The two methods of packing, food into canning jars are raw pack and hot pack.
Raw pack is packing raw, prepared food into clean, hot jars and then
adding hot liquid. Fruits and most vegetables need to be packed tightly because
they will shrink during processing. However, raw corn, lima beans, and peas
should be packed loosely, as they will expand. For hot pack, heat
prepared food to boiling, or partially cook it. It should be packed loosely
boiling, hot into clean, hot jars. Hot pack takes more time but has been found
to result in higher quality canned foods.
For either packing, method, pack acid foods including tomatoes and acidified
figs to within ½-inch of the top of the jar. Low acid foods to within 1 inch of
the top of the jar.
After food is packed into jars, wipe the jar rims clean. Put on the lid with
the sealing compound next to the jar rim. Screw the band down firmly so that it
is hand-tight. Do not use a far wrench to tighten screw bands. There must be
enough "give" for air to escape from the jars during, processing. Process food
promptly after packing it into jars and adjusting lids. Processing times are
given for pints and quarts. If you are using half pint jars, use processing
times for pints. For one-and-one-half pint jars, use processing times for
quarts. Fruit juices are the only product that may be canned in half gallon
If you live at an altitude of more than 1,000 feet, you will
need to modify the processing time for acid foods and the pounds pressure you
use to process low-acid foods. The processing instructions presented in this
bulletin are for altitudes of 0-1000 feet. To determine your altitude, contact
the North Carolina Geological Survey Office. Their address is: 512 North
Salisbury Street, P.O. Box 27687, Raleigh, NC 2761 1. Their telephone number is
919-733-2423. After determining your altitude, your local extension center can
help you to determine changes you need to make to your canning instructions.
Use a water bath canner to process acidified tomatoes,
acidified figs and all other fruits. A pressure canner can be used to process
acid foods but the quality will not be as good.
- Fill the canner half full with water; then cover and heat. For raw-packed
food, have the water hot but not boiling. For hot-packed food, have the water
- Using a far lifter, place jars filled with food on the rack in the canner.
If necessary, add boiling water to brine, water 1 to 2 inches over the tops of
the jars. Do not pour boiling, water directly on jars. Cover.
- When water comes to a rolling boil, start counting the processing
time. Keep water at a boil for the entire processing time. Add more
boiling water to keep water I to 2 inches above jars.
- As soon as the processing time is up, use a jar lifter to remove jars from
canner. If liquid boiled out of the jars during processing, do not open them
to add more. Do not retighten screw bands, even if they are noticeably
If you live at an altitude of 0-1000 feet you can process foods
in a weighted gauge pressure canner at 10 pounds pressure. If you are using, a
dial gauge pressure canner, use 11 pounds pressure. If you live at an altitude
more than 2,000 feet you need to increase the pounds pressure at which you
process foods. These increases are not given in this bulletin. Contact your
county extension center to get this information. If tomato products are
acidified, they can be safely processed in a water bath canner. If not, they
must be processed in a pressure canner.
Here are some pointers for using a pressure canner:
- Pour 2 or 3 inches of water in the bottom of the canner and heat to
- Set jars on the rack in the canner. If you have two layers of jars in the
canner, use a rack between them and stagger the second layer.
- Fasten the canner cover securely so steam cannot escape except through the
- Once steam pours steadily from vent, let it escape for 10 minutes to drive
all air from the canner. During, processing, the canner must be filled with
steam, not air, since it is steam that reaches the desired temperature of
- If the canner has a weighted gauge, start counting the processing time
when it jiggles or rocks. The target pressure for this type of canner is 10
pounds pressure. Adjust heat so that gauge jiggles 2 or 3 times a minute or
maintains a slow, steady , rocking motion.
- If the canner has a dial gauge, bring pressure up quickly to 8 pounds,
then adjust the heat to maintain 11 pounds pressure. Start counting the
processing times when the gauge registers 11 pounds pressure.
- When the processing time is up, turn off the burner. (If you are using, a
coal or wood stove, remove canner from heat.) Let the pressure in the
canner drop to zero by itself. This may take 45 minutes in a 16-quart
canner filled with jars and almost an hour in a 22-quart canner. If the vent
is opened before the pressure drops to zero or if the cooling is rushed by
running, cold water over the canner, liquid will be lost from the jars.
- When the pressure has dropped to zero, open the vent or remove the
weighted gauge. (With a weighted gauge canner, pressure is completely reduced
if no steam escapes when the gauge is nudged or tilted. If steam spurts out,
pressure is not yet down.)
- Remove canner cover carefully, tilting it away from your face so that the
rising steam cannot burn your face or hands.
- Remove jars from canner. If liquid boiled out of jars during processing,
do not open jars to add more liquid. Do not retighten screw bands, even
if they are noticeably loose.
- Place hot jars upright to cool on a towel or rack. Leave space between
them so air can circulate. Keep jars our of drafts.
Vacuum seals form as the jars cool. When jars are cool (12 to
24 hours after processing), check the seals. If the lid is depressed or
concave and will not move when pressed, it is sealed. If sealed, carefully
remove screw bands. If a band sticks, loosen it by covering, it for a moment
with a hot, damp cloth. Bands left on jars during storage may rust, making
later removal difficult.
If you find an unsealed jar, do one of the following:
- Refrigerate the food and use it within 2 to 3 days.
- Freeze the food. (Drain vegetables before freezing.)
- Reprocess the food. Remove lids, empty the contents in to a pan, heat to
boiling, pack into clean, hot jars, and put on new lids. Process again for
the full time.
The eating quality of twice-processed food may be poor. If more than 24
hours have gone by since processing, throw out the food. It might be unsafe to
Label sealed jars with the processing date. Store them in a cool, dry, dark
place. Properly stored canned foods will retain their quality for at least a
year. Never store canned foods near hot pipes, a range, a furnace, or in
direct sunlight because they lose quality.
If stored in a cold place, protect from freezing by wrapping a the jars in
newspaper or covering them with a blanket. Canned foods that do freeze may be
used as long as freezing does not break the seal. However, they may not be as
tasty as properly stored canned foods.
If canned foods are kept in a damp place, lids may rust.
The Icons below will guide you to more information on Canning. Recipes will be found on pages 4 and above.