Michigan
State University Extension
Preserving
Food Safely - 01600854
10/13/97
GUIDE 5:12
TUNA
Tuna may be canned either precooked or raw. Precooking
removes most of the strong-flavored oils. The strong
flavor of dark tuna flesh affects the delicate flavor of
white flesh. Many people prefer not to can dark flesh.
It may be used as pet food.
Note: Glass-like crystals of magnesium ammonium
phosphate sometimes form in canned tuna. There is no way
for the home canner to prevent these crystals from
forming, but they usually dissolve when heated and are
safe to eat.
PROCEDURE: Keep tuna on ice until ready to can. Remove
viscera and wash fish well in cold water. Allow blood to
drain from stomach cavity. Place fish belly down on a
rack or metal tray in the bottom of a large baking pan.
Cut tuna in half crosswise, if necessary. Precook fish
by baking at 250 degrees F for 2-1/2 to 4 hours
(depending on size) or at 350 degrees F for 1 hour. The
fish may also be cooked in a steamer for 2 to 4 hours.
If a thermometer is used, cook to a 165 degrees F to 175
degrees F internal temperature. Refrigerate cooked fish
overnight to firm the meat. Peel off the skin with a
knife, removing blood vessels and any discolored flesh.
Cut meat away from bones; cut out and discard all bones,
fin bases, and dark flesh. Quarter. Cut quarters
crosswise into lengths suitable for half-pint or pint
jars. Fill into jars, pressing down gently to make a
solid pack. Tuna may be packed in water or oil,
whichever is preferred. Add water or oil to jars,
leaving 1-inch headspace. Add 1/2 teaspoon of salt per
half-pint or 1 teaspoon of salt per pint, if desired.
Adjust lids and process.
Recommended process time for TUNA in a dial-gauge
pressure canner.
Canner Gauge Pressure (PSI)
at Altitudes of
Jar Process 0- 2,001- 4,001- 6,001-
Size Time 2,000 ft 4,000 ft 6,000 ft 8,000 ft
Half-
pints 100 min 11 lb 12 lb 13 lb 14 lb
or Pints
Recommended process time for TUNA in a weighted-gauge
pressure canner.
Canner Gauge Pressure (PSI)
at Altitudes of
Jar Process 0- Above
Size Time 1,000 ft 1,000 ft
Half-
pints 100 min 10 lb 15 lb
or Pints