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Canned Tomatoes; check to make sure Calcium Chloride is NOT an ingrediant!!

  • r

What do you guys and girls think about Calcium Chloride? My vauge understanding of canning tomatoes is as follows: to be canned, whole tomatoes need some combinatin of citric acid and calcium chloride as preservatives. But from what I also understand, calcium chloride is there mainly to keep the tomatoes from turning mushy. I read somewhere that Italians do not care so much about the consistancy of their tomatoes as americans, so it is a much more common ingrediant for canned tomatoes for the US market. I cant be sure, but from my experiance, i notice that tomatoes with CC tend to be more metalic tasting or astringant. Since my sauses do not come out as good, I desperately look for canned tomatoes without CC.

To my dismay, I notice that more and more imported cans of tomatoes and even organic companies such as Muir products in whole foods are including Calcium Choloride. Perhaps i am wrong about my observation? Perhaps it is just luck, or even actualy the result of citric acid? Finaly, if anyone found any great canned tomatoes without this phenomena, do tell?


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  1. I don't know what Calcium Chloride does or not, but after reading your post I went to look at my box of Pomi tomatoes and this is what it says: Ingredients: Tomatoes.
    It comes in chopped and strained.

    5 Replies
    1. re: mickyme

      Just watched an episode of America's Test Kitchen where the taste test was canned tomatoes. Chris K and the testers *hated* Pomi. They said it did not taste tomato-y.

      1. re: pdxgastro

        I know that, but it's one of the instances where I think they are flat out wrong (this is isn't the only time that happens). ATK is vulnerable to taste expectations issues in their testing.

        What I know is this: the sauces I make with POMI are invariably better received than sauces I make with San Marzano DOP canned tomatoes. The only thing that's better is fresh plum tomatoes in a good (that is, sunny and not-too-wet) season.

        1. re: Karl S

          I agree, Karl. ATK expectations can definitely cloud their results. They "evaluated" chocolate chip cookies with the expectation that the best ones were crispy. I don't agree with that, so their evaluation is useless to me.

          I like POMI, but prefer to use fresh when possible.

          I've got about 9 San Marzano's ripening on a bush now - they were the first tomatoes to set in this dreadful year. I figure that'll be enough for a doll's serving of pasta.

          1. re: Karl S

            I find that ATK is wrong as often as right. Their brine is also far too heavy on salt and sugar.

          2. re: pdxgastro

            I'm guessing what they did was taste it straight out of the box (as opposed to use it in recipes). Lots of other brands have lots of salt, and Pomi is pure tomatoes. I love using pomi...and no BPA in the packaging is a big plus too.

        2. s
          Science Chick

          Calcium chloride is a harmless, natural form of calcium, a normal mineral in your diet.....just like table salt (sodium chloride), only with calcium instead of sodium. Most minerals we ingest (potassium, sodium, calcium, etc) are in either the chloride or phosphate salt form. It's just the way they occur in nature!

          If you eat any mineral fortified cereals, juices....or even milk, you are probably eating more calcium chloride than you'll find in the tomatoes. Check the nutrition label on the can, and see how much dietary calcium there is, compared to tomatoes without calcium chloride. My guess is that there is such a small amount, that it doesn't even count toward the daily calcium allowance (just a guess, though)! Harmless...although I suppose there is a chance it could effect the taste. If so, I haven't noticed personally.

          1 Reply
          1. re: Science Chick

            In Russia 10% solution of Calcium Chloride in a distilled water is a renown strong fast acting remedy for allergies famous for the absence of side effects, with the exception of very unpleasant flavor, so it is taken with a milk. There are also injection and IV application in serious cases.
            I am sure it is harmless in caned tomatoes, and since I never tested the taste well familiar to me, I guess it is a tiny amount.

          2. Hi,

            I'm not quite sure what you're getting worked up about Calcium Chloride. I think you are panicking over something which is based on supposition rather than fact.

            I preserve tomatoes in glass jars out of personal preference. To every quart of tomatoes, I add two tablespoons of lemon juice to increase the acidity of the tomatoes. The acidity level is important because low-acid (pH) foods cannot be safely water-bath processed. Tomatoes are on the edge but the lemon juice (or vinegar) raises the acidity to a safe level.

            Salt is purely optional when preserving tomatoes, it is present for taste only.

            A tomato's ability to maintain its structure has much to do with the variety your preserving. Plum tomatoes hold up very well. The additional of calcium chloride is not going to change how a tomato holds up under cooking or preserving.

            The metallic taste in your tomatoes may come from the lining of the can. I have seen the more expensive canned tomatoes have thin (painted?) layer on the can's interior to keep the acid from interacting with the tin. I have to admit to very rarely coming in contact with tomatoes I haven't canned myself in over a decade.


