Canning vegetable broth is a straightforward pressure-canning project: strain a thin, unthickened broth, hot-pack it into jars with 1 inch of headspace, and process pints for 30 minutes and quarts for 35 minutes in a pressure canner, adjusting pressure for altitude. That is the tested method published by Ball and Bernardin for vegetable stock.
A water bath canner is not a workaround. Vegetable broth is a low-acid food. Boiling water never reaches the temperature needed to destroy Clostridium botulinum spores, and extra time, extra vinegar, or extra tomatoes does not change that.
If you already make scrap broth and freeze it, canning is how you get the same product onto a pantry shelf. The work is in the simmering and straining. The safety is in the canner, the jar fill, and the process time.
What “Canning Vegetable Broth” Actually Means
Readers use “broth” and “stock” interchangeably here. For canning, the distinction that matters is not the name. It is what ends up in the jar.
Safe to process as broth: strained liquid only. It should pour like water or weak tea. Bits of herb or vegetable left behind change heat transfer.
Not the same product: broth with chunks, a purée, or anything thickened. That is soup, and soup has a different, longer process. USDA soup directions also cap how full the jar can be with solids and forbid pasta, rice, flour, cream, and other thickeners.
Keep those two projects separate. Can clear broth now. Add noodles, rice, or extra vegetables when you open the jar.
Why Pressure Canning Is Required
C. botulinum spores are common in soil and on vegetables. In a sealed jar they can grow and produce toxin if the food is low-acid (pH above 4.6) and never reaches about 240–250°F. A water bath tops out at 212°F. A pressure canner is what raises the temperature high enough to destroy the spores.
That is why Cooperative Extension answers the same question the same way: meat broth and vegetable broth both need a weighted-gauge or dial-gauge pressure canner. Substituting broth for water in a water-bath recipe also makes that product unsafe.
Three related methods that do not count as pressure canning:
- A boiling-water bath, no matter how long
- An Instant Pot or other electric multicooker used as a “canner”
- Adding lemon juice or vinegar to broth and then water-bathing it
Acid can make pickles and some tomato products safe for a water bath. It does not convert a pot of carrot-onion-celery liquid into a high-acid food you can treat like jam.
If you do not have a pressure canner, freeze the broth.
Why Vegetable Broth Times Differ From Meat Stock Times
This is the part most ranking pages leave muddy.
The National Center for Home Food Preservation publishes directions for meat stock (typically 20 minutes for pints and 25 minutes for quarts). It does not publish a separate, named vegetable-broth process. Extension agents have said as much when asked.
Ball and Bernardin do publish a vegetable-stock process: 30 minutes for pints (500 ml) and 35 minutes for quarts (1 L) at 10 pounds on a weighted-gauge canner at or below 1,000 feet, with pressure raised for altitude and for dial-gauge canners.
Use the longer vegetable-stock time for homemade vegetable broth. Two practical reasons:
- Vegetable broth is often made from a wider mix of scraps than a meat-stock recipe assumes. Starch and fine plant solids can change how heat moves through the jar.
- When two reputable sources disagree, the conservative tested time is the one that still matches a published vegetable-stock recipe.
Do not invent a hybrid. Do not use soup times (much longer) for a fully strained liquid, and do not drop to meat-stock times just because the jar looks “only liquid.”
| Product in the jar | Typical tested process (0–1,000 ft, weighted gauge) | Notes |
|---|---|---|
| Strained meat stock | 20 min pints / 25 min quarts | USDA/NCHFP meat-stock process |
| Strained vegetable stock/broth | 30 min pints / 35 min quarts | Ball / Bernardin |
| Vegetable soup with solids | Much longer (often 60 / 75 min) | Different product; solids limit applies |
Pressure, not time, is what you change with altitude.
What You Need
Equipment
- A stove-top pressure canner (dial-gauge or weighted-gauge), not a pressure cooker used off-label
- Pint or quart canning jars (quarts are the largest size with a tested process)
- New lids and matching bands
- Large stockpot
- Fine-mesh strainer plus cheesecloth or a flour-sack towel
- Jar lifter, funnel, and a headspace tool
- Clean cloth or paper towel for rims
Ingredients for a full canner load (about 7 quarts or 14 pints)
Ball-style vegetable stock is built on aromatic vegetables plus water. A typical batch looks like this:
- About 3 cups sliced carrots
- About 2 pounds onions, quartered (skins can stay on if they are clean)
- About 3 cups chopped celery, including leaves
- 2 bell peppers
- 2 large tomatoes, chopped
- A few garlic cloves
- Bay leaves, thyme, parsley, and peppercorns
- About 2 gallons of water
That formula is a flavor guide, not a chemistry lock. For safety, the jar must still hold strained, thin liquid. You can use a similar volume of clean scraps instead of a shopping list of whole vegetables.
