Many home canners assume that white distilled vinegar is the most acidic ingredient in their arsenal.
Not so: lemon juice is actually even more acidic than white distilled vinegar.
pH of a few typical canning acids
Here’s a comparison in descending order of the pH of a few typical canning acids (remember, the lower the pH, the higher the acidity): [1] Source: FDA. Approximate pH of Foods and Food Products. April 2007. Accessed March 2015 at https://www.healthycanning.com/wp-content/uploads/pH-FDAapproximatepHoffoodslacf-phs.pdf.
- Apple cider vinegar: 3.10
- White distilled vinegar: 2.40 – 3.40
- Oranges (fresh): 3.3 – 4.34
- Lemon Juice (fresh): 2.00 – 2.60
- Lime Juice (fresh): 2.00 – 2.35
What does lemon juice do in home canning recipes?
The Putting Food By authors say this about lemon juice,
“Lemon juice contains both ascorbic and citric acids. Average acid-strength of fresh lemons is about 5 percent (also the labeled strength of reconstituted bottled lemon juice; some strains of California lemons are less strongly acidic, however). Being in solution naturally, it’s about one-sixth as effective volume for volume as ascorbic acid for preventing darkening. Even more of a flavor-masker than citric acid, it also adds a distinctive lemony taste to the food. It is used primarily to augment a food’s natural acidity.” [2] Hertzberg, Ruth; Greene, Janet; Vaughan, Beatrice (2010-05-25). Putting Food By: Fifth Edition (p. 36). Penguin Publishing Group. Kindle Edition.
Use bottled lemon juice
Beginning home canners are usually shocked to find that so many of the tested and approved home canning recipes call for bottled lemon juice.
The University of Georgia Extension Service explains why:
“Bottled lemon juice is used to standardize acidity. Fresh lemon juice can vary in acidity and is not recommended.” [3]E. M. D’Sa, E. L. Andress, J. A. Harrison and M. A. Harrison. 2006. Thermal Process Development to Ensure the Safety of a Home-Canned Lemon Curd Product. Athens, GA: The University of Georgia, Cooperative Extension Service. Accessed July 2016.
The Bernardin Guide (2013) says,
“Lemon juice – bottled juice is preferred because the commercial product has a standardized pH (acidity) level.” [4]Bernardin Guide to Home Preserving. Toronto, Canada: Bernardin Ltd. 2013. Page 48.
Fresh lemons can vary in acidity based on:
- variety (Meyer lemon juice is lower in acidity, with a pH of 2.6 compared to 2.0 to 2.6 for that from most other lemons) [5]: “The juice of the Meyer lemon contained more citric acid (3.5%) than juice of oranges (1.0%) but less than juice of commercial lemons (6.0%) (Birdsall et al., 1961). The pH of Meyer lemon juice (2.6) was somewhat higher than that for commercial lemons (2.3) and lower than that for oranges (3.0 – 4.0) (Kefford, 1959). As with oranges, the percentage of citric acid decreased with maturity of the fruit, whereas in lemons it increases.” — KENNEDY, B.M. and SCHELSTRAETE, M. (1965), Ascorbic Acid, Acidity, and Sugar in Meyer Lemons. Journal of Food Science, 30: 77-79. https://doi.org/10.1111/j.1365-2621.1965.tb00266.x [6]FDA. Approximate pH of Foods and Food Products. April 2007. Accessed August 2017 at http://www.vldhealth.org/pdf/environmentalPDF/foodPH2007.pdf ;
- where in the world the lemons have been grown;
- the weather during their growing season;
- how long they are in storage along the way, in the store, and in your fridge;
- storage conditions, etc.
Bottled lemon juice, however, is governed by Food and Drug Administration rules. It must have “a titratable acidity content of not less than 4.5 percent, by weight, calculated as anhydrous citrus acid.” [7] Code of Federal Regulations (Title 21, volume 2, revised April 1, 2010), via Linda Ziedrich.
