Fish and Shellfish

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

Risks Associated With Seafood

2009-08-27T11:30:00.000-07:00

Risks Associated With Seafood
The safety of seafood in the US has increased in recent decades, although there are still a number of chemical and microbial hazards that are present in seafood.

Whether a contaminant poses a health risk to consumers depends on the amount present in the food and the potential outcome from exposure.

Consumers are exposed to a complex mixture of dietary and non-dietary contaminants.

However, most studies of the risks associated with seafood focus on one contaminant at a time rather than a mixture.

The extent to which such co-exposure might affect the toxicity of seafood-borne contaminants is largely unknown.

Similarly, few data are available on the extent to which beneficial components of seafood, such as selenium, might mitigate the risks associate with seafood-borne contaminants.

The evidence reviewed indicates that the levels of different contaminants in seafood depend on several factors such as species, size, location, age and feed source.

Levels of some contaminants in seafood vary substantially due to their geographic localization; areas of highest variation tend to be mostly fresh-water.

Consumption of aquatic foods is the major route of human exposure to methyl-mercury. The seafood choices a consumer makes and the frequency with which different species are consumed are thus important determinants of methyl-mercury intake.

Exposure to MeHg among US consumers in general is a concern because there is uncertainty about the potential for subtle adverse health outcomes.

Persistent organic pollutant (POPs), including dioxins and PCBs, can be found in the fatty tissue of all animal derived foods, including seafood.

The greatest concern is for population groups exposed to POPs is seafood obtained through cultural subsistence, or recreational fishing, because of reliance on fish from location that may pose a greater risk.

In contrast to heavy metal contaminants and POPs, the number of reported illness from seafood-borne microbial contaminants has remained steady over the past several decades.

Exposure to vibrio ad norovirus infection is still, a concern, however, because they continue to be associated with consumption of raw molluscan shellfish.

Strategies for minimizing the risk of seafood-borne illness are, to some extent, hazard-specific, but overall include avoiding types of seafood identified as being more likely to contain certain contaminants, and following general food safety guidelines, which include proper cooking.
Risks Associated With Seafood

The Resources

2009-08-07T20:07:00.000-07:00

The Resources
Around five sixths of the surface of our planet is covered with water. This vast area represents a giant volume in which around 20,000 species live and multiply.

Since antiquity fishing and seafood consumption has played an important role in coastal regions.

In contrast to other maritime deep water resources seafood undergoes a continuous biological renewal and recycling. Only human interference by overfishing pollution of the environment can put an end to this eternal biological circle.

Under the pressure of big demand many valuable species of marine fish and invertebrates are now being produced under controlled conditions in aquaculture.

Fish are highly efficient in converting food into animal proteins. For every 1.5 kg of feed they gain 1 kg of body weight. This equal poultry converting feed protein into body protein.

Generally this conversation rate is higher than in slaughter animals.

The labor productivity is high since a well managed catfish farm can yield about 5 ton of fish per man year of labor from 1 acre of earthen ponds.

This compares favorably with industrial beef farming.

The steady increase of industrial fish farming shows in some countries great potentials. Catfish, carp, trout, tuna and salmon are harvested in aquacultures. Fish species with fer bones, white meat and a mild flavor are attractive to the consumer.

It may be assured that industrial fish farming will gain further prioress and development though organized research including genetic engineering.
The Resources

The Primary Findings the Health Benefits of Seafood

2009-07-06T19:26:00.000-07:00

Health Benefits of Seafood
Seafood is a nutrient rich food that makes a positive contribution to a healthful diet. It is a good source of protein, and relative to other protein foods, e.g., meat, poultry, and eggs, is generally lower in saturated fatty acids and higher in the omega-3 fatty acids EPA and DHA as well as selenium.

The evidence to support benefits to pregnancy outcome in females who consumes seafood or fish-oil supplements as part of their diet during pregnancy is derived largely from observational studies.

The studies have also shown an association between increased duration of gestation and intake of seafood or fish-oil supplements. Evidence that the infants and children of mothers who consume seafood or EPA/DHA supplements during pregnancy and/or lactation may have improved developmental outcomes is also supported largely by observational studies.

Observational evidence suggests that increased seafood consumption is associated with a decreased rick of cardiovascular death and cardiovascular events in the general population.

Evidence is inconsistent for protection against further cardiovascular events in individuals with a history of myocardial infarction from consumption of EPA/DHA-containing seafood or fish-oil supplements. The protection evidenced by population (observational) studies has not been consistently observed in randomized clinical trials.

Evidence for a benefit associated with seafood consumption or fish-oil supplements on blood pressure, stroke, cancer, asthma, type II diabetes, or Alzheimer’s disease is inconclusive. Whereas observational studies have suggested a protective role of EPA/DHA for each of these diseases, supportive evidence form randomized clinical trials is either nonexistent or inconclusive.
The Primary Findings the Health Benefits of Seafood

Moisture in fish

2009-06-10T18:49:00.000-07:00

Moisture in fish
Water is the principle 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.

