Putting Food By - Janet Greene [83]
Specific Seafood Products
Salmon and Shad
Pressure Canning only. Use Raw pack and exhaust. Use pint jars (preferably straight-sided) with two-piece screwband lids only. Glassy crystals of magnesium ammonium phosphate usually occur in salmon canned at home. They are harmless and generally dissolve when the fish is reheated for serving.
Twenty-five pounds of round fish (i.e., whole and not dressed) will fill about twelve 1-pint jars.
Remove the head, tail, fins, and scales and scrub perfectly fresh fish; cut away the thin belly flap. Split the fish in half lengthwise if very large. You may leave the bones in these fish because the bones become very soft in processing. (In any case, shad is extremely difficult to bone unless you are an expert.) Using a jar laid on its side as a measure, cut the fish across the grain in jar-length pieces—and not one whit longer lest they interfere with the seal (the fish will shrink in the jar to leave headroom). Prepare a cold brine of ¾ cup pure pickling salt dissolved in 1 gallon of ice-cold water, an amount of brine that will do 25 pounds of prepared fish. Use enameled, stainless steel, or non-metal tubs; use brine only once. Weight the fish pieces down in the brine and refrigerate for 60 minutes to draw out diffused blood and firm the flesh. Drain the pieces for 10 minutes; do not rinse.
Fill the jars solidly and in effect just to the top—this means no more than inch below the sealing rim—packing the pieces upright, skin side next to the glass, and carefully inserting slimmer pieces to fill vertical gaps. Don’t pack the pieces so tight that they spring back and hurt the seal.
Next, half-close the filled jars. To do this, place the flat lid on the sealing rim of the jar, and screw the band down just until the band cannot be pulled up off the threads. (Practice on an empty jar to get the feel of this half-closure.) Exhaust the jars in the Pressure Canner at Zero pounds (as described in General Handling above); after 15 minutes, open the canner, then open one jar and test the center of its contents with your thermometer. By this time it should read at least 170 F/77 C; if not, give it 5 minutes more.
When jars are exhausted, lift the canner off heat and finish screwing the bands firmly tight as for any processing. Return the canner to heat, put on the lid and let steam vent in a strong, steady flow for 10 minutes before closing the petcock/vent and starting to time the processing period. The amount of very hot water remaining in the canner after exhausting the jars should be ample for Pressure-processing.
Pressure-process at 10 pounds (240 F/116 C) for 1 hour and 50 minutes. Remove jars; air-cool naturally.
• Adjustment for my altitude_________________.
Tunas, Large and King Mackerel
Glassy crystals of magnesium ammonium phosphate may form in tuna canned at home. No worries: they are safe to eat, and actually may dissolve when contents are heated.
Pressure Canning only. Precook completely, cool, then exhaust. Use only ½-pint jars with two-piece screwband lids.
Estimate 12½-pint jars for every 25 pounds of round fish. Dress and scrub the fish; cut away the thin belly flap. Cut fish crossways in good-size chunks (it will be cut for the jars after it’s precooked).
For the precooking stage you will need several large round pans with perforated bottoms that can be stacked inside your Pressure Canner. Put 2½ to 3 inches of hot water in the canner; put a perforated support on the bottom of the canner—a wire cake rack, laid on some retired screwbands to help it take the weight of the fish; or an inverted metal pie pan with holes punched in its bottom; stack the pan-loads of fish in the canner. Put the lid on the canner; vent it (a strong, steady flow for 10 minutes); close the vent and Pressure-cook the fish at 10 pounds (240 F/116 C) for 2 hours. Alternatively, you may bake the fish at 350 F/177 C until it reaches an internal temperature of 170 F/77 C, about 1 hour.