Fish and Shellfish

Omega-3 fatty acids in fish

2012-05-23T18:58:00.001-07:00

There are a lot of benefits relating fish oil to human health, especially from omega 3 fatty acids content in fish oil.

Fish that containing omega-3 fatty acids include salmon, lake trout, tuna and herring. Omega-3 also present in vegetables oils, however these acids are less effective in relation to human health. This makes fish, especially marine fish become one of the richest sources of these vitally important fatty acids.

Researches in animals have found that omega-3 fatty acids found in fish may suppress cancer formation of hinder the progression of cancer.

Omega-3 fatty acids also may reduce the risk of coronary heart disease by reducing blood pressure cholesterol, and triglycerides in the blood.

Unlike saturated fat in dairy products and meats, the fatty acids in fish have been shown in epidemiological studies to be beneficial to health. The strongest evidence for the important of omega-3 fatty acids is reduction in risk of sudden death from cardiac arrest.

Not all fish are equal in omega-3 fatty acid content. Cold water fish contain more omega-3 fatty acids than leaner, warm water fish.

Fish do not make the omega-3 fatty acids they have themselves. Rather they obtain these fatty acids from the algae that the feed on.

Omega-3 fatty acids in fish

Abalone

2012-03-21T19:18:00.000-07:00

Abalone is a shellfish or mollusk, Haliotus spledens, H. rufescens, H. cracherodii, also sometimes called ormer, or sea ear.

The abalone has two features that recommend it to humankind. One is that suitably, tenderized and seasoned, the meat of the abalone is very good eating.

Second, the ‘mother of pearl’ inside surface of shell of the abalone is used in jewelry.

People in many parts of the world harvest abalones. The largest species, the red abalone, is collected along the coast of California, while in southern Australia divers pursue the smaller Roe’s abalone.

Abalones are to be found in many parts of the world, including the coastal zones of the Mediterranean, region, Africa, Australia, New Zealand, the Pacific islands and western North and South America.

Today, China and Taiwan raise more 90% of the world’s farmed abalones in saltwater pens or suspended cages.

It takes three to four years for an abalone to reach market size of four to six while abalone per pound (nine to thirteen per kg).

In the USA there is a traditional market for abalone, which is mainly in California, where there was a flourishing fishery until the early 1970s.

The traditional US market now consists primarily of expensive, white tablecloth restaurants in California.
Abalone

Catfish

2012-03-18T10:17:00.000-07:00

Catfish once viewed disdained fully as the scavenger of fish, has now become a high ranking choice of connoisseurs. It is low in fat, cholesterol and calories perfect for those who are watching what they eat.

Catfish comprise an incredibly large and diverse group of animals much larger, in fact than most people realize. One in four species of all freshwater fishes is a catfish.

Most catfish are found in fresh water, although there are two families that contain saltwater species.

Many of the world’s significant river systems are home to at least one species of catfish, and in most cases these fish rank among the largest fish of the river system.

There is little finesse in angling for any of the catfish. They love in deep holes, often in turbid water, and their diet is unsophisticated, as they use eight sense barbells to locate foods.

Most catfish prefer the sluggish localities of lakes and rivers; some do best in fairly swift waters.

Catfish

Habitats of fish

2012-03-11T03:47:00.000-07:00

Important habitats can be defined as those that support a significant percentage of the population at comparatively high density. The waters and substrate necessary to fish for spawning, breeding, feeding or growth to maturity.

Fishes live in virtually every water habitat found on earth. There are fish in mountain lakes above 4000 meters and fish in the deep ocean, at depth of at least 8300 meters.

The world’s deepest living fish Abyssobrotula galatheae was found in the Puerto Rican Trench at a depth of 8372 meters while Tibetan stoneloach Triplophysa stoliczkai lives at altitudes over 5200 meters in the Himalayas.

In the outflows of hot springs fish can be found living at temperatures of around 42 ° C whereas in the Antarctic, fish can be found resting on chunks of ice surrounded by water that is within a fraction of a degree of freezing solid.

The salinities of the water in which fish are known to live range from the purest water of granitic mountain basins to water over four times saltier than sea water.

Poor fisheries management is one of the biggest threats to marine biodiversity and benthic habitats.

Agricultural practices that alter water flow or increase water runoff from agricultural land would affect the quantity and quality of pond, lake and stream habitats for fish.

