Smoked fish is similar throughout the world as a means of preservation where climate extremes or transportation can be a problem. Preservation can be accomplished by first cutting the flesh into thin strips and then drying them slowly over a fire – or in the sun in northern climates. The modern day approach is to use an electric food dehydrator as is used for making jerky.
Dried smoked products can travel great distances and remain edible for long periods of time. Drying is the critical factor for preservation, because it is moisture in the flesh that permits bacterial activity and spoilage. Salt can be used to accelerate the removal of water and hence its widespread use as a traditional preservative. The act of smoking fish imparts extracts from the smoke (phenols, etc.) that retards the development of spoilage bacteria.
During the Middle Ages in Europe heavily smoked and salted foods were relied upon as a food source in late winter and into spring survival food . Fresh fish could not be transported from the port of landing unless they were preserved. Red Herring and Salt Cod still made toady was a staple of the times. Heavily salted herring was smoked for up to three weeks in a kiln to make Red Herring. The kipper for example was invented by John Woodger about 1843. Within a few years it became very popular and remains so today.
Fish for smoking must be fresh and have a relatively low fat content. The fat or oils found in fish can go rancid over time. Some fish keep longer than others. Trout and salmon for instance, will keep longer than mackerel. After preparation the fish is either brined or packed in fine dry salt (brining being more common nowadays). Brining or salting is a way of increasing the moisture holding capacity of meat resulting in a moister product when it is cooked.
A brine is basically a salt solution into which you place your fish. Brine your fish with this basic brine solution:
• 1/2 cup non-iodized salt
• 1/2 cup sugar
• 1 quart water
Stir until completely dissolved. Place fish in the brine, being careful to ensure that the fish is completely covered with the brine and place in the refrigerator. If the fish is in thick chunks of 1 inch or more put in brine for 8 to 12 hours, if thinner put in brine for 6 to 8 hours. Remove fish from brine and rinse each piece under cold water.
Gently pat the fish dry and lay pieces on a rack to air dry for one hour. When the fish is sticky to the touch it is ready to be smoked.
Smoke the fish for about 2 hours at 200°F. Use your favorite wood chips or chunks when smoking and experiment to find the taste that you like best. Hickory, Alder, Apple and Cherry or combinations of these work well. Add wood chips about every 30 minutes if necessary (depending on how much smoke taste you want.
The smoking process should allow excess liquid to drain off and allows the formation of an attractive gloss. The gloss is formed from the drying of a water soluble protein that forms a pellicle.
Most fish is cold-smoked, meaning that the temperature of the smoking process is not allowed to exceed 34°C. Cold smoked products include Lox, cod and Kippers. Hot smoking on the other hand, is the slow raising of the temperature to in excess of 140°F to cook the product. Mackerel, Shrimp, Scallops and Salmon are typically hot smoked. These products are generally flaky in texture and are ready-to-eat.