Michigan State University Extension
Preserving Food Safely - 01600580
A number of simple serviceable smokehouses can be built at home. Similar procedures are used with most smokehouses. Follow manufacturer's instructions for commercially built smokers.
Place fish in the smokehouse. Clear all combustible material from around and under the smoking area. Form a small bed of coals on the hot plate for a small fire. Take care to keep it from flaring up. Cover the coals with dry hardwood chips. Use only hardwoods, because softwoods, moss and leaves may leave unpleasant tastes in the fish. To prevent chips from flaming, lightly dampen chips with water. Add chips as needed to keep the smoke dense throughout the process, and regulate draft by the vents or by raising or lowering the lid or side of the chamber.
Cold smoke (90 to 100 degrees Fahrenheit) for 2 to 3 hours, then gradually add hot coals to the smoker to raise the temperature of the smokehouse to 225 degrees Fahrenheit. Maintain this temperature until the internal temperature of the fish reaches 180 degrees Fahrenheit which should take 3 or 4 hours. Hold the fish at the 180 degrees Fahrenheit flesh temperature for 30 minutes. Insert a thermometer into the thickest part of the fish to be sure all the flesh reaches this temperature. Whole fish also need to be smoked and cooked thoroughly. The total time required may be as much as 12 hours for whole fish.
When smoking is completed, remove the fish and allow them to cool. Keep fish protected from dust and insects; then wrap in waxed paper or plastic wrap, and refrigerate. Use smoked fish within 14 days.