Given the variables that can affect juice from a fresh lemon, and given that the acidity of the bottled lemon juice is a known, guaranteed factor by law, it’s no wonder that the canning authorities often play it safe and decide to settle on bottled to provide the critical safety margin in a recipe. Asian pears, figs and tomatoes require an acid such as lemon juice as a critical element to make them safe for canning.
The authorities weren’t going to rely on the wildcard of a “fresh lemon” for safety. Nor could they possibly begin to even dream of having the resources to monitor on a regular basis the acidity of new cultivars of lemons coming on the market all the time, impact of varying countries of origin and weather conditions on acidity, etc. They need to make recommendations that can last several decades at least, because they never know when the next few shekels of funding to review the recommendations will come along. So, by calling for commercial bottled, they can ensure that everyone is getting the same safe acidity level.
Acidity conclusion disputed
For the record, respected home canning author Linda Ziedrich disputes the USDA’s view on the assured acidity of fresh lemon juice versus bottled. You may wish to review her analysis at : Real Lemon versus ReaLemon (link valid as of March 2015.)
Bottled lemon juice has an expiry date
Don’t forget, bottled lemon juice has a best-before date. Keeping the product in the fridge should extend its best-before date greatly.
What bottled lemon juice swaps can you do?
Safety-wise summary: You can swap bottled lemon and lime juice interchangeably, and you can always replace vinegar with bottled lemon or lime juice. But you cannot ever do the reverse and replace either of those two with white vinegar, because it’s weaker than those two. Note that while lemon and lime juice are quite acidic, sadly orange and tangerine juice (with a ph of 3.30 – 4.19) are far less so and so cannot be swapped in as safety equivalents.
Angela Fraser at North Carolina Extension says,
Bottled lemon juice tends to be more acidic than vinegar. It also has less effect on the overall flavor of the product in which it is used. Equal amounts of bottled lemon juice can be substituted for vinegar in recipes calling for vinegar. Vinegar, however, should not be used when a recipe calls for lemon juice.” [8] Fraser, Angela. North Carolina State University Cooperative Extension. Celebrate with Safe Salsa. FCSW-516. Accessed March 2015 at https://www.ces.ncsu.edu/depts/fcs/pdfs/FCS516WAccessibleApril09.pdf.
You can also swap in citric acid in appropriate ratios (for instance, when doing tomatoes, which allow for either bottled lemon juice or citric acid.)
Suzanne Driessen at the University of Minnesota says, “You can safely use bottled lime juice instead of bottled lemon juice.” [9]Driessen, Suzanne. Canning Tomato and Tomato Products? Pay Attention to Directions. University of Minnesota Extension Service. Reviewed 2014. Accessed June 2016 at https://www.extension.umn.edu/food/food-safety/preserving/tomatoes-salsa/canning-tomato-and-tomato-products./
When you can use fresh lemon or lime juice
When a canning recipe calls for bottled lemon or lime juice, or just lemon or lime juice, use bottled, don’t substitute fresh.
If a tested recipe from a reputable source such as Ball or Bernardin labs test kitchens calls for fresh lemon or lime juice, go ahead and use that (though you may also use bottled if that is all you have to hand or if that is your preference.)
If a recipe calls for fresh lemon or lime juice, but you only have bottled you may use bottled.
Some canning authors say that whenever you are are sure that the safe acidity requirements are already met elsewhere in the recipe, you are free to use fresh lemon juice. For instance, home canning blogger Marisa McClellan says:
However, when it comes to recipes where the level of acidity isn’t crucial (for instance, when you’re adding lemon juice to a batch of jam to balance the sweetness), you can use fresh lemons.” [10] McClellan, Marisa. Canning in Vintage Jars. Blog posting: Some Canning Questions and Answers. December 2009. Accessed March 2015.
The issue with that advice, however, is that probably only .001% of home canners would have the knowledge of when a jam was acidic enough. Don’t forget: safety aside, high acidity in jams is also required (along with sugar) for traditional pectin to set to make the jam worth canning!
The Pacific Northwest Extension says that Meyer lemons or Key limes are less acidic:
Don’t use Meyer lemon juice or key lime juice, they are different, and weaker: “Key lime juice should not be used as lime juice.” [11] Salsa Recipes for Canning. Pacific Northwest Extension. PNW395. 2014. Page 4.
