Seafood

Seafoodis any form ofsea liferegarded as food by humans, prominently includingfishandshellfish. Shellfish include various species ofmolluscs(e.g., bivalve molluscs such asclams,oysters, andmussels, andcephalopodssuch as octopus and squid),crustaceans(e.g. shrimp, crabs, and lobster), andechinoderms(e.g. sea cucumbers and sea urchins). Historically,marine mammalssuch ascetaceans(whalesanddolphins) as well assealshave been eaten as food, though that happens to a lesser extent in modern times. Edible sea plants such as someseaweedsandmicroalgaeare widely eaten assea vegetablesaround the world, especially in Asia.
Seafood is an important source of (animal)proteinin manydietsaround the world, especially in coastal areas.Semi-vegetarianswho consume seafood as the only source of meat are said to adhere topescetarianism.
The harvesting ofwild seafoodis usually known asfishingorhunting, while the cultivation and farming of seafood is known asaquacultureandfish farming(in the case of fish). Most of the seafood harvest is consumed by humans, but a significant proportion is used asfish foodto farm other fish or rearfarm animals. Some seafoods (i.e.kelp) are used as food for other plants (afertilizer). In these ways, seafoods are used to produce further food for human consumption. Also, products such asfish oil,spirulinatablets, fish collagen, andchitinare made from seafoods. Some seafood is fed toaquariumfish, or used to feed domestic pets such ascats. A small proportion is used in medicine or is used industrially for nonfood purposes (e.g.leather).
The harvesting, processing, and consuming of seafoods are ancient practices with archaeological evidence dating back well into thePaleolithic.Findings in asea caveatPinnacle PointinSouth AfricaindicateHomo sapiens(modern humans) harvested marine life as early as 165,000 years ago,while theNeanderthals, an extinct human species contemporary with earlyHomo sapiens, appear to have been eating seafood at sites along the Mediterranean coast beginning around the same time.Isotopic analysis of the skeletal remains ofTianyuan man, a 40,000-year-oldanatomically modern humanfrom eastern Asia, has shown that he regularly consumed freshwater fish.Archaeologyfeatures such asshell middens,discarded fish bones, andcave paintingsshow that sea foods were important for survival and consumed in significant quantities. During this period, most people lived ahunter-gathererlifestyle and were, of necessity, constantly on the move. However, early examples of permanent settlements (though not necessarily permanently occupied), such as those atLepenski Vir, were almost always associated with fishing as a major source of food.
The ancientriverNilewas full of fish; fresh and dried fish were a staple food for much of the population.TheEgyptianshad implements and methods for fishing and these are illustrated intombscenes, drawings, andpapyrusdocuments. Some representations hint at fishing being pursued as a pastime.
Fishing scenes are rarely represented inancient Greekculture, a reflection of the low social status of fishing. However,Oppian of Corycus, a Greek author wrote a major treatise on sea fishing, theHalieulicaorHalieutika, 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 (squid,octopus, andshellfish) were common. They were eaten locally but more often transported inland.Sardinesandanchovieswere regular fare for the citizens of Athens. They were sometimes sold fresh, but more frequently salted. Asteleof the late 3rd century BCE from the small Boeotian city ofAkraiphia, onLake Copais, provides us with a list of fish prices. The cheapest wasskaren(probablyparrotfish) whereasAtlantic bluefin tunawas three times as expensive.Common salt water fish wereyellowfin tuna,red mullet,ray,swordfish, orsturgeon, a delicacy that was eaten salted. Lake Copais itself was famous in all of Greece for itseels, celebrated by the hero ofThe Acharnians. Other freshwater fish werepike fish,carp, and the less appreciatedcatfish.
Pictorial evidence ofRomanfishing comes frommosaics.At a certain time, thegoatfishwas 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 placein Garo, in thesauce. At the beginning of the Imperial era, however, this custom suddenly came to an end, which is whymullusin the feast ofTrimalchio(seetheSatyricon) could be shown as a characteristic of theparvenu, who bores his guests with an unfashionable display of dying fish.