Agricultural practices that increase soil erosion greatly aquatic habitats by increasing the siltation and by carrying off nutrients that increase eutrophication.

Habitats of fish

Mackerel fish during ancient times

2011-11-09T18:21:00.000-08:00

Scomberomorus, an ancient name for mackerel fish. The full name is Scomberomorus commerson.

The name mackerel given by the French, German and Dutch was well as British, is derived from the Latin word macula, spot; that is the spotted or streaked fish.

Hence the term ‘mackerel-sky’ is also applied to a well known formation of the clouds.

The mackerel when alive, from the elegance of its shape and the brilliancy of it color, is one of the most beautiful fish.

Historically the mackerel was a prime curing fish because of its oily meat and smaller size.

Archeological evidence from Roman suggests that mackerel were widely consumed; it was from the south coast of Spain, transported in ‘amphorae’, common on the first century AD, less frequent in later century.

It is possible that the ocean going peoples of the Bible were familiar with mackerel. Mackerel remains have been discovered in Stone Age archeological sites, and the ancient Romans prized a certain seasoning, ‘garum’, sometimes made from decomposing mackerel.

In Roman times it was disregarded, the mackerel sold by fishmongers wrapped up in paper fit for no other use.

From it entails, however, was made the famous sauce of antiquity, named in Pliny’s time the ‘garum sociorum’ or allies sauce, in complement to the Spaniards then in alliance with Rome.

Garum used in coking or as condiment at table; greatly demand by gourmets at Rome.
Mackerel fish during ancient times

Tuna distribution

2011-10-09T06:22:00.001-07:00

The major commercial tuna species are albacore, bigeye Atlantic, northern and southern bluefin, skipjack and yellowfin tunas.

The yellow fin tuna is found on the West Coast from Southern California to Southern Chile. Yellow fin tuna are caught by various gears such as purse seines, longlines and baitboats.

Until the development of the purse –seine fishery, most of the catches were made by longlines, which take medium to large-sized fish, as one of the main target species.

Southern bluefin tuna are distributed only in the southern hemisphere and mainly inhabit cold waters around 40 degree S. However, their spawning grounds are in tropical waters.

Bluefin tuna range from Nova Scotia to Brazil on the East Coast and from Southern California to Northern Mexico on the West Coast.

Skipjack is one of the most abundant pelagic tuna species, inhabiting of tropical waters. Skipjack tuna are cosmopolitan and subtropical seas, usually in deep coastal and oceanic waters. The skipjack is found in the Pacific Ocean from Southern California to Central and Southern America.

Albacore is a member of the Scombridae family of tuna and mackerel. It is an excellent light-tackle gamefish. Albacore is best known as Americas highest grade, ‘white meat’ canned tuna.

The albacore ranges from Puget Sound to lower California. The yellow tail is found in Pacific waters from Southern California to the coast of Mexico.

Several other species of tuna found elsewhere, especially in the Eastern Pacific Ocean.
Tuna distribution

Nutrient in seafood

2011-09-06T03:40:00.000-07:00

Seafood is a food source comparable to other animal protein foods in nutrient composition. Because of its nutrients denseness, seafood can help the dietary needs for calcium, essential fats, iodine and protein.

In addition, seafood is an important contributor of selenium to the American diet and is unique among animal protein foods as a rich source or omega-3 fatty acids EPA and DHA.

Salmon and sardines, in particular are good sources of moega-3 essential fatty acids, while halibut is a great source of protein.

It is evident that fish contributes more to people’s diet than just the high quality protein they are known for.

The forms of lipid in fish are triglycerides or triacylglycerols. Triglycerides in pelagic fish contain the long-chain polyunsaturated fatty acid EPA (eicosapentoic acid) and DHA (docosahexanoic acid), which have many health benefits including normal development of the brain and retina in infants and prevention of heart disease in adults.

Research has linked fish consumption with many health benefits, including a lowered risk for arthritis, heart attacks, high blood pressure, prostate cancer in men and strokes.

The WHO/FAO in 2003 recommendation on the consumption of fish is that “regular fish consumption (1-2 servings per week) is protective against coronary heart diseases and ischemic stroke and is recommended. The serving should provide an equivalent of 200-500 mg of EPA and DHA.”
Nutrient in seafood

Fish Diet for Dementia

2011-06-28T09:57:00.001-07:00

Dementia is descriptive term for a collection of symptoms that can be caused by a number of disorders that affect the brain. People with dementia have significantly impaired intellectual functioning that interferes with normal activities and relationships. They also lose their ability to solve problems and maintain emotional control and they may experiences personality changes and behavioral problems, such as agitation, delusions and hallucinations.

