Pressure canning times for vegetables: the USDA chart
How long to pressure can green beans, corn, potatoes, carrots and every vegetable in the USDA guide, with headspace and the pressure for your altitude.
With Jarwise
Water bath vs pressure canning: which foods need which
Short answer
Low-acid foods (all vegetables, meat, poultry, seafood and soups) must be pressure canned: only a pressure canner gets hot enough to destroy the spores of *Clostridium botulinum* in them. The USDA guide gives no water-bath time for any of them, so green beans, potatoes and corn can't be water-bath canned.
Fruits and acidified tomatoes can go in a boiling-water bath, and many also have a tested pressure-canner option at lower pressures. Use the time for the method you choose; never move a time from one method to the other.
Which canner the guide gives, by kind of food
Counted from the guide's own tables (the build checks that no low-acid food has a water-bath time).
| Kind of food | Foods in the guide | Low-acid | Canner the guide gives |
|---|---|---|---|
| Vegetables | 19 | 19 | Pressure canner only |
| Meat and poultry | 6 | 6 | Pressure canner only |
| Seafood | 7 | 7 | Pressure canner only |
| Soups | 2 | 2 | Pressure canner only |
| Tomatoes | 8 | 1 | Water bath for 7 of 8; a pressure option for 8 of 8 |
| Tomato sauces | 8 | 3 | Water bath for 5 of 8; a pressure option for 3 of 8 |
| Fruit | 16 | 0 | Water bath for 16 of 16; a pressure option for 10 of 16 |
| Fruit juices | 2 | 0 | Water bath only |
Counted from the USDA Complete Guide to Home Canning (2015) tables as transcribed in Jarwise. Low-acid foods never get a water-bath time.
How the two methods differ
- Boiling-water bath: jars covered by at least 1 inch of water (2 inches for processes over 30 minutes), timed from a full rolling boil with the lid on. If the boil stops, bring it back and time the whole process again. When done, turn off the heat, take the lid off and wait 5 minutes before lifting the jars out (Guide 1, page 1-18).
- Pressure canner: 2 to 3 inches of water, vent steam for 10 minutes, then time at the pressure for your altitude and gauge. If the pressure drops below it, bring it back and time the whole process again. Let the canner come down to zero on its own (Guide 1, pages 1-20 and 1-21).
- Altitude: both methods change with altitude, the water bath by longer times, the pressure canner by higher pressure (Guide 1, page 1-22).
Why low-acid foods need pressure
Botulinum spores survive the temperature of boiling water. In the sealed, airless jar of a low-acid food they can grow and make toxin. A pressure canner raises the temperature enough to destroy them in the tested time. That's why the guide gives low-acid foods pressure-canner times only, and why tomatoes need added acid even in a water bath (Introduction; Guide 1, page 1-8).
Methods the guide warns against
Open-kettle canning (filling hot jars without processing them) and processing jars in an oven, a microwave or a dishwasher don't prevent all risks. Use a boiling-water or pressure canner with a tested time (Guide 1, page 1-10).
Questions
Can you water bath green beans?
No. Green beans are a low-acid vegetable; the USDA guide gives them pressure-canner times only (20 minutes for pints, 25 for quarts).
Can you water bath potatoes or corn?
No. Like all vegetables they are low-acid and must be pressure canned with a tested time.
Can you pressure can tomatoes instead of using a water bath?
Yes. The guide tests pressure-canner options for several tomato products at lower pressures, with acid still added to every jar.
Can you water bath chicken broth or meat?
No. Meat, poultry, broth and seafood are low-acid and have pressure-canner times only.
Is a pressure cooker the same as a pressure canner?
No. The guide's times are tested in pressure canners that hold the jars and keep the pressure for the whole process; don't use them in another kind of appliance.
Jarwise: Canning Timer & Log
Canning app: USDA-tested times for your altitude, canner timer, jar log.
Jarwise has every tested food in the USDA guide. Set your altitude once and it shows the right time and pressure for your canner, with your altitude band highlighted; combinations the guide doesn't test get no time. A step-by-step timer covers venting, processing and cool-down, and a batch log and pantry keep track of your jars, offline and with no account.
Coming to Google Play
Sources
- USDA Complete Guide to Home Canning (2015), Introduction (Caution; For safety's sake) Introduction (PDF)
- USDA Complete Guide to Home Canning (2015), Guide 1: Principles of home canning (pages 1-8, 1-10, 1-13, 1-18 to 1-22) Guide 1 (PDF)
- USDA Complete Guide to Home Canning (2015), Guide 3: Tomatoes and tomato products (acidification, page 3-5) Guide 3 (PDF)
- USDA Complete Guide to Home Canning (2015), Guide 4: Vegetables and vegetable products Guide 4 (PDF)
- National Center for Home Food Preservation: the USDA Complete Guide to Home Canning, 2015 revision (current edition) nchfp.uga.edu
More guides
All guidesHow long to water bath tomatoes, tomato juice and sauce
Water-bath times for whole, crushed and juiced tomatoes and tomato sauce by altitude, the acid every jar needs, and the pressure options, from the USDA guide.
With Jarwise
Canning altitude adjustment chart: water bath and pressure
How altitude changes home canning: longer water-bath times by altitude band, and higher pressure for weighted and dial gauges, from the USDA guide.
With Jarwise
Pressure canning times for meat, chicken and broth
How long to pressure can meat chunks, ground meat, chicken with or without bones and meat stock, with headspace and the pressure for your altitude (USDA).
With Jarwise