Salt is optional. It seasons; it does not preserve.
Vegetables That Improve Broth vs. Vegetables That Cause Problems
Use freely: onion, leek, carrot, celery, parsley stems, garlic, mushroom stems, tomato, bell pepper, herb stems, corn cobs, clean peelings from those same vegetables.
Use sparingly or skip for quality: broccoli, cabbage, Brussels sprouts, cauliflower. They can turn the broth sulfurous and cloudy after a long simmer and a long process.
Leave out of canned broth: potatoes and other starchy vegetables that thicken the liquid. Starch changes heat penetration. If the broth looks like gravy, it is no longer the product those 30- and 35-minute times were written for.
Also skip anything spoiled, moldy, or heavily dirty. Scraps from the freezer are fine if they were clean when you froze them.
How to Make the Broth Before You Can It
- Wash vegetables. Rough-chop them. Peeling is optional because everything will be strained.
- Cover with water in a large pot. Bring to a boil, then drop to a bare simmer.
- Simmer about 2 hours covered, then uncover and cook until the flavor is where you want it. Bernardin’s published recipe simmers 2 hours covered and 2 hours uncovered. A shorter simmer still works if the broth tastes finished; a rolling boil makes it cloudy.
- Strain through a cheesecloth-lined colander into a clean pot. Press lightly if you want more yield, but do not force pulp through the cloth.
- Discard the solids. Reheat the strained broth to a full boil before filling jars.
If you started with frozen leftover broth, bring it back to a boil and strain it again. Cold or lukewarm liquid should not go into the jars.
A cloudy jar is usually a quality issue, not an automatic safety failure. Cloudiness comes from hard boils, starchy vegetables, and fine particles that slipped the strainer. Safety still depends on process, seal, and storage.
How to Pressure Can Vegetable Broth
Work hot-pack. Hot broth into hot jars into a hot canner reduces siphoning and helps the process start from a known temperature.
- Wash jars. Keep them hot. Wash lids in hot soapy water; follow the lid manufacturer on whether to simmer them.
- Put the canner rack in place and add the amount of water your manual specifies, usually 2 to 3 inches. Bring that water to a simmer.
- Ladle boiling broth into hot jars, leaving 1 inch of headspace.
- Remove air bubbles. Recheck headspace.
- Wipe rims clean. A little vinegar on the cloth helps if there is film on the glass.
- Apply lids and screw bands fingertip-tight. Do not crank them down.
- Load the canner. Lock the lid. Vent a strong stream of steam for 10 minutes before closing the vent or adding the weight. Trapped air lowers the temperature even if the gauge looks right.
- Bring the canner to the correct pressure for your altitude and canner type. Start the timer only when that pressure is reached.
- Process 30 minutes for pints, 35 minutes for quarts. If pressure drops, bring it back up and restart the timer.
- When time is up, turn off the heat. Let the canner return to zero pressure on its own. Wait a few minutes, then open the lid away from your face.
- Rest the jars in the canner for about 10 minutes, then move them to a towel with space between them. Leave them undisturbed 12 to 24 hours.
- Check seals, remove bands, wash the jars, label, and store.
Do not force-cool the canner with water or a cold draft. That is a common cause of siphoning and seal failure.
Pressure adjustments
Processing time stays 30 / 35 minutes. Pressure changes with altitude and gauge type.
Dial-gauge canner
- 0–2,000 ft: 11 lb
- 2,001–4,000 ft: 12 lb
- 4,001–6,000 ft: 13 lb
- 6,001–8,000 ft: 14 lb
- 8,001–10,000 ft: 15 lb
Weighted-gauge canner
- 0–1,000 ft: 10 lb
- Above 1,000 ft: 15 lb
Confirm your elevation and follow your canner manual if it is more specific.
