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Sep 12, 2012 11:00 AM

Canning tomatoes and I don't have citric acid

I don't want to use bottled lemon juice (I would use fresh). I do have "Fruit Fresh" on hand (because I thought I might be able to use it). Don't know if it's safe, though. The product contains both citric and ascorbic acid, as well as dextrose and an anti-caking ingredient. Has anyone used this for canning?

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  1. Bottled lemon juice is used for canning because the acidity is controlled, which is the whole point of adding lemon juice.

    1. I have never used anything but bottled lemon juice and the results are always perfect (I usually follow an old Ball Jar canning guide). Exactly what GH1618 said: bottled lemon juice is used for canning because the acidity is controlled, and the USDA recommends bottled lemon juice for this reason. You probably could use fresh lemon juice if the lemons were sour enough, but it's a risk so you have to weigh your option. Personally, I'd just as soon not ruin my gorgeous canned garden tomatoes (and all that work) or get/give food poisoning, and I stick to USDA and/or similar (like university agriculture department) guidelines.

      I've never seen Fruit Fresh (the Ball product) recommended for canning tomatoes; it is designed for FRESH fruit, not canned.

      Here is a short explanation about lemon juice in preserving tomatoes from a blog devoted entirely to canning:

      And here is a great PDF explaining PH balance in tomato canning:

      4 Replies
      1. re: team_cake

        Ok I've decided to roast half of the tomatoes for freezing today and can the rest tomorrow when I get citric acid. Yeah, don't really want to poison anyone. I think I can find citric acid at a large drug store (our local one doesn't carry it).

        1. re: Nyleve

          check with all the other canning stuff at your whatever-mart monster store.

          they should have what must be enough for YEARS of tomatoes for ~3 dollars. same brand as the jars, lids what have you.

          1. re: j8715

            I'm in Canada. We don't always have normal stuff here. Abnormal, however, is easy to find.

            1. re: Nyleve

              A coupla seasons ago, I went (last minute) to a brewers/winemaking store and paid something like $10 for a tiny baggie (I dunno, maybe 28 grams - it felt more like a drug deal...).
              Coupla months later, I was perusing the spice section of a Caribbean store. There was a 4oz bag of citric acid for $3. I was both happy and pissed; the home wine making store is selling @ $10/oz (and it was bought in bulk and broken down by the store) when this place was selling for about 75c/oz! I bought 4 bags and put them with my canning stuff.
              Maybe check out a well stocked caribbean store (I live near Montreal).

      2. I found citric acid in a properly stocked drug store. Had to ask for it at the prescription desk! There was none at any of the regular places that sell canning supplies. Sheesh. Oh well - tomorrow I do the tomatoes.

        11 Replies
          1. re: porker

            Just wondering how crucial the bottled lemon juice is. I just canned some tomatoes which I have done for years, heard the lids pop, everything seemed fine. Now a week later they are bubbling and hissing and there is a pool of liquid at the bottom of the jar and it looks like the tomatoes have floated to the top.

            Are they safe to eat and is it because I used fresh lemon juice and not bottled? Thanks, Liz.

            1. re: albanis

              Similar questions always pop up (Is it safe to eat, what caused it, etc) and I don't think anyone can definitively answer one way or another. Except maybe to have the stuff tested by a lab and having a qualified person interpret the results.....

              What I do know is that tomatoes are generally on the fence when it comes to canning: they're not quite acid enough (nor basic enough) to can safely 100% of the time. Some years/some batches/some strains of tomatoes might be just acid enough allowing for canned storage without the lemon juice/citric acid. Some years/batches/strains, they might not be acid enough - its not an exact science.
              The use of citric acid (or lemon juice) generally makes it safe regardless of the tomato.
              Of course there are other possible problems inherent with canning besides the acid level, sterilization likely being most important....

              1. re: porker

                Tomatoes are only on the fence when it comes to hot water bath canning. You can always pressure can them, and then you don't have to worry about the acidity, and can can them without additives.

                It seems like with the resurgence of canning, we are seeing more people confused about what is safe to can, and the difference between pressure canning and hot water bath canning. And I'm finding that just a bit scary.

                1. re: MelMM

                  Most people aren't going to invest in a pressure canner unless they plan to do a LOT of canning. I have been canning for decades but still don't have a pressure canner - which is probably silly, but there you go. I know tomatoes are on the fence, and in the bad old days I just canned them, and even tomato sauce made with a mixture of vegetables, without a second thought to the safety of it. I didn't die. But I'm much more cautious now and prefer some degree of safety. I read the various guidelines and decided to go with something in the mushy middle - 1 tsp. citric acid per quart and 45 minutes in the water bath canner. Not entirely up to code, but much better than what I used to do. I balanced the potential flavour intereference of the citric acid with a tsp. of sugar per jar. Will let you know how it turned out when I open my first jar - probably not before November.

