Safe Substitutions in Canning: What You Can and Can't Change

If you’re new to water bath canning (or even if you’re a pro!), you’ve likely come across a tested recipe and thought– can I change this?

Can I use apple cider vinegar instead of white? Or can I reduce the sugar? Can I add in more garlic?

Some of these changes are completely fine, and some of them can make your jar unsafe. These are the rules on what’s safe to change in canning, and what you cannot adjust.

Table of contents

One Rule that Helps Explain the Others

The safety of home-canned food depends on two things: the pH, or the acidity and heat. So when you ask yourself if you can change something in a tested recipe, you’re really asking about those two things.

To safely store at room temperature for months, the contents inside your jar need to be at a pH of 4.6 of lower because this acid level prevents Clostridium botulinum spores from germinating. All recipes that have a pH of 4.6 of lower can be processed using a water bath canning method– which is just boiling the jars at 212 degrees F.

Contents that have a higher pH must be processed using a pressure canner because they need more heat that boiling water cannot reach– between 240 and 250 degrees F.

If you are changing a recipe to increase the pH above 4.6, then you’ve made a low-acid food that cannot be processed using a water bath canner.

The heat of the boiling water bath or pressure canner is needed to help kill the spores and penetrate the jars, which is also why you can never increase the canning jar size.

Several things factor into whether heat can pentrate the coldest point in the jar:

Density: Sugar, salt and starch can change the thickness, or viscosity, of the mixture which alters heat penetration. Penn State gives the example of starchy lima beans taking longer to process than more pourous green beans.
Size, Shape and Temperature of Food: A whole cucumber will take longer than a cucumber slice.
Size and Shape: Both will affect how quickly the heat moves in the jar.

A Glass Mason Jar Filled With Cucumber Slices, Fresh Dill, Mustard Seeds, Black Peppercorns, And Other Pickling Spices—Perfect For Making Refrigerator Pickles. Another Jar Is Partially Visible In The Background.

Changes that are Safe

Dried Herbs and Spices

Generally, adding dried herbs and spices can be changed. This means you can swap the pickling spice blend, double the mustard seed, leave out the celery seed, add turmeric, ect.

The one place where there is more of an exception is homemade canning salsa. Because salsa sits right at the edge of the acid margin, you want to be careful with how much dried herbs you add. A teaspoon or so is usually OK, but don’t add fresh herbs as those are usually low-acid and may change the pH of the recipe.

Salt (except in fermenting)

Salt is usually added for flavor in vegetables, salsa, meats, soups, ect and omitting it is not a safety issue. For example, in my canning salsa, the salt is there for flavor and not preservation, so it’s OK to reduce (or even increase) depending on taste preference.

However, you can never reduce the salt in fermented products. The correct salt concentration is essential in sauerkraut and crock dill pickles, where salt favors the growth of desirable bacteria and inhibiting others. If you want to reduce the salt in pickles, then you can use a tested reduced-sodium pickle recipe.

If you are worried about sodium, then the better option is to rinse fermented products before serving. For example, rinsing sauerkraut before serving reduces the sodium by 30-40%.

Vinegar Type

As long as the vinegars contain the same % of acidity, you can interchange them. For example, cider vinegar is 5% acetic acid and distilled white vinegar is also % acetic acid so those can be used interchangably for safety, but note that cider vinegar has a darker color and will change the appearance of a recipe, while white vinegat won’t.

You must use a vinegar that has 5% acidity and many other vinegars, like balsamic or rice wine, don’t.

Smaller Jars

You can use a smaller jar size, but you cannot use a large size than what the recipe calls for. This is because of the heat penetration and the amount of acid in each jar– it’s calculated to the size of the jar and adjusting upwards isn’t allowed.

