Michigan
State University Extension
Preserving
Food Safely - 01600496
10/13/97
These canners are made of aluminum or porcelain-covered
steel. They have removable perforated racks and fitted
lids. The canner must be deep enough so that at least 1
inch of briskly boiling water will be over the tops of jars
during processing. Some boiling-water canners do not have
flat bottoms. A flat bottom must be used on an electric
range. Either a flat or ridged bottom can be used on a gas
burner. To ensure uniform processing of all jars with an
electric range, the canner should be no more than 4 inches
wider in diameter than the element on which it is heated.
(Using Boiling-Water Canners)
Follow these steps for successful boiling-water
canning:
1. Fill the canner halfway with water.
2. Preheat water to 140 degrees Fahrenheit for
raw-packed foods and to 180 degrees Fahrenheit
for hot-packed foods.
3. Load filled jars, fitted with lids, into the
canner rack and use the handles to lower the rack
into the water; or fill the canner, one jar at a
time, with a jar lifter.
4. Add more boiling water, if needed, so the water
level is at least 1 inch above jar tops.
5. Turn heat to its highest position until water
boils vigorously.
6. Set a timer for the minutes required for
processing the food.
7. Cover with the canner lid and lower the heat
setting to maintain a gentle boil throughout the
process schedule.
8. Add more boiling water, if needed, to keep the
water level above the jars.
9. When jars have been boiled for the recommended
time, turn off the heat and remove the canner
lid.
10. Using a jar lifter, remove the jars and place them
on a towel, leaving at least 1-inch spaces between
the jars during cooling.