Seafood
Seafood is any form of sea life regarded as food by humans, prominently including fish and shellfish. Shellfish include various species of molluscs, crustaceans, and echinoderms. Historically, marine mammals such as cetaceans as well as seals have been eaten as food, though that happens to a lesser extent in modern times. Edible sea plants such as some seaweeds and microalgae are widely eaten as sea vegetables around the world, especially in Asia.
Seafood is an important source of protein in many diets around the world, especially in coastal areas. Semi-vegetarians who consume seafood as the only source of meat are said to adhere to pescetarianism. The harvesting of wild seafood is usually known as fishing or hunting, while the cultivation and farming of seafood is known as aquaculture and fish farming. Most of the seafood harvest is consumed by humans, but a significant proportion is used as fish food to farm other fish or rear farm animals. Some seafoods are used as food for other plants. In these ways, seafoods are used to produce further food for human consumption. Also, products such as fish oil, spirulina tablets, fish collagen, and chitin are made from seafoods. Some seafood is fed to aquarium fish, or used to feed domestic pets such as cats. A small proportion is used in medicine or is used industrially for nonfood purposes.
History
The harvesting, processing, and consuming of seafoods are ancient practices with archaeological evidence dating back well into the Paleolithic. Findings in a sea cave at Pinnacle Point in South Africa indicate Homo sapiens harvested marine life as early as 165,000 years ago, while the Neanderthals, an extinct human species contemporary with early Homo sapiens, appear to have been eating seafood at sites along the Mediterranean coast beginning around the same time. Isotopic analysis of the skeletal remains of Tianyuan man, a 40,000-year-old anatomically modern human from eastern Asia, has shown that he regularly consumed freshwater fish. Archaeology features such as shell middens, discarded fish bones, and cave paintings show that sea foods were important for survival and consumed in significant quantities. During this period, most people lived a hunter-gatherer lifestyle and were, of necessity, constantly on the move. However, early examples of permanent settlements, such as those at Lepenski Vir, were almost always associated with fishing as a major source of food.The ancient river Nile was full of fish; fresh and dried fish were a staple food for much of the population. The Egyptians had implements and methods for fishing and these are illustrated in tomb scenes, drawings, and papyrus documents. Some representations hint at fishing being pursued as a pastime.
Fishing scenes are rarely represented in ancient Greek culture, a reflection of the low social status of fishing. However, Oppian of Corycus, a Greek author wrote a major treatise on sea fishing, the Halieulica or Halieutika, composed between 177 and 180. This is the earliest such work to have survived to the modern day. The consumption of fish varied by the wealth and location of the household. In the Greek islands and on the coast, fresh fish and seafood were common. They were eaten locally but more often transported inland. Sardines and anchovies were regular fare for the citizens of Athens. They were sometimes sold fresh, but more frequently salted. A stele of the late 3rd century BCE from the small Boeotian city of Akraiphia, on Lake Copais, provides us with a list of fish prices. The cheapest was skaren whereas Atlantic bluefin tuna was three times as expensive. Common salt water fish were yellowfin tuna, red mullet, ray, swordfish, or sturgeon, a delicacy that was eaten salted. Lake Copais itself was famous in all of Greece for its eels, celebrated by the hero of The Acharnians. Other freshwater fish were pike fish, carp, and the less appreciated catfish.
Pictorial evidence of Roman fishing comes from mosaics. At a certain time, the goatfish was considered the epitome of luxury, above all because its scales exhibit a bright red colour when it dies out of water. For this reason, these fish were occasionally allowed to die slowly at the table. There even was a recipe where this would take place in Garo, in the sauce. At the beginning of the Imperial era, however, this custom suddenly came to an end, which is why mullus in the feast of Trimalchio could be shown as a characteristic of the parvenu, who bores his guests with an unfashionable display of dying fish.
In medieval times, seafood was less prestigious than other animal meats, and was often seen as merely an alternative to meat on fast days. Still, seafood was the mainstay of many coastal populations. Kippers made from herring caught in the North Sea could be found in markets as far away as Constantinople. While large quantities of fish were eaten fresh, a large proportion was salted, dried, and, to a lesser extent, smoked. Stockfish - cod that was split down the middle, fixed to a pole, and dried - was very common, though preparation could be time-consuming, and meant beating the dried fish with a mallet before soaking it in water. A wide range of mollusks were eaten by coastal and river-dwelling populations, and freshwater crayfish were seen as a desirable alternative to meat during fish days. Compared to meat, fish was much more expensive for inland populations, especially in Central Europe, and therefore not an option for most.
Modern knowledge of the reproductive cycles of aquatic species has led to the development of hatcheries and improved techniques of fish farming and aquaculture. A better understanding of the hazards of eating raw and undercooked fish and shellfish has led to improved preservation methods and processing.
Types of seafood
The following table is based on the ISSCAAP classification used by the FAO to collect and compile fishery statistics. The production figures have been extracted from the FAO FishStat database, and include both capture from wild fisheries and aquaculture production.Processing
Fish is a highly perishable product: the "fishy" smell of dead fish is due to the breakdown of amino acids into biogenic amines and ammonia.Live food fish are often transported in tanks at high expense for an international market that prefers its seafood killed immediately before it is cooked. Delivery of live fish without water is also being explored. While some seafood restaurants keep live fish in aquaria for display purposes or cultural beliefs, the majority of live fish are kept for dining customers. The live food fish trade in Hong Kong, for example, is estimated to have driven imports of live food fish to more than 15,000 tonnes in 2000. Worldwide sales that year were estimated at US$400 million, according to the World Resources Institute.
If the cool chain has not been adhered to correctly, food products generally decay and become harmful before the validity date printed on the package. As the potential harm for a consumer when eating rotten fish is much larger than for example with dairy products, the U.S. Food and Drug Administration has introduced regulation in the USA requiring the use of a time temperature indicator on certain fresh chilled seafood products.
Because fresh fish is highly perishable, it must be eaten promptly or discarded; it can be kept for only a short time. In many countries, fresh fish are filleted and displayed for sale on a bed of crushed ice or refrigerated. Fresh fish is most commonly found near bodies of water, but the advent of refrigerated train and truck transportation has made fresh fish more widely available inland.
Long term preservation of fish is accomplished in a variety of ways. The oldest and still most widely used techniques are drying and salting. Desiccation is commonly used to preserve fish such as cod. Partial drying and salting are popular for the preservation of fish like herring and mackerel. Fish such as salmon, tuna, and herring are cooked and canned. Most fish are filleted before canning, but some small fish are only decapitated and gutted before canning.
Consumption
Seafood is consumed all over the world; it provides the world's prime source of high-quality protein: 14–16% of the animal protein consumed worldwide, with over one billion people reliant on seafood as their primary source of animal protein. Fish is among the most common food allergens.Since 1960, annual global seafood consumption has more than doubled to over 20 kg per capita. Among the top consumers are Korea, Norway and Portugal.
The UK Food Standards Agency recommends that at least two portions of seafood should be consumed each week, one of which should be oil-rich. There are over 100 different types of seafood available around the coast of the UK.
Oil-rich fish such as mackerel or herring are rich in long-chain omega-3 oils. These oils are found in every cell of the human body, and are required for human biological functions such as brain functionality.
Whitefish such as haddock and cod are very low in fat and calories which, combined with oily fish rich in omega-3 such as mackerel, sardines, fresh tuna, salmon and trout, can help to protect against coronary heart disease, as well as helping to develop strong bones and teeth.
Shellfish are particularly rich in zinc, which is essential for healthy skin and muscles as well as fertility. Casanova reputedly ate 50 oysters a day.