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Sep 9, 2013 06:17 PM

Sealing Canned Tomatoes in a Hot Canning Bath

OK, so I canned my tomatoes today with half pint jars! It was a lot of work and about 3 hours of my day to do, but think I did it! Just one nagging issue I'm having with them: My jars kept floating to the surface in the tallest pot we have for the final hot water bath, so while the lids were not completely submerged, they still look like they were vacuum sealed after soaking in boiling water with the lid on the pot for about 45 minutes. Are they safe to eat, or will we get botulism poisoning? My husband, who is a great cook in his own right, says I shouldn't worry since his mother and grandmother also canned tomatoes and the finished product resembles theirs (he's a true gent!), and he also says that because I put the cover on the pot, it was the steam and the heat that helped seal the lids on the jars, but I just need a little extra reassurance! I would hate to see all my time and work go to waste, but better that than getting myself or someone else sick. Thanks!

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  1. Did you follow any instructions for canning the tomatoes? (Time seems pretty short...)
    Was the method hot pack or raw (cold) pack?
    Did you add citric acid to make them acid enough to be water-bath rather than pressure canned?

    If raw-pack, I think no; if hot pack, and acidified, maybe OK. The jars are really supposed to be covered with water. Me, I would freeze them or refrigerate and use them. Canning is one of those 'when in doubt..." sports.

    Please see this site

    for more information on canning tomatoes -- I have never canned half-pints, only pints and quarts.

    My constant advice to new canners is to always find and follow instructions from a .edu or .gov site for canning guidelines. Or the Ball Blue Book.

    1 Reply
    1. re: DebinIndiana

      Thanks so much! Yes, my husband is reading that same website and we're going through it together!

      I added 1 tablespoon of lemon juice into each jar, and I followed the hot pack method. I think next time I will just use pint jars, or even go ahead and purchase a pressure canner that has a built-in rack to submerge the jars completely.

    2. I know all the current advisories for canning and I follow them now but I grew up eating home canned foods and I canned my own tomatoes back when we simply freshpacked them from the garden without added acid so I have a degree of confidence that most probably don't to accompany my healthy respect for the reasons we work on good sanitation.

      What I would do in your case is take the rings off the jars and see if you can lift the weight of the jars by just the flat lid. If you can you got a seal.

      Now, when you open a jar feel the lids to make sure you can detect the depression in the lid. Open the jar and make sure you don't see anything discolored or bubbly or smell anything suspicious. If you do, dump it. If anything makes you feel less than confident, dump it.

      Then make sure you heat the tomatoes adequately in whatever you're preparing because you don't always smell or see problematical toxins.

      Next time, make sure you fill the jars to the recommended head space. They should be heavy enough to stay submerged in the pot (I'm curious why yours were able to float). Use a pot that's deep enough to cover the lids by 1". And process for the recommended time. But also remember that I got to be 65 eating tomatoes that weren't water bathed at all and tomatoes that had onions, celery and peppers added further reducing the acid for years.

      1 Reply
      1. re: rainey

        I'm wondering the same thing- how did those jars float? If they were full to 1/8 or 1/4 inch, they should have simply displace the water and stayed submerged.
        As others have said, use recommended canning procedures. Your state agricultural university should have recipes on their website.

      2. I've never had jars float: floating means the jars and contents are less dense than water, which to me means you have a lot of air in them. Removing the heated air is what causes a partial vacuum to form in the jar, creating the seal.

        One quick test: when you took them out of the water bath, were the lids slightly depressed in the center? This generally means a good seal. If there's some give when you press lightly on the lids, they didn't seal correctly, and should be used immediately. Covering the pot doesn't make any difference if you're doing hot water canning: the temperature's not going to get above the boiling point of water anyway (pressure canning is another thing altogether)

        What kind of tomatoes did you use? Older varieties are more acidic, and can be canned more reliably in a hot water bath: less acidic varieties need additional acid (vinegar, lemon juice) to bring their pH down to a level that won't promote bacterial growth. (It's unlikely that you'll come down with botulism poisoning since that's usually a soil-borne contaminant, but there are other microbial nasties lurking that can contaminate poorly processed tomatoes.)

        ETA: Elevation makes a difference. I live roughly at sea level, so my water boils at 212F. If you're in Denver or Albuquerque, you have a lower boiling point so longer processing may be necessary. Again, check with Ball or the USDA for guidelines.

        I can be pretty cavalier about a lot of things in the kitchen, but when it comes to canning I read the instructions - no matter how many times I've done it - and follow them to the letter. The Ball website is a good place to start.

        1. I never did half-pints either; I'm thinking you may not have released all the air. As others have responded, as long as you have a tight seal, you should be OK. I think 45 min. is way too long to process half pints, but if the jars were floating, I'm thinking that made you nervous? Just curious, how much did you start with, and how many half-pints did it yield?

          7 Replies
          1. re: dberg1313

            Thank you everybody for all of your replies! To answer a few of your questions first:

            @rainey: You're absolutely right about following the practices which change so much over the years. Canning has existed for so long, and I know my mother-in-law and my grandmother-in-law during their generations certainly followed other practices of the day without knowing today's guidelines. I used 1 tablespoon of lemon juice in each jar. I used 4 jars and I know I only really filled 2 up to the top with 1/2 in. headspace...the two other jars I left substantially more headspace (oops) and I didn't use a thin spatula to wipe out any potential air bubbles (double oops) which led to one of my four jars skimming the surface of the boiling water bath during the sealing process.

