Imitation crab is a seafood product made from surimi (a Japanese word that literally means ground meat) or Asian fish paste, and is known as Krab in the United States.
Krab is sold in chunks or sticks and is usually found in the fresh seafood section of most grocery stores. It can be used in a variety of dishes, from salads and stir-fries to dips and appetizers.
The process for making surimi was developed in Eastern Asia over several centuries though the exact history and origins of this product are unclear. Industrial technology developed by Japan in the early 1960s promoted the growth of the surimi industry, and its industrialized production was refined in 1969 by Nishitani Yōsuke of Japan’s Hokkaidō Fisheries Experiment Institute to revitalize Japan’s growing fish industry by improving processing efficiency and better utilize fodder fish.
The United States and Japan are the world’s top two producers of this popular fish alternative. Thailand and China have also become important producers, and Lithuania, Vietnam, Chile, the Faroe Islands, France, and Malaysia are emerging as industry newcomers.
Three to four million tons of fish from around the world are used for the production of surimi and surimi-based products each year. The traditional fish of choice is Alaskan Pollock. However, as the availability of Alaskan Pollock has declined over the years, other species including Walleye Pollock, Atlantic Cod, Big-Head Pennah, Croaker, Bigeyes, Golden Threadfin Bream, Milkfish, Pacific Whiting, Shark, Swordfish, Tilapia, Florida Black Bass, Smallmouth Bass, Largemouth Bass and New Zealand Hoki now supplement global surimi production. These specific species are used because of their plentiful numbers, and because they each have relatively little flavor. This allows the meat to be effectively influenced by flavoring agents and aromas.
The production and refining process of surimi:
- The fish are sorted by size and species.
- After sorting, the fish are filleted – a step in which the head, tail, fins, bones and scales are removed.
- The fillets are then minced, or cut into very small pieces and thoroughly rinsed with cold water to remove small unwanted parts, any remaining scales, fat and inorganic salt.
- The refining process continues by dividing the fish into two groups: white, softer meat and dark, harder meat.
- The separated meat is pressed to remove superfluous water after which sugar and sorbitol are added to make sure that the proteins of the fish are not damaged when frozen. The additives also ensure that the finished product will have a good flavor and a longer storage life.
- After mixing, the surimi is packed in large polyethylene bags and fast frozen to a temperature of 20°C below zero. This fast freezing process damages the fish meat less than slow freezing because it creates small internal ice crystals as opposed to large ones. The fish is kept at this temperature until it can be further processed in a few days or a few weeks.
- When the processing continues, the surimi is heated to a temperature of 4°C below zero. This temperature is high enough to obtain good cutting surfaces, but it is low enough to avoid the growth of microorganisms.
- The pieces of surimi are then mixed with an assortment of additives that usually includes egg whites, oils, salt, starches, and spices, along with various artificial flavorings, sodium and monosodium glutamate, or MSG.
- The mixture is shaped into chunks or tubes and cut into long blocks or sticks called bars. The bars are cooked for a few minutes to set the shape and to give them a texture closer to real crab meat.
- The bars are then rapidly cooled down to a temperature of 3°C below zero.
- The cold bars are cut into small pieces that are coated with a reddish food coloring to give them a pink tint like real crab.
- The cut and colored bars are vacuum-packed in bags and pasteurized by steam to kill vegetative microorganisms thereby increasing storage life.
- With a stocking temperature of 3°C, the bars have a storage life of one to two weeks.
Nutritionally, imitation crab has a number of plusses and minuses:
- Imitation crab is relatively low in calories — even a generous 6-ounce portion contains just 162 calories – with almost two-thirds of those calories coming from its carbohydrate content of 25.5 grams per serving. Consuming 6 ounces of imitation crab will boost your protein intake by 13 grams but drop your fiber intake to only 0.8 of a gram.
- That same 6-ounce portion of imitation crab offers 0.22 milligrams of vitamin B-6 and 0.97 micrograms of vitamin B-12.
- Your serving of imitation crab also contains two essential minerals: 479 milligrams of phosphorus and 38 micrograms of selenium.
- Imitation crab has two major nutritional drawbacks — its sugar and salt content. Each serving of imitation crab contains 10.6 grams of sugar (which improves its flavor, but increases your calorie intake) and 899 milligrams of sodium.
In Asian cultures, fried, steamed and boiled surimi is eaten as a food in its own right and seldom used to imitate other foods. In Japan, fish cakes (kamaboko) and fish sausages, as well as other extruded fish products, are commonly sold as cured surimi. In Chinese cuisine, fish surimi, often called “fish paste”, is used directly as stuffing or made into balls. In the West, surimi products are usually imitation seafood products, such as crab, abalone, shrimp, calamari, and scallops. Surimi is also used to make kosher imitation shrimp and crabmeat, using only kosher fish such as Pollock.