Ball’s All New Salsa recipes (2016) call for fresh lime juice. Healthy Canning confirmed in several telephone calls July 2016 to Ball that in their salsa recipes appearing in their 2016 All New Book of Canning calling for fresh lime juice, you can use either Key Limes (aka Mexican Limes) or the larger Persian Limes (aka Bearss, aka California) limes. So for those recipes, the tested lab results from Ball’s test kitchens overrule the Key Lime advice above from Pacific Northwest — for those particular lab-tested recipes only.
In a Zoom meeting with Ball staff in July 2022, Ball confirmed that those recipes calling for fresh lime juice were absolutely lab-tested for safety. However, they have been transitioning to calling for bottled instead because of a consumer perception that bottled was safer in those recipes.
Bottled lemon juice and sulfites
Some people are concerned about sulfites in the bottled lemon juice.
The University of Minnesota Extension has this advice:
Bottled lemon and lime juice contain sulfites. If you or family members have a sulfite sensitivity or allergy, use citric acid or vinegar or substitute frozen lemon juice (not lemonade) that you find in the grocery store frozen section – use same amounts as bottled lemon juice.” [12] University of Minnesota Extension. Home Food Preservation Newsletter. August 2012. Accessed March 2015 at https://www.extension.umn.edu/food/food-safety/home-food-preservation-newsletter/docs/home-preservation-august-2012.pdf.
Or, again, you can also swap in citric acid in appropriate ratios.
History of the recommendation for bottled citrus juice
The recommendation for bottled lemon juice goes back to at least the 1980s. In June 1986, an extension agent from Maryland wrote:
Bottled, not fresh lemon juice should be used because the acid content of bottle lemon juice is standardized.” [13]Jenkins, Kathryn. New guidebook available this fall giving up-to-date home canning tips. Frederick, Maryland: The Frederick News-Post. 19 June 1986. Page F-1.
The recommendation applied equally to lime juice.
In 2016, Ball created some controversy in the canning world with its All New canning book, when it called for fresh as opposed to bottled lime juice for its new salsa recipes in that book.
References
Luke
New to canning, and sensitive to sulfites. I’ve only pressure-canned low-acid food so far, but clearly a lot of things can only be done through water-canning so I’m hoping to start doing so (well, actually steam-canning because it looks quicker and easier).
I get terrible heartburn from some commercially canned foods. Including those that use: commercially produced ‘lemon juice’ (sulfites as preservatives) or citric acid (sulfites from processing maize). Unfortunately, home canning already high-acid foods, ironically enough, generally requires the use of one of those two acidic ingredients because no testing has been done as to the safety of pressure canning beyond replicating the water-canning process.
(Vinegar, although referred to in general terms as contributing to acidification, doesn’t appear to be presented as a specified alternative to citric acid or lemon juice in any recipes. Even if it did, just about all vinegars are sulfite-rich. Sulfites in wine for balsamics, white wine vinegars. Sulfites in malt processing for malt vinegar. The one exception is the difficult-to-find real rice wine vinegar: 99% are ‘rice-wine flavoured’. But that, if it does specify its acidity, will do so in Japanese, which I will not understand.)
It’s possible a properly purified citric acid would sufficiently reduce the sulfites so they don’t bother me. But in Australia, claims of ‘pharmaceutical grade’, ‘USP’ etc. in citric acid sold directly to the public appear to be largely a matter of sellers writing it on labels attached to repackaged food-grade products.
I was very tempted to start water-canning with fresh lemon juice. And after looking into it, I’m not sure there realistically much more of a risk than commercially bottled lemon juice. But I unfortunately mean that in a bad way, in that the commercially packaged lemon juices appear not much less risky.
An extensive study of Spanish lemons (https://www.sciencedirect.com/science/article/abs/pii/S0308814614005998) saw ‘lemon juices, calculated as anhydrous citric acid (ACA) pH 8.1, varied from 35.1 to 65.6 g/L in direct juices and from 38.4 to 78.1 g/L in reconstitutes.’ The authors noted that the ‘values are similar than other values obtained by different authors for Spanish and Chinese lemons (García-Sánchez et al., 2003, Pérez-Pérez et al., 2005, AIJN, 2013).’