Inmedievaltimes, 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.Kippersmade from herring caught in theNorth Seacould be found in markets as far away asConstantinople.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 ofmollusks(includingoysters,musselsandscallops) were eaten by coastal and river-dwelling populations, and freshwatercrayfishwere 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 ofhatcheriesand improved techniques offish farmingandaquaculture. A better understanding of thehazardsof eating raw and undercooked fish and shellfish has led to improved preservation methods and processing.
The following table is based on the ISSCAAP classification (International Standard Statistical Classification of Aquatic Animals and Plants) used by theFAOto 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.
Fish is a highlyperishableproduct: the "fishy" smell of dead fish is due to the breakdown ofamino acidsintobiogenic aminesandammonia.
Livefood fishare often transported in tanks at high expense for aninternational marketthat prefers its seafood killed immediately before it is cooked. Delivery of live fish without water is also being explored.While some seafoodrestaurantskeep live fish inaquariafor display purposes or cultural beliefs, the majority of live fish are kept for dining customers. The live food fish trade inHong Kong, for example, is estimated to have driven imports of live food fish to more than 15,000tonnesin 2000. Worldwide sales that year were estimated at US$400 million, according to the World Resources Institute.
If thecool chainhas not been adhered to correctly, food products generally decay and become harmful before thevalidity dateprinted on the package. As the potential harm for a consumer when eating rotten fish is much larger than for example with dairy products, theU.S. Food and Drug Administration(FDA) has introduced regulation in the USA requiring the use of atime temperature indicatoron 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 arefilletedand displayed for sale on a bed ofcrushed iceorrefrigerated. Fresh fish is most commonly found near bodies of water, but the advent of refrigeratedtrainandtrucktransportationhas made fresh fish more widely available inland.
Long termpreservationof fish is accomplished in a variety of ways. The oldest and still most widely used techniques aredryingandsalting.Desiccation(complete drying) is commonly used to preserve fish such ascod. Partial drying and salting are popular for the preservation of fish likeherringandmackerel. Fish such assalmon,tuna, andherringare cooked andcanned. Most fish are filleted before canning, but some small fish (e.g.sardines) are onlydecapitatedand gutted before canning.
Seafood is consumed all over the world; it provides the world's prime source of high-qualityprotein: 14–16% of the animal protein consumed worldwide; over one billion people rely on seafood as their primary source of animal protein.Fish is among the most commonfood allergens.
Since 1960, annual global seafood consumption has more than doubled to over 20 kg per capita. Among the top consumers are Korea (78.5 kg per head), Norway (66.6 kg) and Portugal (61.5 kg).
The UKFood Standards Agencyrecommends 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 asmackerelorherringare rich in long chainOmega-3oils. 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 inOmega-3such asmackerel,sardines, freshtuna,salmonandtrout, can help to protect againstcoronary heart disease, as well as helping to develop strong bones and teeth.
Shellfishare particularly rich inzinc, which is essential for healthy skin and muscles as well as fertility.Casanovareputedly ate 50oystersa day.
Over 33,000speciesof fish and many more marine invertebrate species have been identified.Bromophenols, which are produced by marine algae, give marine animals an odor and taste that is absent from freshwater fish and invertebrates. Also, a chemical substance called dimethylsulfoniopropionate (DMSP) that is found in red and green algae is transferred into animals in the marine food chain. When broken down, dimethyl sulfide (DMS) is produced, and is often released during food preparation when fresh fish and shellfish are heated. In small quantities it creates a specific smell one associates with the ocean, but in larger quantities gives the impression of rotten seaweed and old fish.Another molecule known asTMAOoccurs in fishes and gives them a distinct smell. It also exists in freshwater species, but becomes more numerous in the cells of an animal the deeper it lives, so fish from the deeper parts of the ocean have a stronger taste than species that live in shallow water.Eggs from seaweed contain sex pheromones called dictyopterenes, which are meant to attract the sperm. These pheromones are also found in edible seaweeds, which contributes to their aroma.
There is broad scientific consensus thatdocosahexaenoic acid (DHA)andeicosapentaenoic acid (EPA)found in seafood are beneficial toneurodevelopmentand cognition, especially at young ages.The United NationsFood and Agriculture Organizationhas described fish as "nature's super food."Seafood consumption is associated with improved neurologic development duringpregnancyand early childhoodand is more tenuously linked to reduced mortality fromcoronary heart disease.