Produce within the same type

Peppers: You can substitute sweet peppers for hot and vice versa, measure for measure. Penn State adds that bell, long green, and jalapeño peppers can be substituted for each other as long as the total amount isn’t increased.
Onions: red, white, and yellow are also interchangeable, measure for measure.
Tomatoes: You can use any variety or color.
Tomatillos: These can replace tomatoes as long as the total amount stays the same.
Zucchini or summer squash: Try zucchini in a pickle recipe! You can replace cucumber in any approved relish recipe.
Peaches and nectarines: are interchangeable in jam, as are apples and pears. The only exception to this is white peaches as some varieties are lower acid.
Cucumbers: English or grocery-store cucumbers can replace pickling cucumbers, though the quality may be inferior.

Reducing low-acid vegetables

It’s always safe to reduce low-acid vegetables, like onion, celery or green peppers but you cannot increase them. I don’t recommend decreasing low-acid vegetables like tomatoes in a salsa recipe.

A Mason Jar Filled With Layers Of Chopped Yellow Peppers, Lemons, Herbs, And Spices, Set Against A Neutral Background. Ideal For Canning Banana Peppers.

Changes that Are Not Safe

Adding low-acid vegetables

You cannot increase the total amount of low-acid vegetables in a recipe. Adding extra onion, peppers, or other vegetables to salsa or other water bath canning recipes will change the acidity and make them unsafe.

Reducing the acid

You also cannot reduce the amount of acid in a tested recipe. Reducing the vinegar in salsa or a pickled product can make the recipe too low-acid and again, not safe.

If you are trying a recipe and the results taste too tart for you, then the fix is to add a little more sugar, but not to cut the vinegar.

However, you can swap vinegar for bottled lemon juice in salsa recipes that call for vinegar. Lemon and lime juice are more acidic than 5% vinegar, so swapping to bottled citrus for vinegar will keep you safe. The FDA puts vinegar pH at 2.40-3.40 and lemon juice at 2.0-2.60. That is why it’s OK to use just lemon or lime juice, but not vinegar, in recipes that call for lemon or lime juice.

Thickening Anything

Don’t thicken salsa before canning, or thicken tomato products, vegetables or soups with flour or cornstarch.

Adding starch or thickeners changes how fast heat penetrates the jars and can result in undercooking. If you want a thicker product, you can strain it after canning.

Adding untested ingredients

You cannot add corn or black beans to any salsa recipe, or substitute corn or black beans for peppers or onions. You also cannot add meat to a recipe unless the recipe has been tested with it. You also cannot add fat to canned meat products.

Fresh Herbs

Penn State’s guidance is that you can change the type and amount of dried herbs and spices, but not fresh herbs. Fresh herbs are a low-acid plan, and the tested allowance is specific. Adding fresh herbs that the recipe doesn’t call for can change the final pH.

If you want fresh herb flavor, then adjust it when you open the jar! Plus, fresh herbs change color when canned, so it’s better to add finely chopped herbs when you open a jar than before canning.

Changing Headspace

The headspace suggestion is dependent on the recipe and can’t be changed. Too little headspace can cause food to bubble out during processing and prevent a seal. Too much headspace and the top of the food is likely to discolor, and the jar may not seal because there isn’t enough processing time to remove all the air.

Changes to the heating setup also matter, like not fully submerging the jars or putting a towel in the bottom of a water bath canner (why do people recommend this!?), because they affect heat distribution and penetration.

A Glass Jar Filled With Vibrant Low Sugar Peach Jam, Sealed With A Silver Metal Lid, Sits In Front Of Two Similar Jars On A Light Surface.

Sugar: it depends!

Sugar is a little tricky when it comes to canning safety, because the rules change based on what you are making.

In canned fruit

If you are canning fruit, like whole peaches or pears, then sugar is there to help preserve color and texture and add flavor. You can safely reduce or eliminate it depending on preference. Or, you can replace up to half of the sugar with honey, or replace a sugar syrup with a light fruit juice, like white grape or apple juice.

The big trade-off, of course, is quality because fruit that is canned in water isn’t going to taste as good as fruit canned in sugar. The fruit will also spoil faster once opened because sugar also acts as a preservative once your jar is opened.

