Alum substitutes
Alum substitutes — 6 options, ranked, with the exact amount
Also called alum powder, pickling alum, potassium alum, potassium aluminum sulfate
Use Calcium chloride (pickle crisp)
1/8 tsp for every pint jar
Leave the alum out; a tested pickle recipe made with fresh cucumbers does not need it. For extra crunch, add calcium chloride granules (sold as Pickle Crisp) to each jar: 1/8 teaspoon per pint or ¼ teaspoon per quart. It firms the pickles without changing the acidity or the taste. Soaking the cucumbers in ice water for 4 to 5 hours and cutting 1/16 inch off the blossom end do most of the rest. Do not change the vinegar, water or salt amounts in a tested recipe.
- Verdict —
- Works
- The tweak —
- Add 1/8 teaspoon to each pint jar or ¼ teaspoon to each quart jar, on top of the packed vegetables, before pouring in the brine. Do not use more than the package says.
- Best for —
- quick vinegar pickles
Updated 8 Oct 2026 · no sponsored swaps
But first: what’s the alum doing?
Pick your caseWhat kind of pickle is the alum in?
Leave the alum out; it does not firm this kind of pickle. Add 1/8 teaspoon calcium chloride per pint if you want more crunch, soak the cucumbers in ice water first, and trim the blossom ends. Keep the tested recipe's vinegar, water and salt exactly as written.
Notes on calcium chloride (pickle crisp), ice water soak or trimmed blossom ends
1/8 tsp per pint jar
Alum is not needed here either. Trim the blossom ends, keep the cucumbers fully under the brine, and add a grape leaf if you want extra firmness.
Notes on trimmed blossom ends or grape leaves
Replace the alum soak with 4 to 5 hours in ice water. If the recipe will be canned for the shelf, check its vinegar-to-water proportions and processing time against a current tested recipe before you make it.
Notes on ice water soak or calcium chloride (pickle crisp)
Use a play dough recipe written for cream of tartar; the common version uses 2 teaspoons per cup of flour. Nothing else on this page applies to play dough.
In old pickle recipes alum was a firming agent: a pinch in the jar or a soak in alum water was meant to keep cucumbers crisp. Current guidance from the National Center for Home Food Preservation is that alum may firm fermented pickles a little, does not improve quick-process vinegar pickles, and is unnecessary either way. Crispness comes mostly from fresh pickling cucumbers, trimmed blossom ends, cold soaking and correct processing, with calcium chloride as the optional helper.
Every option, one card
Ranked| # | Substitute | Instead of alum | Verdict |
|---|---|---|---|
| 1 | Calcium chloride (pickle crisp)quick vinegar pickles | 1/8 tsp per pint jarWorks | Works |
| 2 | Ice water soakany cucumber pickle | See notesWorks | Works |
| 3 | Trimmed blossom endsevery cucumber pickle, quick or fermented | See notesWorks | Works |
| 4 | Grape leavesfermented crock pickles | 1 leaf per quart jarTweak it | Tweak it |
| 5 | Pickling limeold-fashioned lime pickles made from a tested recipe | See notesYou'll taste it | You'll taste it |
| 6 | Low-temperature pasteurizationcucumber pickles whose tested recipe allows it | See notesTweak it | Tweak it |
| Not a swap | Cream of tartar | not a swapNot for this | Not for this |
| Not a swap | Baking soda | not a swapNot for this | Not for this |
Calcium chloride (pickle crisp)
none at the label amount
Food-grade calcium chloride granules, sold with canning supplies, firm the pectin in the cucumber and are the modern replacement for alum and for lime soaks.
- Best for
- quick vinegar pickles, pickled peppers and green beans
- Texture
- firmer, crisp
- Prep
- Add 1/8 teaspoon to each pint jar or ¼ teaspoon to each quart jar, on top of the packed vegetables, before pouring in the brine. Do not use more than the package says.
- Suits
- vegan, gluten-free
It goes into the jar and stays there, so there is no soaking or rinsing step. It does not lower the acidity of the brine. Too much gives a bitter, salty taste. It helps keep a fresh cucumber firm; it cannot firm up one that was already soft.
Ice water soak
no change
Soaking whole cucumbers in ice water before pickling firms them with nothing added.
- Best for
- any cucumber pickle, old recipes that soak in alum water
- Texture
- crisper
- Prep
- Cover the cucumbers with ice and water and hold them in the refrigerator for 4 to 5 hours before pickling, adding ice as it melts.
- Pantry
- Likely in your cupboard
- Suits
- vegan, gluten-free
This replaces an alum-water soak step directly. It works best on cucumbers picked within 24 hours; it will not rescue ones that have gone rubbery.
Trimmed blossom ends
no change
The blossom end of a cucumber carries enzymes that soften pickles, and slicing it off removes them.
- Best for
- every cucumber pickle, quick or fermented
- Texture
- keeps pickles from softening
- Prep
- Cut 1/16 inch off the blossom end of each cucumber, the end opposite the stem, and discard it.
- Pantry
- Likely in your cupboard
- Suits
- vegan, gluten-free
This is a step, not an ingredient, and it does more for texture than alum does. Pair it with pickling cucumbers, not waxed slicing cucumbers, which stay soft whatever you add.
Grape leaves
faint tannic note
A traditional addition to crock pickles: the tannins in the leaf slow the enzymes that soften cucumbers.