(Ie. at least some commercially packaged lemon juice–at 3.84%–fell below the ‘4.5%’ w/v figure apparently inscribed in U.S. law.)
Indeed, the ‘4.5% acidity law’ does not necessarily change the real position in the U.S., either. I’m looking at the (very less extensive) empirical testing in https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2637791/ and seeing that:
a. neither of the commercially prepared lemon juices (‘Realemon’ and ‘Concord foods’) met the standard of ‘a titratable acidity content of not less than 4.5 percent, by weight, calculated as anhydrous citrus acid’; and
b. The natural lemon juices had more citric acid w/v than commercially prepared lemon juices.
It doesn’t seem like getting bottled lemon juice is much more of a real-world guarantee of pH to me. And the ‘4.5%’ law won’t have any application to me in Australia anyway.
Having looked at all that, I must admit I’m somewhat less interested in using fresh lemon juice. In fact, I’m not sure I’d want to be using commercially bottled lemon juice whether or not it had sulfites.
Citric acid is plainly more consistent in its acidity (and therefore safer) than either category of lemon juice.
I’ve considered doing pH testing. But I’ve got to say that looking into the calibration procedures required every single canning session for pH meters that require frequent probe replacement or entire meter replacement does not make canning look very fun, inexpensive, or even much more convenient or easier than titrating out the solution to determine the pH using ‘old-fashioned’ methods.
But more fundamentally, you can’t test for something if you don’t know what you’re looking for. So far as I can tell, the USDA has not said what assumptions it actually makes about the minimum ‘bottled lemon juice’ pH. It’s perfectly possible the commercially bottled stuff falls below it occasionally or regularly.
Maybe the safe minimum is 4.5%, in which case the studies above suggest people are being regularly put at risk. Maybe it’s 4%, in which case you may not be able to can things on a semi-regular basis and end up with a mountain of unused food. I’m not sure you can safely assume anything about the safe minimum level.
It appears the safest and probably easiest option is to somehow procure a highly purified citric acid and see if it still gives me heartburn. Does anyone know how to get some in Australia (or that can be shipped to Australia) that is also food-safe? I’m not too excited about the phrase ‘Keep away from foodstuffs, beverages and feed’ in the MSDS of this one for example: https://www.itwreagents.com/united-states/en/product/citric+acid+anhydrous+%28usp%2C+bp%2C+ph.+eur.%2C+jp%29+pure%2C+pharma+grade/141808
Another alternative is citric acid derived from citrus, etc. rather than from corn that has no sulfites added as preservative. I’m not sure if this legitimately exists as a product any more though given the cost of production.
(The undeclared sulfites in maize-derived citric acid are produced when maize gets steeped in sulfuric acid as the first processing step before it becomes ‘food starch’, ‘glucose’, ‘maltodextrin’, ‘citric acid’, ‘molasses’, ‘malt’ and just about every other possible thing that can be made from it thanks to a marriage of industrial food science and longstanding farm subsidies paid by the US government to corn farmers as a result of something that must have happened historically but is completely inexplicable to persons living outside the U.S.)
Alexander Nied
Would it be acceptable to blend fresh lemon juice and then test it with a high-resolution digital PH meter to verify if it is equal or greater to the acidity of bottled lemon juice and, if so, to then use it in a canning recipe in place of bottled lemon juice?
And, as a follow-up, if the above method were acceptable, would it make sense to use something like citric acid to increase the acidity of lemon juice that measured below that of bottled lemon juice in order to bring it to an acceptable acidity level for canning purposes?
Lance Moreau
I have a recipe that called for the juice of 1/2 a lemon. I doubled my recipe and used 1 whole lemon. Its a trusted recipe but my 1st time doing. Was this enough? And will it hold stable in the pantry? Its a blueberry bourbon jalapeño jelly recipe but acts and looks more like a jam. If you search this recipe name you will find it on Google. Thank you bunches 🙂🙂🙂
Healthy Canning
A trusted recipe is one that was developed by a reputable source AND was lab-tested for source. I’m not finding any indication of which reputable home canning source, with trained home canning professionals, developed that recipe?