Small brain lesions, detectable only on scans, have been linked to the loss of thinking skills and dementia. Might eating fish, which is thought to be good for the brain, affect the development of these lesions, called silent brain infarct?

There was a study involved 2,313 generally healthy older people, most in their mid-70s, who had brains scans at the start of the study and again five years later.

Lesions were detected in about 23% of the participants. Those who ate broiled or baked tuna or other fish high in omega 3 fatty acids three or more times a week were 26% less likely to have brain lesions than were those who ate such fish once a moth or less. Eating fish once a week reduced the risk by 13%. No benefit was found for eating fried fish.

Who may be affected? Older people. Although head injury, stroke or brain tumor can destroy brain cells and lead to dementia, the condition becomes more prevalent simply with age. In another study, the French researchers found the links between eating fish which has high levels of polyunsaturated fatty acids and a reduced risk of dementia, including Alzheimer’s disease when there asked elderly people about their eating habits. This research involved 1,670 people age 68 or over living in south west France.

It was found that those who ate fish or seafood at least once a week had a significantly lower risk of developing dementia over the seven years of the study.
Fish Diet for Dementia

Ancient Anchovy

2011-06-15T20:21:00.000-07:00

The anchovy was a well known to the Greeks and Romans, by whom the liquor prepared from it, called Garum, was in great estimation.

Anchovy species was to the ancient world what the herring has became to the modern, compensating in some degree for its inferiority.

The ancient anchovy was under a variety of names, some definite and specific, others more general and vague.

The word anchovy was introduced to English in 1596 by Shakespeare, who made the tiny fish a favorite of his most corpulent character, Falstaff.

The word anchovy comes from Basque, a language spoken in parts of Spain and France but related to no other language in the world.

The Basque source of anchovy – anchoa, meaning dry, was probably bestowed upon the fish because they are usually dried and salted before being sold: such preparations are necessary because small fish go bad more quickly than large fish.

In ancient times anchovies had the capability of being stored for long periods though the process of drying and grinding.

In ancient Greece, anchovies have been the most praised salted fish in the Mediterranean, and since the Middle Ages those of Collioure have been regarded as the east salted anchovies in the world.

More than 130 species of anchovies are currently recognized. The family name for anchovies has been widely cited as Engraulididae.

The anchovies primarily found in coastal marine environments of the tropics and temperate regions. Some species enter freshwater environment sporadically and other species appeared to be restricted to freshwater.
Ancient Anchovy

The Mackerel family

2011-04-19T02:49:00.000-07:00

One of the major important segment of seafood industry in the United States is that which processes fishes of the mackerel family including the various tuna, the Atlantic mackerel, the jack mackerel and the Spanish mackerel.

Mackerel are no less plentiful in Baltic, North Sea, German Ocean, and all along the Scandinavian coasts, though its appearance is always erratic, since it is migratory in its habits.

Tuna are torpedo-shaped fish torpedo to a pointed nose and a slender caudal peduncle (the portion near the tail).

The more important species tuna include the bluefin, the yellowfin, the skipjack, and the albacore.

All mackerel are slim, cylindrical fish with razor sharp teeth that feed on smaller fish and squid.

Mackerel are much smaller than tuna, but they are similar shaped.

They are prized for their stay meat and their fighting ability and are important commercial and game fish.

Mackerel is one of the prettiest fish there is and one of the tastiest, cheapest and still most plentiful.

Apart from that it is small in size, the color being a steel blue, striated with undulating bands of black, while the belly is of a lustrous white, reflecting a bright silvery sheen when first take from the water.

In general, mackerel is very high in calories and fat and high in cholesterol, potassium, phosphorus and vitamin D and B12.
The Mackerel family

Seafood can cause Gout

2011-01-11T21:34:00.000-08:00

While seafood may be healthful for many, some choices can be quite harmful to individuals with gout.

There is small but significant association between incidence of gout and increased consumption of seafood.

What is gout? Gout is considered a form of arthritis that may benefit from anti-inflammatory diet that restricts saturated fat and sugar and includes omega-3 fatty acids.

People with gout suffer from joint pain caused by a buildup of uric acid.

Uric acid is the end product of the degradation of chemical called purines. The diet most often recommended for gout restricts purines.