- Best for
- fermented crock pickles, refrigerator pickles
- Texture
- slightly firmer
- Prep
- Rinse 1 fresh, unsprayed leaf and lay it in the bottom or on top of each quart jar or over the crock. Start with one; more can add bitterness.
- Pantry
- Special trip
- Suits
- vegan, gluten-free
The leaf works against the same enzymes that trimming the blossom end removes, so it adds little if you have trimmed the ends. Jarred grape leaves packed in brine are salty and softer; rinse them well. Do not add a large quantity of leaves to a canned recipe that does not call for them.
Pickling lime
none if fully rinsed
Food-grade calcium hydroxide used as a soak before pickling. It firms cucumbers well, and it has to be rinsed out completely.
- Best for
- old-fashioned lime pickles made from a tested recipe
- Texture
- very firm
- Prep
- Soak the cucumbers in the lime-water solution for 12 to 24 hours as the tested recipe directs, then drain, rinse, and soak in fresh water for 1 hour. Repeat the rinse and the 1-hour soak two more times.
- Pantry
- Special trip
- Suits
- vegan, gluten-free
Lime is alkaline. Any left in the cucumbers lowers the acidity of the brine, and acidity is what makes a canned pickle safe. Never skip or shorten the three rinses, never add lime to the jar, and use only food-grade pickling lime, not garden or builder's lime. Calcium chloride gives a similar result without this risk.
Low-temperature pasteurization
no change
A gentler processing method that keeps pickles firmer than a boiling water bath.
- Best for
- cucumber pickles whose tested recipe allows it
- Texture
- firmer than boiled jars
- Prep
- Hold the filled jars in water at 180 to 185°F for 30 minutes, checking with a thermometer the whole time so the water never drops below 180°F.
- Pantry
- Likely in your cupboard
- Suits
- vegan, gluten-free
Use it only when the tested recipe says low-temperature pasteurization is an option. It is not safe as a general replacement for the boiling water process in other recipes.
Cream of tartar
slightly sour
Another white powder from the spice aisle, often confused with alum.
- Best for
- homemade play dough, not pickles
- Texture
- no firming
- Pantry
- Likely in your cupboard
Cream of tartar is a mild acid and does nothing to firm a pickle. The confusion comes from homemade play dough, where either one is used: there, a recipe written for cream of tartar (commonly 2 teaspoons per cup of flour) replaces a recipe written for alum.
Baking soda
soapy, flat
An alkali, the opposite of what a pickle jar needs.
- Best for
- nothing in pickling
- Texture
- softer
- Pantry
- Likely in your cupboard
Baking soda neutralizes vinegar. Adding it to pickles lowers their acidity, which is the safety control in home canning, and it softens vegetables.
Don’t swap it here
3 cases- SafetyA tested canning recipe, when the swap would change the vinegar, water, salt or vegetable amounts.Leave the alum out and change nothing else. Calcium chloride at the package amount can be added without affecting acidity.
- SafetyPickling lime that has not been rinsed out, or lime added straight to the jar.Rinse and resoak in fresh water for 1 hour, three times, or use calcium chloride, which needs no rinsing.
- Soft, old or waxed slicing cucumbers.Use unwaxed pickling cucumbers within 24 hours of picking, or make relish.
Questions
6 questionsWhat can I use as a substitute for alum in pickles?
Nothing is required. Tested recipes made with fresh pickling cucumbers are crisp without alum. If you want a firming agent, use calcium chloride (Pickle Crisp) at 1/8 teaspoon per pint or ¼ teaspoon per quart, added to the jar. An ice water soak and trimmed blossom ends help as much.
Can I leave alum out of a pickle recipe?
Yes. Alum has no role in the safety of a pickle, and current home-canning guidance says it is unnecessary and does not improve quick-process pickles. Leave it out and keep the vinegar, water and salt as the recipe states.
Is alum the same as cream of tartar?
No. Alum is potassium aluminum sulfate and cream of tartar is potassium bitartrate, a mild acid from winemaking. They are both white powders in the spice aisle, and both are used in homemade play dough, but cream of tartar will not firm pickles.
Is Pickle Crisp the same as alum?
No. Pickle Crisp is calcium chloride. It firms pickles through calcium, the way a lime soak does, and it goes straight into the jar with no rinsing. It is the firming agent current canning guides suggest when you want one.
Can I use pickling lime instead of alum?
Only with a tested lime-pickle recipe and only as a soak that is fully rinsed out: drain, rinse, and resoak in fresh water for 1 hour, three times. Lime left in the cucumbers lowers the brine's acidity and can make the pickles unsafe. Calcium chloride is the simpler choice.
What can I substitute for alum powder in play dough?
Use a recipe written for cream of tartar, which is the more common version: typically 1 cup flour, ½ cup salt, 2 teaspoons cream of tartar, 1 cup water and 1 tablespoon oil, cooked until it forms a ball.
Tips for substituting alum
5 tips- Pickle within 24 hours of picking, and keep the cucumbers refrigerated until then. Freshness does more for crunch than any additive.
- Cut 1/16 inch from the blossom end of every cucumber. If you cannot tell which end it is, trim both.
- Measure calcium chloride with a measuring spoon: 1/8 teaspoon per pint, ¼ teaspoon per quart. More makes the pickles taste bitter.
- Soak whole cucumbers in ice water for 4 to 5 hours in the refrigerator before packing the jars.
- Process for exactly the time the tested recipe gives for your altitude. Extra minutes in boiling water soften pickles.