            4 Replies
            1. re: Cathy2

              My parents have been water-bath canning the tomatoes they grow for more than 50 years without adding acid and without any problems whatsoever with their product. I would not discourage anybody from adding acid to this already acid product, but its hardly necessary.

              1. re: jen kalb


                Based on your anecdotal information, you can choose to do whatever you want. I have linked below to the National Center for Home Food Preservation.

                The USDA canning guide insists on acidification because the pH of tomatoes has been found to be borderline safe/unsafe. The addition of the lemon juice or vinegar increases the level of acidification from borderline to safe.

                The University of Illinois grew heritage, common and "low acid" tomatoes in test plots throughout the state. They tested the resulting pH with some variability. Interestingly, some "low acid" had higher acidity than non-selected tomato plants. This test was done in other states as well. This collective research-based recommendation to add lemon juice or vinegar to tomatoes before canning was not lightly considered.


                Link: http://www.uga.edu/nchfp/how/can3_tom...

                1. re: Cathy2

                  On a slightly related note...olives in olive oil etc.

                  Link: http://cecalaveras.ucdavis.edu/vinega...

                  1. re: barleywino


                    I was once in Texas around the time of the olive harvest. I was very, very tempted to buy a lug to take home. If I had the resources I have today, i.e. the internet and chowhounds, then I would have bought them confident one way or another an acceptable process would be figured out.


            2. Try Escalon..no citric acid added..most canners add citric acid because it speeds up the canning process..citric acid adds to people getting heart burn..Escalon steems the peel off the tomatoe just like your grandma did..

              1 Reply
              1. re: kathy


                Lemon juice - vinegar - citric acid are added to bring tomatoes, which are boarderline acidic, to a safe level of acidity for processing.

                From a home canning perspective, acid or acidified foods can be water bath processed, which includes pickles and fruits. Non-acid vegetables and meats are processed by pressure canning. Non-acidified tomatoes should be pressure canned for food safety. Each process gobbles up time, citric makes it safer but not faster.


              2. It is indeed difficult to find canned tomatoes that do not contain calcium chloride or citric acid even with the imported brands at an Italian market. But I did find "Bella Terra from Racconto" brand at my local Italian grocery store that has neither calcium chloride nor citric acid. They are wonderful. You can really taste the difference. Maybe you can Google Racconto to see where you can find this brand. Worth the search.

                1 Reply
                1. re: erikalwong

                  My box of POMI brand tomatoes says "Ingredients: tomatoes" that's it.....love the Pomi!! You might want to check these out...I get them at Publix 26 ounces for about $1.60??? Forget what I paid last time....

                2. I haven't been successful in finding canned tomatoes with out added calcium in some form. It prevents the tomatoes from breaking down into sauce in the can, which isn't good if you're trying to turn canned tomatoes into sauce. I haven't noticed a difference in taste, it's just a texture thing.

                  1. With my experience Muir Glen canned tomatoes are some of the best I have had so I am not so sure CC is a problem.

                    1 Reply
                    1. re: DishDelish

                      It's because MG has a plastic coating inside the can to avoid the metallic taste mentioned above. Look inside the next time you open one.

                    2. I was under the impression calcium chloride was added to make the tomatoes hold their shape (as in diced canned). It would only concern me if I wanted to be sure tomatoes would collapse when cooked - as in a sauce.

                      1. actually, I would be more concerned about the BPA that is in the can liner which leaches into the tomatoes and seems to be a Not Good Thing for our endocrne system etc etc. So tomatoes either in glass or the Pom would be preferable.

                        4 Replies
                        1. re: rubrifolia

                          just thinking about all those horrible diseases that are unique to the Italian-American community makes shudder ....

                          1. re: rubrifolia

                            I've been concerned about the BPA in canned tomatoes for awhile but haven't found a suitable sub. I tried making sauce with the boxed Pomi tomatoes once and it was HORRIBLE. Just off tasting and nasty. No glass jarred tomatoes where I live. Canning on my own is not an option.

                            1. re: rubrifolia

                              not only BPA, but other chemicals can leach out of the plastic that have not yet been identified as harmful (after all, BPA was used for many, many years before it was identified as being harmful).

                              i just buy tomatoes that come in a glass jar.
                              Whole Foods carries them, and Gelson's carries tomato puree in a jar.

                            2. Canned have a lot of chemicals and preservatives. The more processed they are i.e. cut vs. whole, the more preservatives, salt and chemicals they have like calcium chloride they have which is a firming agent. This may explain the slightly chlorine flavor of some canned tomato brands.
                              If you don't have fresh available, look for canned organic whole tomatoes, that are made without a BPA lining or calcium chloride. Tin cans contain BPA which is an endcorine disruptor in the human body (which can wreak havoc on the human hormone system).