In pickles and salsa

You can reduce sugar in any tested quick-process pickle or salsa recipe.

In jam and jelly

Traditional jam and jelly recipes call for lots of sugar —about 65% of the final product by weight — to thicken and gel the jam. Sugar also acts as a preservative by binding water, which prevents bacterial growth.

Reducing sugar in a traditional jam or jelly recipe will result in a runny and potentially unsafe product.

If you want to make a low-sugar jam or jelly, you’ll need a recipe tested with low-sugar pectin. Low-methoxyl pectin is derived from citrus and forms a gel by binding with calcium rather than using sugar and acid. Products made with it are specifically tested with this pectin and can’t be interchanged with traditional jam recipes.

I’ve got three: low-sugar peach jam, low-sugar blackberry jam, and low-sugar strawberry jam.

The one exception is canned hot pepper jelly: peppers are lower-acid than fruit and rely on acid for safety, so it’s best not to change the sugar in this recipe, since it’s tested and verified. I’ve also got a canned pepper confetti jelly recipe that’s fantastic with crackers!

What about honey?

If you want to use honey, you can replace up to 1 cup of sugar with 1 cup of honey for every 6-pint recipe that uses pectin. In recipes with no added pectin, you can use honey in up to half of the sugar, and decrease the liquid by the amount of honey added.

Sugar Substitutes

Sucralose, stevia or other sugar substitutes don’t have the same preservative properties of sugar and may change the flavor. If you want to use these, the guidance is to add them after the jars are opened.

There are a few exceptions to this; NCHFP has developed three recipes using Splenda: a quick pickled sweet cucumber, pickled beets, and pickled cantaloupe.

Why you need bottled lemon juice

You need to use bottled lemon juice, not fresh lemon juice, because bottled lemon juice is a measured quantity of acid, and fresh lemon juice isn’t.

Bottled lemon juice is standardized under FDA regulation; lemon juice that’s prepared from concentrate must have an acidity of not less than 4.5% by weight. That is the safety measure that canning recipes are built around, which is why fresh lemon juice isn’t the same.

If your finished product tastes too tart, you can add a small amount of sugar to balance it. This is why I use citric acid when I can whole tomatoes, as it doesn’t alter the flavor at all.

Firming Agents

You can add calcium chloride, sold as Pickle Crisp, to add crispness to pickles. Don’t use pickling lime unless the tested recipe calls for it.

Other firming agents like alum and food-grade lime can be used only in recipes tested with them.

A Glass Jar Filled With Sliced Cucumbers, Herbs, And Spices Submerged In Liquid, Likely Homemade Refrigerator Pickles, Sits On A Gray Surface With Another Jar Blurred In The Background.

Quick Reference Table

Change	Safe?	Notes
Change types/amounts of dried spices and herbs	Yes
Reduce or omit salt	Yes, except for fermented	Not in sauerkraut or crock dill pickles
Swapping cider vinegar for white vinegar	Yes	OK because they are both 5%. Other vinegars only if the recipe allows
Using a smaller jar	Yes
Using a larger jar	No
Swap pepper or onion varieties; measure for measure	Yes	Total amount can’t increase
Reduce low-acid vegetables	Yes
Reduce vinegar or lemon juice	No	Add sugar if it’s too tart
Replacing vinegar with bottled lemon juice	Yes	Only this direction; can’t replace bottled lemon juice with vinegar
Adding extra onion, peppers or other low-acid vegetables	No	Dilutes acidity
Adding thickeners	No	Changes heat penetration
Add fresh herbs that aren’t called for	No	Dried herbs are safer
Reduce sugar in canned fruit	Yes	Quality will change, but not safety
Reducing sugar in traditional jam	No	Use a tested low- or no-sugar pectin recipe instead
Changing headspace	No	Can affect the seal
Doubling a jam recipe	No	Heating times and temperature changes