In a prior series of posts, I set the stage for trying to produce a decent-tasting canned sour pickle, sodium-free. I established that:
- Salt is not necessary for safely canning pickles as long as at least half the liquid is standard (5%) vinegar (or, better, at least one-quarter of the contents of each jar is standard (5%) vinegar).
- That said, you must can them in boiling water. You cannot safely use the pasteurization technique (30 minutes at 180F) for canning no-salt pickles, even though pasteurization results in a crisper pickle.
- I canned pints of pickles, starting with reasonably fresh cucumbers.
- The resulting no-salt pickles were firm but not crisp. Not mushy, but not crunchy either.
- Neither pickle crisp (calcium chloride) nor the ice-bath technique seemed to make any noticeable difference in pickle crispness.
- Taking out all the salt, and putting salt substitute (potassium chloride, KCl) into the recipe, at half the rate at which you would you would use salt, gave the pickle a slightly salty flavor with no off (“metallic”) taste from the salt substitute.
- None of the salt-free pickles tasted like a real, high-salt pickle.
I’m now eating the jar of my best no-salt pickle (batch 2, with salt substitute) and trying to figure out where to go from here. I note that:
- Spears are more pleasant to eat than the whole pickles, owing to the lack of total crispness. The toughness of the peel of the cucumber is less of an issue.
- There’s a slightly sweet note that I don’t like in a pickle.
- The salt flavor is subdued, compared to a normal pickle.
- They are bland. The overwhelming flavor note is white vinegar.
Accordingly, the plan for fine-tuning the recipe for a no-sodium pickle is as follows:
Base recipe:
- Make pickle spears, not whole pickles.
- Reduce the sugar in half.
- Add a second sour note using citric acid.
- Raise the salt substitute to 3/4ths of (what would have been) the salt.
- Use more dill, and add garlic and onion in the base recipe.
Variations:
- Use salt substitute (KCl) 1:1 with original salt volume.
- Can some with hot (e.g. cayenne) peppers in the jar
Lemon juice/vinegar equivalency?
Of those, the only thing that requires any figuring is the amount of citric acid to use. And, separately, whether I can reduce the vinegar due to the presence of citric acid.
Per the USDA Guide, for home-canning of tomatoes, for pints, you may guarantee acidity below the 4.6 cutoff for safe canning with:
- One tablespoon (one-half ounce) bottled lemon juice OR
- One-quarter teaspoon citric acid OR
- Two tablespoons (one ounce) 5% vinegar.
Based on that, it looks like you can use either bottled lemon juice or standardized vinegar to acidity a brine, at a ratio of 1:2. That is, one tablespoon of lemon juice substitutes for two tablespoons of vinegar.
(Separately, I note that the recommended amount of vinegar for safe canning of tomatoes is one-quarter of the amount required for safe canning of cucumber pickles. (A pint jar should have at least four ounces of standard vinegar for canning pickles.) That has to be a consequence of the acidity of the underlying vegetable. For the most part, tomatoes will typically be under pH 4.6 naturally. There, the added acid is just insurance for the occasional variety or batch that is not. Cucumbers, by contrast, have a mean pH of about 5.6.)
That makes it look as if adding quarter-teaspoon of citric acid to each pint should, in theory, let me reduce the vinegar by 25% (from four ounces per final pint jar, to three).
In theory.
But I also see a warning on a reputable website that you cannot substitute citric acid for vinegar in salsa recipes, owing to the fact that peppers and onions are low-acid foods. (Comments, in this article.) That said, the referenced booklet of salsa recipes certainly seems to exchange one-half cup bottled lemon juice for what would have been one cup of standard (5%) vinegar in its salsa recipes (this reference). Exactly as you would expect, based on the bullet points just above.
However, the only cucumber pickle recipes I can find with citric acid more-or-less use it as a flavoring, not as an acidifying agent. And it’s rare even to see that. So I cannot find somebody of standing directly stating that it’s safe to substitute lemon juice (citric acid solution) and vinegar (acetic acid solution) in this ratio.
I would say that, to a close approximation, nobody had addressed this critical question of substituting citric acid for acetic acid in a canned pickle recipe. But it clearly must be feasible, as there are salsas containing low-acid food such as onion, pickled entirely with lemon juice, per the reference above. Onions come in at a pH of just about 5.5, same as cucumbers (reference).
You can find a ton of recipes for various foods picked in lemon juice — cucumber, onions, and so on. The problem is, these all appear to be refrigerator-pickle recipes, not recipes for shelf-stable canned pickles.
Here’s one exception, but not from a known trusted source. That one uses a 50/50 water lemon-juice brine. Ditto with this one.
Bernadin of Canada (same company as Ball, U.S.) has a recipe for pickles canned with lemon juice. To me, that’s as reliable a source as getting it out of the Ball Blue Book. But that’s an extremely acidic recipe. There is no water dilution. The pickling brine consists of two-thirds vinegar, one-third lemon juice. So, while that is a pickle recipe, and does have some lemon juice in it, the overall acidity of the picking brine is far higher than that of a standard pickle (where the brining liquid is half vinegar, half water). Based on the chemistry of the recipe, it’s not clear that they are counting on the acidity of the lemon juice at all.
Here’s where I finally come out on this.
I bet that you can, in fact, freely substitute bottled lemon juice and standard (5%) vinegar in a 1:2 ratio in any canning recipe.
But I’m not quite ready to bet my life on it.
For this round, I’m going the “acetic acid is a flavoring” route. I’ll keep the existing vinegar brine strength (half vinegar, half water), and add the equivalent of a quarter-teaspoon of citric acid per finished pint of pickles.
Next steps and the long wait.
I’m now going to put up a few more pint jars following those directions.
Unfortunately, because this is all about the flavors, it’ll be another couple of weeks before I have results. I’ll report back when I open these up around the end of July.