                              Eden Foods is now making canned organic tomatoes without the BPA lining.

                              Laura Klein - OrganicAuthority.com

                              1. The biggest factors in how good tomatoes taste is the variety of tomato grown and the maturity when it was picked. Canneries use commercially grown tomatoes, which are more durable but generally don't taste as good. This is the price we pay for convenience.

                                I use calcium chloride (sold often as Pickle Crisp) to make dill pickles, dill beans, and canned tomatoes. I have a degree in food science & human nutrition (from a real university) and I can only offer that I personally have no qualms about using the small amount of CaCl2 required in my canning. Please remember that many additives and preservatives improve the safety and quality of our food and make a variety of products available year round.

                                Cook's Illustrated did a taste test of canned tomatoes a while back. The judges preferred the tomatoes packed with calcium chloride, hands down. (The Italian brands didn't fare as well).

                                Definitely the brands who have a lined can (usually white) taste better: the acidity in the tomatoes themselves don't react with the can to cause off-tastes.

                                I purchased food in bulk for hospitals/nursing homes for several years and I can also tell you that the lower the price, the more awful the tomatoes tasted.

                                3 Replies
                                1. re: applgrl

                                  Would it be better if canneries used home grown tomatoes instead commercially grown ones? The sort of ones that are given away at church during the peak of the growing season? :)

                                  1. re: paulj

                                    the tasty ones are too tender. They'd be moldy mush by the time they got to the processing plant. Sigh. You can't have everything.......best to grow a planter or two of your own every summer to enjoy real fresh tomatoes. Even when I can my own tomatoes and salsa, the sweet eating varieties can turn bitter and awful after cooking.

                                    1. re: paulj

                                      I've grown heirloom tomatoes for years, and while I love their taste, they are very poor choices for processing. In many cases, the skins are so thin that they will become bruised just from be placed on a table for a few days. You simply can't ship tomatoes like that from the field to the factory, much less process them. Sure, you can ship unripe ones and later use ethylene gas to ripen them, but that sort of defeats the whole purpose.

                                  2. You might want to try rinsing your tomatoes and throwing away the liquid that comes in the can. Ever since Alton told me to remove the seeds to reduce bitterness, I've been rinsing just to help with the seed removal process but I always included the strained juices in my sauces.
                                    Recently I saw a pizza sauce webpage that suggested that in addition to removing the seeds, not using the juice would also improve any brand of canned tomatoes. Could be my imagination, but after trying it, I have to agree.

                                    1. calcium chloride keeps the tomatoes firm and makes them taste "better", which is why Italian canned tomatoes don't use it, because when you cook them, you get more of the tomato flavor. give both a try in a recipe and then decide. out of the can the calcium chloride tomatoes will obviously have more flavor, but in a dish cooked the natural ones taste better. also, some tomatoes have just thin liquid and some are packed in puree or thick juice. cento tomatoes give higher yield and I wouldn't dream of not using the juice, unless you are using USA packed tomatoes, especially the horrible ones with sugar added

                                      1. It's just another thing I am not going to be afraid of like HFCS and MSG and oh my God, non-organic food!. I have bigger fish to fry like charging rhinos and exploding rubber chickens!

                                        1 Reply
                                        1. re: LorenM

                                          Exploding chickens!?!?! Where??? (Hits the ground).

                                          Agree entirely. This is just a new thing to be afraid of.

                                        2. I usually use DOP certified San Marzano tomatoes, and to my knowledge, they don't use calcium chloride, at least not the Cento brand which is what I use. However, I don't always feel it necessary to spend 5 bucks a can in order to make the very best sauce every time, so I will use an organically grown domestic product like Muir Glen or Red Pack for half the price. Both make acceptably good sauces. I simply rinse them and then soak them in water for 20 minutes to get rid of the calcium chloride taste which makes them overly acidic and metallic tasting.

                                          1 Reply
                                          1. re: IDavis

                                            Isn't it possible that the metal can is making them metallic tasting?

                                          2. This link explains both of these substances. Funny how you can use the calcium chloride in mixing cement and canning tomatos and makeing cheese!! http://www.quora.com/How-long-can-you...

                                            1. "Canned Whole Tomatoes" from Cook's Illustrated:


                                              Calcium chloride is a salt, and has the advantage over sodium chloride (table salt) of not contining sodium, which some people must reduce in their diet.

                                              My Strianese San Marzano tomatoes are described as containing "salt" without specifying which kind.