Purine is one of uric acid component.

Most of our own purines are recycled for re-use by our cells. The problem is that our food contributes to purines, which are broken down immediately in the gut membranes to create uric acid before transported in the blood to the kidney.

If the level of uric acid raised in the blood due to purine rich food like seafood is taken rapidly where no more can be dissolved, crystal will form.

Crystal will be deposited in joints and soft tissue, where they cause local mechanical pressure and acute or chronic inflammation.

In the early stages, gout is characterized by episodic attacks of joint inflammation, which are usually monoarticular (affecting one joint) and begin abruptly with intense pain, swelling, warmth and redness of the affected joint.

Purines are most concentrated in seafood and shellfish. Seafood ahs some of the highest purine content, especially sardine, anchovies, salmon and herring.
Seafood can cause Gout

Abalone

2010-08-17T03:47:00.001-07:00

Abalone
The meat from a large mollusc that lives off the coasts off of California. There are eight species that inhabit the Pacific waters: red (the largest, and the most import commercial abalone), green, black, flat (small in sole and most prize), white (found in depths up to 150 feet and commercial included with the pink abalone) and the three least common species - threaded, pink and pinto.

All the varieties offer meat that is extremely sweet and tasty, but it is usually tough and rubbery and requires tenderizing with mallet prior to cooking.

Today, the abalone industry is highly regulated, as the mollusc continue to be favorite food or sea otters and are scarce.

Since the earliest poetry, dating back to anthology of Japanese verse Man'yoshu, their unique iridescent shells have been likened to unrequited love by drawing symbolic parallel between one sided love and the abalone’s single shell.

For this reason, in the folklore of cuisine, abalone cannot be served at wedding banquets, although other bivalve shellfish are often eaten.

Folklore also says that abalone is helpful for arthritis and other joints disorders, muscle problems, the heart and digestion.

Abalones are known to have existed as long as the Upper Cretaceous age. They now occur in the Mediterranean, and even on the coats of England, but it is only in the Pacific that they attain great size, most being found off California, Japan, New Zealand and Australia.
Abalone

Fish Farming of the Sea

2010-08-08T09:36:00.000-07:00

Fish Farming of the Sea
The global appetite for fish has doubles over the last thirty years. But because of depletion of the world stock, virtually all the growth in the catch today comes not from the ocean but from fish raised on farms, or aquaculture.

As the demand for fish skyrockets, producers are adapting more intensive, industrial style methods, which can cause the same sorts of problems as those on land.

Farmed salmon, for example, spend the 2 – 3 years of their lives crammed into pens, where there are fed high protein fish meal. This practice of giving farmed fish the ground up bits of other marine species results in a net loss to world fish protection: according to a study, for ten types of fish commonly farmed on average of 1.9 kilograms of wild fish is required for every kilogram of farmed fish.

There is a proposing the next phase of fish farming open ocean aquaculture, or the constriction of penned farms for large carnivores fish fattened with fish meal, located more than 300 kilometers offshore.

As with livestock, farmed fish often contain a range of unexpected ingredients. They require massive doses of antibiotics and pesticides to prevent diseases that result from overcrowding , including sea lice, a parasite that can spread quickly in crowded pens.
Fish Farming of the Sea

Crustaceans

2010-07-10T08:32:00.000-07:00

Crustaceans
Crustaceans are the most valuable group of marine organism. They form about 4% of the total world catch. Almost all species in this group are considered on the world market as high value commodities.

The most important group are shrimps or prawns. The two names refer to the same group which on is used depends upon local preferences.

Shrimp are distributed all over the world. From the commercial point of view, they can divided into cold, warm and freshwater species.

Coldwater species, e.g. Pandalus borealis and Crangon crangon, grow slowly and are small in size, compared to warmwater species, mainly of the Penaeus family which grow quickly, reaching a large size.

Freshwater species, mainly Macrobranchium rosenbergii, inhabit tropical lakes and rivers, growing very fats and reaching a very large size up to 0.3 kg.

For that reason shrimps of Penaeus and Macrobranchium families are now successfully cultured.

Tropical marines species are the most important part of world trade in crustaceans with main markets in the US and Japan.

Cold water species are preferred in Europe.

Due to high commercial value, processing and trading of shrimp are highly specialized. Shrimp are sold alive, fresh, frozen, canned, dried and in a number of different forms, e.g. whole, headless, shell-on, peeled, peeled and deveined, etc.

