Pacific Northwest PNW 421 Using Manual - Peratures
Three serious errors in maintaining proper tem-
peratures
1. Internal canner temperatures are lower at higher alti-
tudes and can result in underprocessing. To correct
for altitude, operate canners at the increased pres-
sures specified below for altitude ranges above
1,000 feet:
Weighted-gauge pressure canner
Sea level to 1,000 feet—use 10-pound weight
Above 1,000 feet—use 15-pound weight
Dial-gauge pressure canner
Sea level to 2,000 feet—11 pounds pressure on dial
2,001-4,000 feet—12 pounds pressure on dial
4,001-6,000 feet—13 pounds pressure on dial
6,001-8,000 feet—14 pounds pressure on dial
2. Air trapped in a canner lowers the temperature and
results in underprocessing. The highest volume of
trapped air occurs in processing raw packed foods in
dial-gauge canners. These canners do not vent air
during processing. To be safe, vent all types of pres-
sure canners for 10 minutes before pressurizing them.
3. Dial gauges can be inaccurate. Have your dial
gauge checked each year before use.
Storing your pressure canner
Before storing your canner, make sure it is clean and
dry. Air should reach the inside of the canner to prevent
a stale odor from forming. Put crumpled papers inside
the canner. Wrap the lid in paper or place it in a paper
bag.
Turn the lid upside down in the canner instead of seal-
ing the canner shut. If storage space is available, place
the lid in a paper bag and store it right side up on a
shelf.
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