                                              2 Replies
                                              1. re: GH1618

                                                If it doesn't say I'm pretty sure it's required to be sodium chloride.

                                                1. re: Puffin3

                                                  Not at all. I never click over to youtube without a synopsis of the clip being offered. All to often it's oddly biased and/or low quality information.

                                                  1. re: Enso

                                                    you mean that you didn't like the honey badger youtube clip?

                                                2. Calcium chloride taste like bleach. Yuck. I always read the labels. Sadly most canned tomatoes have CC. Too bad. One has to really search for a good Italian market and even they're starting to use it.. Must be for us Americans. I loath CC.

                                                  1. muir glen foods is owned by General Mills.
                                                    draw your own conclusions.

                                                    2 Replies
                                                    1. re: westsidegal

                                                      not picking on you, westsidegal -- but this thread is quickly approaching its 10th anniversary....

                                                      Might still be a concern, but there might also have been significant changes....

                                                      1. re: sunshine842

                                                        hadn't noticed the date.
                                                        thanks for pointing it out.
                                                        maybe General Mills bought Muir Glen after the original post.

                                                    2. This one of the by-products made by the over-refining of corn. I notice this as I am very allergic to corn. As Monsanto loses out in the global market (more and more countries refuse to allow any of their GMO products in) they have to force their product into products that have never had it. Take citric acid and ascorbic acid as an example. In this country they are mainly derived from corn as it is cheaper than citrus fruits. Until this year I could drink Dole juices, now I cannot as they add Vitamin C to their Orange juice based beverages! Monsanto has said they cannot "afford" to let one dollar be spent on food in this country that is spent in part on their product.
                                                      If the calcium chloride in our food was sourced from limestone, you don't have the metallic taste. In addition you don't have the added risk of stomach cancer caused by many of the by-products of over processing our food, ie:caramel color.

                                                      1 Reply
                                                      1. re: Cimmi

                                                        There's nothing new about production of citric acid by a fermentation process (from a sugary solution, which could be corn based). That process was developed in 1920s.


                                                        Production of ascorbic acid by fermentation of a glucose solution is nearly as old. Most of the production comes from China.

                                                      2. since muir glen is owned by general mills, i fully expect them to contain whatever general mills normally adds.

                                                        1. I use compliments organic tomatoes. It has no CC.

                                                          1. Now here's a thing. One of my favourite dishes involves, amongst other things, cooking potatoes with tomatoes. In the summer, using fresh toms, no problem, the potatoes cooked in around 30 minutes. In the winter however using tinned chopped tomatoes resulted in the potatoes taking an age to cook - I mean, after an hour and a half they were still firm.
                                                            So checking the ingredients, I came across the inclusion of calcium salts - as mentioned elsewhere in this thread, this is added to stop the tomatoes turning into a mush during the canning process. It does so by stiffening up the tomatoes' cell walls. The conclusion I came to was that the calcium salts were also stiffening the cell walls of the potatoes.
                                                            To prove the point, I bought a tinned of pulped tomatoes where the canner had no need to add cost to his product and so, naturally, didn't add these salts. The pototoes cooked fine and within the expected time.
                                                            The disturbing thing is that in France, some cans of chopped tomatoes do not show on the label that calcium salts have been added, tho' they definitely have been, as rock hard potatoes are testament.
                                                            Walter Gunn - cookery writer and author of 'A Slice of the Pyrenees' and 'The Snail Cookbook'.

                                                            3 Replies
                                                            1. re: waltergunn

                                                              Cooking the potatoes separately (till partly done) should handle this problem.


                                                              acidity also lengthens cooking time.

                                                              Sodium bicarb on the other hand shortens it. Potentially it counters both the acidity and calcium salts.

                                                              Bean cookery faces the same issues. Hard water (with calcium salts) lengths the cooking time for beans.

                                                              1. re: paulj

                                                                Thanks paulj... We have tried part cooking the potatoes, and depending how far you go, this does do the job. This however turns a one-pot into a more-than-one-pot dish - something I try to avoid. Also, pre-cooking does not address the flavour issue - definitely bleachy. Apart from these issues, there's the disturbing point that an additive, no matter how safe, not fully described on the label can enter our diets by stealth.

                                                                Walter Gunn - cookery writer and author of 'A Slice of the Pyrenees' and 'The Snail Cookbook'

                                                                1. re: waltergunn

                                                                  Calcium chloride is E509.

                                                                  describes it as having a 'salty taste'.

                                                                  I can't confirm that, since the calcium salt in my 'Kit de cuisine moleculaire' is calcium lactate (E327), which is nearly flavorless (just slightly salty).