There is precise grading by size systems, i.e. numbers per 1 kg or 1 lb, different in the US and Japan.

Another important and valuable group of Crustacea is the crab. Caught usually by traps they form a base for the canning industry, particularly in the US, the USSR and Japan.

Crabs are also sold fresh an frozen. Of all crabs, Pacific snow crabs Chionoecetes spp. and king crabs Paralithodes spp, are the most important species.

Lobsters are considered a delicacy all over the world and are this highly priced. Due to their edible, lobsters are sold unprocessed, commonly alive, but as a majority fresh or frozen. There are many different species of lobsters of which spine lobsters Panulirus spp, rock lobsters Jasus spp., American lobster Homarus americanus, and European lobsters H. gammarus are the most important ones.

Coldwater lobsters of Homarus spp, differ significantly in shape from the first ones inhabiting warm waters. The Homarus spp. have strong claws and can reach the size of a few kilograms.

There re also vast quantities of small pelagic crustacea Euphausidacea of which Antarctic krill Euphausia superba form the largest concentrations, thus enabling efficient catches.
Crustaceans

Seafood Consumption Among Asian American Populations

2010-05-26T23:44:00.000-07:00

Seafood Consumption Among Asian American Populations
Among Asian American and Pacific Island members of the population in the contiguous United States seafood consumption is an important aspect of cultural behavior.

Self-harvesting and consuming seafood are seen as healthy activities that echo a culturally familiar lifestyle, but may also be an economic necessity.

Asian American and Pacific Island groups consume greater amounts, different types and different parts of seafood than the general population.

A large population of Laotian immigrants who settled in Wisconsin have been studied to determine how their fishing and seafood consumption habits differ from those of the general US population.

The experts in 1994 found that individual in Laotian immigrants households in Green Bay, Wisconsin, consumed an average of 30 fish meals per year compared to 18 fish meals per consumed buy Wisconsin anglers in the general population.

About one third of the fish caught were reported to come from lakes where fishing advisories warned against eating locally caught fish, suggesting that this group is at greater risk from exposure to contaminant in fish than the general population.

Some members of the Asian American population have undergone acculturation resulting in food choices that are more similar to those of the general US population than populations groups from their country of origin.

Research findings show that dietary changes among succeeding generation of Japanese American females and suggest that acculturation-related changes may contribute to decreased intake of many tradition foods, including fish.
Seafood Consumption Among Asian American Populations

Protein Quality in Seafood

2010-04-24T07:13:00.000-07:00

Protein Quality in Seafood
Protein quality is determined by the amount essential amino acids present.

Mostly, but not all, animal protein is a complete protein (all essential amino acids present at required levels).

In contrast, most protein from plant sources lack adequate amounts of one or more essential amino acid and are “incomplete.”

Combining small amounts of high quality animal protein with plant proteins improves the quality of the latter.

The quality of seafood protein is high, comparable with meat and poultry. Amino acid values compare well with the FAO reference pattern.

It high quality protein makes seafood a attractive accompaniment to vegetable protein sources such as legumes and cereal grains where a small amount of seafood will greatly enhance the value of the vegetable protein.

Nutritive quality and protein efficiency ration (PER) ranks fish protein above casein, the major protein in milk.

Protein form seafood us easily digested, with most species showing a protein digestibility greater than 90%.

The protein of minced flesh of underutilized species and by catch is generally comparable in percentage of protein, amino acid profile, chemical score, and protein efficiency ratio to fillet protein.

Surimi and products made from it supply essentially the same nutrients as the minced flesh from which it is made, with several exceptions.

Less niacin and potassium is present, and added salt increases the sodium content.
Protein Quality in Seafood

Temperature of the seas

2010-04-07T17:57:00.000-07:00

Temperature of the seas
The seas and oceans have a very large heat capacity; hence, they’re not very susceptible to rapid temperature changes.

Usually the surface temperatures of sea waters range from about 28 to -25 degree C. Areas of exceptionally high temperature such as the Persian Gulf 36 degree C, are rather rare.

The temperature of the sea waters depends on the latitude, water currents the season and the depth.

Only in the surface layers influenced by the weather conditions, do the changes temperature take place within a few hours,.

In deeper waters, seasonal cycles of temperature are noticeable while at great no fluctuations in temperature take place.

The influence of temperature in the biological life in the seas is both direct and indirect.

