CITRIC acid - different things. ;)

Dave

You'll be fine. I really don't think the risk is high but using the sauce in a long-cooked recipe is definitely the best.

Do keep in mind (not trying to scare you here) that unlike other forms of spoilage like flat-sour, botulism is undetectable by sight or smell. Lids don't bulge, nothing seems "off," so those standard measures just don't work in this instance.

Carol

Dave thanks for the correction. I have ascorbic acid for dipping apples, etc. I'll have to look for citric acid for next summer.

Carol that's what I've always read . . . but the site I found that gave a long description of botulism and the different kinds (I wish I book marked it) talked about some types giving off odors, spurting, etc. So it's confusing.

Mrs. Wages Citric Acid is also sold in stores with the canning supplies. Usually right next to the Mrs. Wages pickling mixes on the shelf. It is also available online in bulk form from several different sources including bulkfoods.com.

Carol is quite correct about botulism. The c. botulinum spores themselves may smell in certain lab conditions, the toxin they produce does not. And in home canning it is the toxin that is lethal, not the spores themselves, so you cannot count on smell, taste, or color as a clue to its presence. Hope that eliminates the confusion for you.

Dave