Do the Math
Jars & Pounds
How many jars, canner loads and pounds of produce your family needs.
Preserving Calculators →Preserving Basics
Water-bath and pressure canning, freezing, drying and cold storage — and the simple rules that keep your family safe.
Water-bath canning — high-acid foods
- For fruits, jams and jellies, pickles, and tomatoes with added lemon juice or citric acid.
- Jars sit on a rack covered by 1–2 inches of boiling water for the full process time.
- Add time at higher altitude — the calculators do this for you.
Pressure canning — low-acid foods
- Required for vegetables, beans, meat, poultry, broth and fish. Boiling water can’t reach the 240°F needed to destroy botulism spores.
- Vent the canner 10 minutes before adding the weight, and let it cool down on its own.
- Have a dial gauge tested every year. Use more pressure at higher altitude.
Rules that keep your family safe
- Use only tested recipes and times — from the USDA Complete Guide to Home Canning, the National Center for Home Food Preservation (nchfp.uga.edu), Ball, or your extension office. Old family recipes and online guesses are not tested.
- Never can mashed squash or pumpkin, flour-thickened sauces, wild mushrooms, or garlic or herbs in oil at home.
- Use new lids each time, leave the headspace the recipe gives, and wipe the rims before closing.
- After 12–24 hours, check every lid has sealed. Store sealed jars without rings in a cool, dark place and use within a year.
- If a jar is bulging, leaking, spurting or smells off, don’t taste it — throw it out where children and animals can’t reach it.
Freezing
- Blanch most vegetables first to stop the enzymes that dull colour and flavour, then cool quickly in ice water.
- Pack in freezer bags or containers with the air pressed out, and label with the date.
- Keep the freezer at 0°F. Most produce is best within 8–12 months.
Drying
- Vegetables dry at about 125°F, fruits at 135°F, and herbs at 95–100°F.
- Dried food should be leathery or crisp with no moisture when cut. Condition fruit in a closed jar for a week, shaking daily.
- Store in airtight jars in a cool, dark place.
Root cellar & cold storage
- Potatoes, carrots, beets, cabbage, apples and winter squash keep for months in the right spot — cool and humid for roots, cool and dry for squash, onions and garlic.
- Store apples apart from potatoes and other vegetables — the gas they give off makes others sprout or spoil.
Share What You Put Up
Have a question about a recipe, a seal that didn’t take or how long something keeps? Ask in the Food Preservation group — and please share tested recipes so everyone’s pantry stays safe.