Trim stems and discolored parts of mushrooms. Soak mushrooms in cold
water for 10 minutes to remove adhering soil. Wash in clean water. Leave
small mushrooms whole; cut larger ones in halves or quarters. Steam 4
minutes or heat gently for 15 minutes without added liquid in a covered
saucepan.
_In glass jars._—Pack hot mushrooms to ½ inch of top. Add ¼ teaspoon
salt to half pints; ½ teaspoon to pints. For better color, add
crystalline ascorbic acid—¹/₁₆ teaspoon to half-pints; ⅛ teaspoon to
pints. Add boiling-hot cooking liquid or boiling water to cover
mushrooms, leaving ½-inch space at top of jar. Adjust jar lids. Process
in pressure canner at 10 pounds pressure (240° F.)—
Half-pint jars 30 minutes
Pint jars 30 minutes
As soon as you remove jars from canner, complete seals if necessary.
_In tin cans._—Pack hot mushrooms to ¼ inch of top of cans. Add ½
teaspoon salt to No. 2 cans. For better color, add ⅛ teaspoon of
crystalline ascorbic acid to No. 2 cans. Then fill to top with
boiling-hot cooking liquid or boiling water. Exhaust to 170° F. (about
10 minutes) and seal cans. Process in pressure canner at 10 pounds
pressure (240° F.)—