JR
So with the strawberry lemonade concentrate recipe (it’s either the Ball book or the other one), it calls for lemons. It’s going to taste good using the lemon juice in the bottle? It doesn’t say you can use it-I believe it mentioned fresh lemons. I would hate to make and give as a gift and have it suck. Lemons are so expensive. Someone said they used close to 20 lemons.
Stephanie
May I substitute fresh lime juice where fresh lemon juice is called for?
Healthy Canning
As lime juice is more acidic than lemon juice even, yes, you may.
Kritz
Hi! 🙂 Can you please recommend a good brand of bottled lemon juice or an example? Is it 100% pure lemon juice?
I’m from the Philippines and our local products can be different from products from the U.S.
But we do have imported U.S. products available here. It can just either be a bit difficult to find or a bit pricey.
TIA. 🙂
Healthy Canning
Hi Kritz, I see that there are several Filipino brands of bottled liquid lemon products which are labelled lemon-flavoured “drink” or “lemon water.” As you know, that’s not 100% pure, which is why you’re asking of course…. I’ve been Googling and trying to find 100% pure bottled lemon juice for you in the Philippines but haven’t had any luck — I agree imported products can get ridiculously pricey!
Tara Brady
If a recipe calls for 1 1/4 cup of cider vinegar how much lemon juice to substitute it with?
Healthy Canning
What is the recipe you are working with Tara?
Melissa
Hello,
What is the ratio of lemon juice to add to non-citrus jam to ensure the max pH? I also use homemade Apple pectin from Granny Smith apples, would this affect that ratio? Also, can you recommend a good pH meter for canning?
Thanks!
Healthy Canning
Hi Melissa,
Check out this page, where I cover pH meters:
Re the jam acidity and pectin questions, I’m going to suggest that you pose those questions to someone like the people at Pomona Pectin. https://www.pomonapectin.com/ They have tons of experience in developing safe jam recipes.
Hope that helps!
Rob
Randal,
Can I use Ball Fruit-Fresh in place of vinegar or lemon juice? If so, how do I determine how much to use? The label says to add 1 tsp to each cup of liquid in the recipe. Does that mean to add 2 tsp for pint jars, 4tsp for quarts, etc.? Would it be added to each jar as they are being filled or stirred into the entire hot recipe?
I guess my real question is: Does the Fruit-Fresh impart a flavor? For instance, I don’t care for the vinegar flavor that comes through in home-canned salsa.
Thanks
Healthy Canning
Hey Rob,
Sadly, you can’t use Ball Fruit Fresh (aka ascorbic acid aka vitamin C) for that purpose. It’s slightly acidic, but only just enough to prevent browning. It’s not acidic enough beyond that to provide safety. https://www.healthycanning.com/home-canning-theory/acidifying-tomatoes-for-safe-home-canning/#don8217t-use-ascorbic-acid . And, what’s more, Vitamin C is volatile and is destroyed by heat, so it won’t even survive in the jars to keep them safe.
Instead of vinegar, you could try lime juice to compliment the salsa taste. Or, citric acid, which has the least discernible citric taste of all, in many people’s opinion: https://www.healthycanning.com/citric-acid-and-home-canning/
If it’s specifically salsas you are thinking of, here’s a page of collected info / resources about salsa: https://www.healthycanning.com/salsas/
Cheers.
Nikki
i would like to dry lemons and grind them into a powder and use this in place of citric acid in all recipes for canning. Do you know of a conversion chart for this?
Healthy Canning
Sorry, nope, haven’t seen any such chart. You’d need to contact Ball or the NCHFP to ask them, to make sure you have safe conversion rates for homemade versus commercial which would have certified acidic ratios (presumably.) Or, try Linda Ziedrich over at https://agardenerstable.com/ : you may find her more willing to at least intellectually entertain such a question. Good luck!
Nikki
Thanks Randal. I will check into all 3.