Fish consumption has been associated with a decreased risk ofdementia,lung cancerandstroke.A 2020umbrella reviewconcluded that fish consumption reduces all-cause mortality, cancer, cardiovascular disease, stroke and other outcomes. The review suggested that two to four servings per week is generally safe.However, two other recent umbrella reviews have found no statistically significant associations between fish consumption and cancer risks and have cautioned researchers when it comes to interpreting reported associations between fish consumption and cancer risks because the quality of evidence is very low.
The parts of fish containing essential fats and micronutrients, often cited as primary health benefits of eating seafood, are frequently discarded in thedeveloped world.Micronutrientsincluding calcium, potassium, selenium, zinc, and iodine are found in their highest concentrations in the head, intestines, bones, and scales.
Government recommendations promote moderate consumption of fish. TheUS Food and Drug Administrationrecommends moderate (4 oz for children and 8–12 oz for adults, weekly) consumption of fish as part of a healthy and balanced diet.The UK National Health Servicegives similar advice, recommending at least 2 portions (about 10 oz) of fish weekly.TheChinese National Health Commissionrecommends slightly more, advising 10–20 oz of fish weekly.
There are numerous factors to consider when evaluating health hazards in seafood. These concerns include marine toxins, microbes,foodborne illness,radionuclide contamination, and man-made pollutants.Shellfishare among the more commonfood allergens.Most of these dangers can be mitigated or avoided with accurate knowledge of when and where seafood is caught. However, consumers have limited access to relevant and actionable information in this regard and the seafood industry's systemic problems with mislabelling make decisions about what is safe even more fraught.
Ciguatera fish poisoning(CFP) is an illness resulting from consuming toxins produced bydinoflagellateswhich bioaccumulate in the liver, roe, head, and intestines ofreef fish.It is the most common disease associated with seafood consumption and poses the greatest risk to consumers.The population of plankton that produces these toxins varies significantly over time and location, as seen inred tides.Evaluating the risk of ciguatera in any given fish requires specific knowledge of its origin and life history, information that is often inaccurate or unavailable.While ciguatera is relatively widespread compared to other seafood-related health hazards (up to 50,000 people suffer from ciguatera every year), mortality is very low.
Scombroid food poisoning, is also a seafood illness. It is typically caused by eating fish high in histamine from being stored or processed improperly.
Fishandshellfishhave a natural tendency to concentrate inorganic and organic toxins and pollutants in their bodies, includingmethylmercury, a highly toxic organic compound of mercury, polychlorinated biphenyls (PCBs), and microplastics. Species of fish that are high on thefood chain, such asshark,swordfish,king mackerel,albacore tuna, andtilefishcontain higher concentrations of these bioaccumulates. This is because bioaccumulates are stored in the muscle tissues of fish, and when a predatory fish eats another fish, it assumes the entire body burden of bioaccumulates in the consumed fish. Thus species that are high on thefood chainamass body burdens of bioaccumulates that can be ten times higher than the species they consume. This process is calledbiomagnification.
Man-made disasters can cause localized hazards in seafood which may spread widely via piscine food chains. The first occurrence of widespreadmercury poisoningin humans occurred this way in the 1950s inMinamata,Japan. Wastewater from a nearby chemical factory released methylmercury that accumulated in fish which were consumed by humans. Severe mercury poisoning is now known asMinamata disease.The 2011Fukushima Daiichi Nuclear Power Plant disasterand 1947 – 1991Marshall Islands nuclear bomb testingled to dangerous radionuclide contamination of local sea life which, in the latter case, remained as of 2008.
A widely cited study inJAMAwhich synthesized government andMEDLINEreports, and meta-analyses to evaluate risks from methylmercury, dioxins, and polychlorinated biphenyls to cardiovascular health and links between fish consumption and neurologic outcomes concluded that:
Due to the wide array of options in the seafood marketplace, seafood is far more susceptible to mislabeling than terrestrial food.There are more than 1,700 species of seafood in the United States' consumer marketplace, 80 – 90% of which are imported and less than 1% of which are tested for fraud.However, more recent research into seafood imports and consumption patterns among consumers in the United States suggests that 35%-38% of seafood products are of domestic origin.consumption suggests Estimates of mislabelled seafood in the United States range from 33% in general up to 86% for particular species.