The temperature affects the solubility of oxygen in the sea water and the intensity of the metabolism of the organisms.

Many marine organisms are very well adapted to fluctuating environmental conditions, while other can live only within a very limited range of temperatures.

The stenothermic drifting plankton organisms perish instantaneously on being brought with the sea currents into areas of very different temperature.

Such zones of convergence of warm and cold waters usually abound in nutrient, originating from mineralization of dead animals or plants.

The water temperature is one of the most essential factors affecting the distribution of fish in the seas.

Favorable thermal conditions are especially important for the development of the fertilized eggs. The density of the sea water depends on the salinity and temperature, influencing in turn the vertical distribution of the eggs.

Cold waters are generally more fertile than warm seas and are inhabited by a comparatively small number of species, reaching vast populations in years of favorable hatching and feeding conditions.

On the other hand, warm water seas are generally the habitat of many species competing for food, These species usually do not form large populations.
Temperature of the seas

Major Types of Seafood

2010-03-09T06:42:00.000-08:00

Major Types of Seafood
There are several ways to consider the major types of seafood consumed.

Over this decade, shrimp and tuna remained the most frequently consumed seafood; the top ten seafood types were consistent, except that tilapia replaced scallops.

The most regional difference in seafood consumption were attributable to freshwater and shellfish.

Generally, consumption of freshwater species was greater in inland compared to coastal regions, but the species consumed varied between northern and southern coastal areas, e.g. consumption of clams was greater in New England whereas consumption of clam was greater in South Atlantic and Pacific states.

Another way of considering the top seafood is to compete the percentage of the population having eaten different types of seafood.

Shrimp and tuna are the types consumed by the largest percentage of respondents and crab salmon, clams, catfish, scallops and cod are included among the top choices.

“Breaded fish” is not identified by type, and could represent some double counting with other types, but is of interest for its relatively high use and caloric density.
Major Types of Seafood

Protein in Seafood

2010-02-23T08:13:00.001-08:00

Protein in Seafood
The protein content of most raw finfin flesh is 18-22%, while cooked portions may have as much as 35% protein.

However, some species of sole are reported to be as low as 15% protein.

Mackerel have a high fat to contain 16-18% protein, varying by season.

Crustacean (crabs and shrimp) flesh is slightly higher in protein, while molluscs, especially oysters, will be longer, averaging 8-9% protein content.

Shark (dogfish or greyfish) has been shown to average only 12.6% protein.

Protein quality is determined by the amounts of essential amino acids present. Most, but not all, animal protein is a “complete” protein.

In contrast , most proteins from plant sources lack adequate amounts of one or more essential amino acids and are “incomplete”.

Combining small amounts of high quality animal protein with plant proteins improves the quality of the latter.

The quality of seafood protein is high, comparable with meat and poultry.
Protein in Seafood

The Species of Hakes

2010-02-06T05:06:00.000-08:00

The Species of Hakes
There are several species of hakes, the most important of which is the silver hakes or whiting.

The whiting is most abundant in waters off Nova Scotia. It is caught and handled in much the same manner as are cod. Some whiting are headed, guttered, washed and frozen without further cutting, for utilization as food.

With all members of the cod family, small fish, species not especially prized as food (red hake, etc) and fish frames (the portion remaining after the fillet has been cut away) may be passed through mechanical meat/bone separators (machines that separate the flesh portion from bones and skin).

This provide significant yield of edible, ground fish flesh (resembling hamburger in texture) that may be used to produce frozen fish blocks to be further processed into fish portions, fish sticks and so on.

Handled in conventional fashions, such products are not stable in frozen storage since the fat oxidize and becomes rancid, and the issues get tough at a faster rate than that of the corresponding fillets held under the same conditions.

The faster oxidation of fats probably due to a greater exposure to oxygen because of the great increase in surface area.

The increased rate of toughening may be due to a wider distribution of the enzyme that decomposes trimethylamine to form dimethyl amine and formaldehyde.

The latter composes known to denature proteins.

The spoilage reactions may be slowed considerably by storing at lower temperature, e.g. -20 degree F or -28.9 degree C.

Rancidity can be prevented altogether by protecting the product with a wrapper or gas impermeable plastic film, for example, polyester, PVC, Nylon 11, aluminum laminate.
The Species of Hakes

Mollusks

2010-01-16T04:28:00.000-08:00

Mollusks
There are over 130,000 species of mollusks, varying in size a few million to over 20 m. However, only rather small group of this vast phyla are commercially important.