                2. re: porker

                  Actually, it is "an exact science" in that, its simply a matter of acidity. And acidity, is simply a matter of PH. and PH is simply a matter of measuring the PH, and determining whether it is within appropriate ranges. So, im pretty sure that falls under the definition of "exact science", since its exact, and it involves science.

                  and the lab or "professionals" that you would entrust to tell you so much information about your tomatoes, would stick a sensor into it and tell you the PH, and thats it. Or you could spend anywhere from $10 - $10,000 on a tester of your own. Then you too could determine how acidic your tomato puree/sauce/whatthehelleverelse, is. Magical.

                  1. re: albanis

                    Tomatoes floating to the top is normal. Your seal sounds like it was fine. But the hissing and bubbling is NOT normal. Nor is it a sign of botulism - which doesn't actually announce itself by bubbling and hissing but sits there in the jar quietly waiting to poison someone. I don't think it had anything to do with the lemon juice but I suspect it was some other issue. Maybe some other bacterial contamination - jars not boiled long enough would be my guess. I wouldn't eat those tomatoes - and believe me, I eat almost anything.

                    1. re: Nyleve

                      Okay, it's quite possible they were not processed long enough. I also did not have them standing up in the water bath. In the past I did this and I don't think it mattered but I was also incredibly sleep deprived when I did it so I was rushing through them. I'll toss them. Makes me sad but I don't want to take the chance. Thanks!

                      1. re: albanis

                        I hate throwing stuff out but this sounds just a tad too far gone.

                        On a happier note, I've been canning my tomatoes all afternoon. I have the second batch in the canner right now - the first batch is cooling on the counter. Very happy about this. I bought a bushel of romas and roasted and froze half of them, canned the other half. I am ready for the apocalypse!

                  2. re: porker

                    It was around $5-ish for a 100 g container.

                3. I just canned tomato sauce for the first time because my tomato plants were especially prolific this year.

                  Does anyone have any other uses for citric acid? I tried adding a bit to pesto to keep it from turning that nasty dark green (dubious results).

                  1 Reply
                  1. re: j8715

                    Citric acid can be snuck into sausage recipes to give that long-cured/fermented flavor. Try adding a sprinkle over green beans, cukes, carrots- things that taste good pickled! Swirl a teaspoon into a glass of water and pretend its crystal OJ!

                  2. I have never added citric acid when canning any tomato product. What am I missing?

                    14 Replies
                    1. re: John E.

                      Nor have I. ~ Have canned tomatoes (Hot water bath) for 50+ years, and never used any additional acidic product.

                      1. re: John E.

                        What you are missing is the safety margin against botulism provided by an assured level of acidity.

                        1. re: GH1618

                          Guess I've been missing it for over 50 years. My mother missed it for 50 years prior to that. My grandmother for 75 years prior to that. My great grandmother........ Maybe I should play the lottery.

                          1. re: Uncle Bob

                            Your analysis is unsound. All good safety protocols have redundancy. It is prudent to have a comfortable margin of safety in any potentially dangerous activity. Most people get away with risky behavior, but a few do not.

                            1. re: GH1618

                              In this case, it's so easy to create that safety margin, I can't see any reason not to do it. A package of citric acid is cheap and will last forever. I used to do without, but I'm now a convert. I add a tsp. of sugar to every jar of tomatoes to offset any flavour change from the acidity, but honestly don't think it's even necessary. I get that grandma did it for years and no one died. But who wants to be the one-in-a-million exception?

                              1. re: GH1618

                                Yep. It's a wonder that mankind hasn't died off. And with all the carcinogens in grilled meats it's a damn miracle that the species is not extinct. Tort reform would go along way dispelling this type of BS.

                                1. re: Uncle Bob

                                  We choose our risks. I'm not willing to give up grilled meat, but I can increase the acidity in canned tomatoes easily. No big deal. I'm no germophobe by any stretch of the imagination but I don't actually think this is BS.

                                  1. re: Nyleve

                                    Maybe just plain old horse shit then. :))

                                    Have fun!

                                  2. re: Uncle Bob

                                    Mankind will survive quite a lot. It's individuals who sometimes die when things go awry. Not a problem unless the individual is you or someone close to you, I suppose.

                                    1. re: GH1618

                                      "Mankind will survive quite a lot. It's individuals who sometimes die when things go awry"

                                      I like that...makes me feel good with the odds and all - 7 billion to one?

                            2. re: John E.

                              Various hybrid tomatoes have been developed with reduced acidity (i.e., for flavor reasons). There is a risk of botulinum bacteria, the cause of botulism, in foods which are low acid. Adding the measured amount of citric acid to your canned tomatoes ensures the minimum acidity required to reduce the risk of food borne illness in tomatoes which are water-bath processed.

                              1. re: KarenDW

                                That's why my mom and dad never canned the low-acid yellow tomatoes when I was a kid.