Byzantinesupply chains, frequent bycatch, brand naming, species substitution, and inaccurate ecolabels all contribute to confusion for the consumer.A 2013 study byOceanafound that one third of seafood sampled from the United States was incorrectly labeled.Snapperandtunawere particularly susceptible to mislabelling, and seafood substitution was the most common type of fraud. Another type of mislabelling is short-weighting, where practices such as overglasing or soaking can misleadingly increase the apparent weight of the fish.For supermarket shoppers, many seafood products are unrecognisablefillets. Without sophisticatedDNA testing, there is no foolproof method to identify a fish species without their head, skin, and fins. This creates easy opportunities to substitute cheap products for expensive ones, a form of economic fraud.
Beyond financial concerns, significant health risks arise from hidden pollutants and marine toxins in an already fraught marketplace. Seafood fraud has led to widespreadkeriorrheadue to mislabeled escolar, mercury poisoning from products marketed as safe for pregnant women, and hospitalisation and neurological damage due to mislabeledpufferfish.For example, a 2014 study published inPLOS Onefound that 15% ofMSCcertifiedPatagonian toothfishoriginated from uncertified and mercury polluted fisheries. These fishery-stock substitutions had 100% more mercury than their genuine counterparts, "vastly exceeding" limits in Canada, New Zealand, and Australia.
Research into population trends of various species of seafood is pointing to a global collapse of seafood species by 2048. Such a collapse would occur due to pollution andoverfishing, threatening oceanic ecosystems, according to some researchers.
A major international scientific study released in November 2006 in the journalSciencefound that about one-third of all fishing stocks worldwide have collapsed (with a collapse being defined as a decline to less than 10% of their maximum observed abundance), and that if current trends continue all fish stocks worldwide will collapse within fifty years.In July 2009,Boris WormofDalhousie University, the author of the November 2006 study inScience, co-authored an update on the state of the world's fisheries with one of the original study's critics,Ray Hilbornof theUniversity of Washingtonat Seattle. The new study found that through good fisheries management techniques even depleted fish stocks can be revived and made commercially viable again.An analysis published in August 2020 indicates that seafood could theoretically increase sustainably by 36–74% by 2050 compared to current yields and that whether or not these production potentials are realisedsustainablydependson several factors "such as policy reforms, technological innovation, and the extent of future shifts in demand".
TheFAOState of World Fisheries and Aquaculture 2004 report estimates that in 2003, of the main fish stocks or groups of resources for which assessment information is available, "approximately one-quarter wereoverexploited, depleted or recovering from depletion (16%, 7% and 1% respectively) and needed rebuilding."
TheNational Fisheries Institute, a trade advocacy group representing the United States seafood industry, disagree. They claim that currently observed declines in fish populations are due to natural fluctuations and that enhanced technologies will eventually alleviate whatever impact humanity is having on oceanic life.
For the most partIslamic dietary lawsallow the eating of seafood, though theHanbaliforbid eels, theShafiforbid frogs and crocodiles, and theHanafiforbidbottom feederssuch as shellfish andcarp.TheJewishlaws ofKashrutforbid the eating of shellfish and eels.In the Old Testament, theMosaic Covenantallowed the Israelites to eatFinfish, but shellfish and eels werean abominationand not allowed.
In theNew Testament,Luke's gospelreports Jesus' eating of a fish after hisresurrection,and inJohn 21, also a post-resurrection scene, Jesus tells hisdiscipleswhere they can catch fish, before cooking breakfast for them to eat.
Pescatarianismwas widespread in theearly Christian Church, among both the clergy and laity.In ancient and medieval times, theCatholic Churchforbade the practice of eating meat, eggs and dairy products duringLent.Thomas Aquinasargued that these "afford greater pleasure as food [than fish], and greater nourishment to the human body, so that from their consumption there results in a greater surplus available for seminal matter, which when abundant becomes a great incentive to lust".In the United States, the Catholic practice ofabstaining from meaton Fridays duringLenthas popularised the Fridayfish fry,and parishes often sponsor afish fryduring Lent.In predominantly Roman Catholic areas, restaurants may adjust their menus during Lent by adding seafood items to the menu.