The edible mollusks can be divided into three main groups: univalves having a single shell, bivalves which have two shells, and cephalopods.

The first group consists of snail, winkles, whelks and abalones, the second of oysters, mussels and clams and the third of squid, cuttlefish an octopus.

Mollusks form about 7% of the total world catch and play an important role in international trade.

The majority of uni- or bivalves are commonly consumed fresh, sold on the market with the shell on. However, freezing as well as canning of shelled meat, plays an increasingly important role.

Cephalopods exist practically in all waters, exhibiting considerable variety of form and eating characteristics. Texture is of particular concern.

Cephalopods are marketed in many forms mainly as fresh, canned, dried, slated, and smoked. The most important of all cephalopods are squids. Most commercially exploited squids belong to two main families: Ommastrephidae and Loliginidae.

The most important single species are Todarodes pacificus and Ommastrephes bartrami.
Mollusks

Seafood Consumption

2009-12-17T19:49:00.001-08:00

Seafood Consumption
Seafood contributes a variety of nutrients to the American diet, including protein andimpriatnt micronutrients, and its eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) content distinguished it as providing a unique benefit.

EPA and DHA are abundant in some seafood types and the conversion from alpha-linolenic acid (ALA) is inefficient in humans.

Seafood is not a primary source for ALA. EPA and DHA are believed to be important in reducing the risk of cardiovascular disease, lengthening gestation and possibly promoting fetal and infant neurological development.

For these reasons, several group have recommended inclusion of seafood, particularly those choices high in EPA/DHA, in the American diet.
Seafood Consumption

Moisture of Fresh Fish

2009-11-02T19:09:00.000-08:00

Moisture of Fresh Fish
Water is the principal component (up to 80%) of the edible portions of seafood.

Usually the oil and water content together total about 80%, The method of storage as well as further processing, such as freezing, determines the final moisture content of the fish flesh.

Considerable moisture, as well as soluble nutrients, may be lost in thaw drip. Water retention is highest in fresh fish.

Finfish moisture contents generally show an inverse relationship to the lipid content.

Raw shellfish moisture contents fall in the same range as finfish, but the average is slightly higher, 80.1%.

About one fourth of the moisture can be lost during cooking, which results in concentration of other components.
Moisture of Fresh Fish

Pollock

2009-10-14T18:05:00.000-07:00

Pollock
Pollock are found on both sides of the Atlantic from Norway to the Chesapeake bay but are most plentiful in waters off Nova Scotia, Cape Cod (Georges Bank), and in the Gulf of Maine.

Pollock eat shrimp, crabs and other crustaceans and small fish. They do not eat bivalve mollusks.

Pollock are caught in waters at levels between the surface and a depth of 450 ft (137 m). They are caught handled aboard the boat, and processed in much the same manner as that described for cod. Small quantities of pollock are salted and dried.

Pollock support the largest fishery in US waters and comprise to 80% of the annual catch in the eastern Bering Sea and around the Aleutian Islands.
Pollock

Utilization of Catch

2009-09-14T21:10:00.000-07:00

Utilization of Catch
The need for better management and utilization of the world resources which are available only at a growing cost for the necessary equipment and energy has encountered more careful and sophisticated handling and preservation of the catch on board to keep the fish longer in the state of prime freshness, to extend the shelf life and to reduce losses due to spoilage.

In many specialized fisheries, it also proved justifiable to utilize the by products, which until recently had been discarded overboard.

On the other hand, very high prizes, paid for top quality fish of prime freshness, have made it possible to apply individual treatment of such resources and air freight the catch to distant quality markets.

The depletion of many species, traditionally used for making worldwide or locally popular fish products, has encouraged efforts to produce the traditional commodities from other, less suitable but abundant raw materials by properly modifying the technology.

Some resources, which were in the past regarded as raw material for fodder meal, are now being used for human consumption.

In the wake of the breakthrough made by the American invention of the fish fingers in the 1950s, many fish species of rather low traditional commercial value have made a name as raw material for various products composed of minced fish flesh.

Furthermore, the fish minces in form of bland preparations, known as surimi, have been used not only in the seafood industry, but are also being regarded as suitable for blending with other material in non fish foods.

Although much effort was spent in research on dry fish protein concentrates, the commercial application of results has not met high expectations.
Utilization of Catch