Canning From Scraps vs. a Measured Recipe
A freezer bag of onion ends, carrot peels, celery leaves, and herb stems is how many people actually make vegetable broth. That is acceptable for canning if three conditions hold:
- The scraps were clean and sound when saved.
- The finished broth is fully strained and still thin.
- You use the vegetable-stock process above, not a guessed time.
What you cannot do is treat every scrap pot as a soup recipe, leave vegetables in the jar, and still use broth times.
If a batch tastes weak, reduce it a little before canning, but stop before it turns syrupy. If a batch tastes bitter, do not can it hoping the process will fix the flavor. Compost it and start with a cleaner mix.
Mistakes That Make Vegetable Broth Unsafe or Disappointing
Water-bath canning the jars. A seal only means the lid pulled down. It does not mean spores were destroyed.
Leaving solids in the jar and using broth times. Pieces of carrot or a ladle of pulp turn the product into soup.
Thickening before canning. Flour, cornstarch, potato, reduced paste, or commercial bases with starch and dairy do not belong in the jar.
Skipping the 10-minute vent. Air left in the canner gives a false sense of pressure.
Ignoring altitude. At higher elevations, 10 pounds on a weighted gauge is not hot enough.
Overfilling. Less than 1 inch of headspace encourages siphoning and weak seals.
Using half-gallon jars. There is no tested process for broth in jars larger than a quart.
Canning in an Instant Pot. USDA and Extension do not accept electric multicookers as pressure canners for low-acid food.
Assuming tomatoes made it high-acid. A couple of tomatoes in a two-gallon pot do not turn the whole batch into a water-bath product.
How to Store and Use Canned Vegetable Broth
Store sealed jars in a cool, dark, dry place. Quality is best within a year. The broth is still a canned low-acid food after that, but flavor fades.
Before opening, check the lid. A sealed lid is concave and does not flex. After opening, look and smell. Discard the jar without tasting if the lid is bulging, the seal has failed, the liquid spurts, the color is badly off, or the odor is wrong. Never taste from a suspect jar.
Home-canned low-acid food is often brought to a boil for 10 minutes after opening as an extra precaution; add a minute per 1,000 feet of altitude. That habit does not replace correct processing. It is a backup, not a repair kit for under-processed jars.
Use the broth anywhere you would use cartoned stock: soup, risotto, cooking liquid for grains, gravy, and pan sauces. Because homemade jars are usually milder and less salty than boxed broth, season in the pot rather than in the canner.
Pints are handy when a recipe wants 2 cups. Quarts save time when you make soup by the pot.
If You Do Not Want to Can It
Freezing is the correct alternative, not a weaker water-bath process.
Cool the strained broth, then freeze in straight-sided jars, freezer boxes, or bags. Leave headspace. Ice-cube trays or muffin tins work for small amounts. Frozen broth keeps quality for months; the limit is usually freezer space, not safety.
You can later thaw, boil, and pressure-can that same broth if you want pantry jars.
Frequently Asked Questions
Can I water bath can vegetable broth if I process it for hours? No. Time at 212°F does not replace temperature at 240°F.
Can I add vinegar or lemon juice and then water-bath it? No. Added acid is not a tested substitute for pressure canning this product.
Is scrap broth safe to can? Yes, if it is strained thin and processed as vegetable stock in a pressure canner. Safety follows the fill and the process, not whether the vegetables started as scraps or whole produce.
Why do some sites say 20 and 25 minutes? Those are meat-stock times. Ball and Bernardin use 30 and 35 for vegetable stock. Use the vegetable-stock times.
Can I can broth in an Instant Pot? Not safely. Use a pressure canner built and tested for canning.
Do I have to add salt? No.
Can I leave vegetables in the jar? Not with broth processing times. That is soup, and soup has different rules.
What if a jar doesn’t seal? Refrigerate and use soon, or freeze it. You can reprocess within 24 hours with a new lid only if the broth is still sound and you repeat the full pressure process. Reprocessing hurts quality.
How long does canned vegetable broth last? Plan on a year for best flavor. Check every jar before you use it.
Canning vegetable broth is worth doing when you already simmer scraps and you own a pressure canner. The recipe can flex. The method cannot: strained liquid, hot pack, 1 inch headspace, 30 minutes for pints, 35 minutes for quarts, pressure matched to your altitude. Follow that, and the jars on the shelf are a pantry staple rather than a guess.