            @tardigrade: The tomatoes I used for this were biggest, reddest, fattest tomatoes I could find from a farmer's market. And yes, the seals are concave and don't make that clicking sound when I tap the center of the lid with my finger. So they must be sealed and safe to eat (I hope!).

            @dberg1313: Yes, I think I was nervous. There were so many steps--not to mention so many variations of hot water pack canning recipes!--that I tried following the best ones I could to a T, and I was nervous during the sealing step since I thought I was making good progress. I just know now I missed two crucial parts.

            So, I now see where I went wrong: First, I forgot to get rid of air bubbles with a thin spatula after stuffing the tomatoes in; second, I provided too much headspace in two of my jars. It takes so much trouble to sterilize the jars to begin with and my half-pinters took up so much space in our largest cooking pot that I did two jars at a time, and I figured I may as well use all four sterilized jars after all that trouble! Having a day off work and being forgetful is no excuse to cut corners with this practice :-/

            Even though I know what my mistakes were, I am still undeterred and want to try again so I can master tomato canning! Next time I will also likely just stick with pint jars instead. And even though we live at sea level I will leave the tomato-filled jars in the hot water bath for 85 minutes just to be safe, as per the USDA canning guidelines (, Guide 3, page 11).

            Tomato canning sure is a learning curve, isn't it? :-)

            1. re: rainstar17

              Sterilizing your jars shouldn't be so much of a problem. Run them through your dishwasher with the dying option on. It probably even has a "sanitize" setting. I also put my oven on 220˚ and put the jars in it on a baking sheet to hold the temperature if the dishwashing cycle is over before I'm ready to pack the jars. Put the lids and rings in a pot of simmering water.

              And 85 minutes of processing seems sorta insane. They must be mush by that point. 40-50 minutes should be plenty. Here are some good instructions with photos that I hope will be helpful:

              It sounds like the FDA might not fully approve but as I said earlier, I used to just quarter my tomatoes, pour over hot water, stick on a lid and wait for the jars to cool. Sounds scary now but I'm here to tell the tale and don't remember so much as a belly ache. ;>

              Actually, I just checked your reference and 85 minutes is for tomatoes packed in tomato juice. I've never done that so if you're using juice instead of just water I guess you're doing it right. Good for you!

              1. re: rainey

                Doesn't 85 minutes sound insane?! But I guess that's what they say so there you go. I don't have a dishwasher at my place unfortunately, so for me steps 1 and 2 were hand-washing my jars and lids with soap and water, followed by boiling them on the stove. The oven is a groovy idea too just to be extra sure that they are sanitary.

                On the other hand, if you think of Depression-era folk like my mother-in-law and her mother (both of whom recently passed away...I never got to ask them how they made it even though it was on my mind for years) who canned their tomatoes out of necessity without any new information on canning practices, and they survived off of those foods when there was little else to eat. It's good to be as careful as possible in these modern times, but still maybe I should cut myself a little slack for my first time (not the last time though!) :-)

                1. re: rainstar17

                  COMPLETELY cut yourself some slack and then congratulate yourself!

                  It's a brave thing to give this a whirl when you read about all the considerations! I'm not sure I'd start canning now if I hadn't when I was blissfully ignorant. ...except for what remarkable things my great aunt canned. ; >

                  Ready to try some jam or preserves? You can make yummy and very unique things and the natural acid and added sugar of jams and preserves make them much less susseptible to problems.

                  Good job, rainstar!

                  Oh, and I'm positive your hand washing is doing the sanitation job but you also want those jars hot so you avoid thermal shock when you fill them with hot contents. You can warm them up in a 220˚ oven after they're washed. I'd recommend it.

                  1. re: rainey

                    Sometimes ignorance can be bliss, right rainey? :-) Thank you so much! That's a great idea with the oven, especially to avoid thermal shock....I had never considered that. So hand wash, then oven, then boil? Or would boiling them not be necessary if they're going in the oven? Sorry for all these rookie questions!

                    Maybe jams and preserves or even some salsa might be next! I gotta say, even though canning takes a lot of work and time and care, it's also so rewarding and satisfying and fun! I'm sure the results will taste good too! :-)

                    1. re: rainstar17

                      Just let them rest in the oven after you've cleaned them and prior to filling them.

                      Yup! it's pretty exciting to open something you made yourself and still tastes like summer when all the really fresh produce is gone. You're doing a good thing! ; >

                      1. re: rainey

                        I simply put the jars in the canning pot to heat up with the water. I take them out as I fill each one or two, and put them right back in the boiling water. I never thought of doing it any other way!

          2. Looks like you got a lot of good advice, rainstar. I hope you will keep working on the canning project with the same enthusiasm and the good guidance from the USDA or other reliable source.
            I know that my grandma, who taught me how to "put up" food, was always willing to learn more. "Back in the day," we all took the best advice available, and we can all continue to learn.

            Beware, though, that I have seen some truly wacky and unsafe methods posted on the internet (not here!!), so pay attention to the reliability of your source.

            2 Replies
            1. re: DebinIndiana

              Hi everyone! Thank you all so much for your feedback! Here is my very first batch of tomatoes that I canned. You might notice that a couple are particularly low and weren't stuffed as much. I think that's why they were floating...those will be the first ones we consume! I'm about to do more canning with pint jars and more knowledge under my belt! Feel free to weigh in on how they look, good or bad! Thanks again!

              1. re: rainstar17

                Be sure to follow directions in a good (recent) canning book. That headspace should be no more than 1/8 to 1/4 inch!
                Kudos to you for the effort, next time will go much better- and you'll use fewer jars if you fill 'em up right!