The average percentage of moisture in raw edible flesh, summarized from various sources, is 77.2 with a range of 64.3 – 82.8%.

Raw shellfish moisture contents fall in the same range as finfish, but 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 in fish

Benefits Associated with Nutrients from Seafood

2009-05-05T07:43:00.000-07:00

Benefits Associated with Nutrients from Seafood
The high nutritional quality of seafood makes it an important component of a healthy diet.

While protein is an important macronutrient in the diet, most American already consumes enough and do not need to increase their intake.

Fats and oil are also part of a healthy diet, but the type and amount of fat can be important - for example, with regard to cardiovascular disease.

Many Americans consume greater than recommended amounts of saturated fat as well as cholesterol from high-fat protein foods such as beef and pork.

Many seafood selections are lower in total and saturated fats and cholesterol than some more frequently selected anima protein foods such as fatty cuts of beef, pork and poultry and are equivalent in amount of fat to some leaner cuts of meat.

Since it is lower in saturated fats however by substituting seafood more often for other animal foods, consumers can decrease their overall intake of both total and saturated fats while retaining the nutritional quality of their protein food choices.

Seafood is also a primary source of EPA and DHA in the American diet.

The contribution of the nutrients to improving health and reducing risk for certain chronic disease in adult has not been completely elucidated.

There is evidence however, to suggest there are benefits to the developing infants such as increasing length of gestation, improved visual acuity and improve cognitive development.

In addition, there is evidence to support an overall benefit to the general population for reduced risk of heart disease among those who eat seafood compared to those who do not, and there may be benefits from consuming EPA and DHA for adults at risk for coronary heart disease.
Benefits Associated with Nutrients from Seafood

The Past of Fish as a Major Food Source

2009-04-09T18:10:00.000-07:00

The Past of Fish as a Major Food Source
Although the utilization of fish as a major food source has been recorded since historic times, the real development has been since the turn of the century, and more particularly over the past 50 or so years.

This was made possible by the modernization of vessels and fishing gear, the scientific application of canning and freezing techniques, the application of sanitation standards, improved packaging and packaging equipment and the modern logistics system involving transportation, storage and marketing.

From ancient times until the present century, seafood was preserved by removing water (dehydration) and/or adding salt to reduce microbiological activity though reducing water activity.

Beginning at the turn of the century and growing until past decade was the preservation by canning, or hermetically sealing and heat processing.

Since the 1940s, the development of modern refrigeration and cold storage holding has stimulated a continuing growth in the use of frozen products.

The availability of both simple and sophisticated preservation techniques, as well as the economic condition of different countries, has resulted in two major distinctions between the fishery products being produced and consumed worldwide.

These are the high cost, seasonal fisheries (e.g., salmon, halibut, crab, shrimp, tuna, etc.) and the low cost, year round or nearly year round fisheries (e.g., anchovy, certain bottom fish, pollock, carp, etc).

The seasonal species are being consumed in countries that can afford the high cost item resulting from the many logistic problems associated with this type of fishery.

Furthermore, the consumer in this market demands the high quality only achieved by more costly processing and distribution.

Many of the lower-cost products are being consumed in the developing countries, while their high priced products are exported for hard currency.

If a country has enough low cost fish, this practice actually affects only the style of eating rather than the nutritional status of a population.

In fact, as will be seen in discussing processing and preparation of fishery products, sometimes low cost fish can be a better source of nutrients.
The Past of Fish as a Major Food Source

Haddock

2009-03-02T23:59:00.000-08:00

Haddock
The haddock is the second most important member of the cod family.

Haddock are found on both sides of the Atlantic from Norway to New Jersey but are most plentiful in waters off Nova Scotia and Cape Cod.

The mature fish feed on crustaceans (crabs, shrimp, etc), molluscs (clams, etc.), and on small fish.

In recent years, the stocks of haddock have been greatly depleted due to overfishing.

Haddock are usually caught in areas where the depth of water is 150 – 360 ft (45.7 – 109.7 m).

They are caught, handled aboard the boat, and processed to produce fillets, fish blocks, and fish sticks in the same manner as that described for cod.

Haddock are not salted and dried. Some haddock are lightly salted and lightly smoked, without heat, to produce a product called “finnan haddie”.
Haddock

World of Fisheries

2009-02-04T22:06:00.000-08:00

World of Fisheries
With an increasing percentage of fish going to the frozen and fresh markets, and the increasing requirement for high quality waste (secondary raw materials for by products), the attitude for the entire fishing industry is changing.

Although many problems related to seafood are much more complicated than some for those faced by agriculture, the fishing industry has been grossly negligent in its concern about quality control of raw materials.

The new industry means technology from harvest through handling, processing, holding and distribution to the final market. This sequence must be started by the fisherman.

The number of experts differing on the role that food from the main and freshwater bodies of the world should play in mankind futures staggers the imagination.

The complex physical and biological environments, the difference in food requirements between many developed and developing nations, and the political relationships between nations (particularly those on continental and island sea coats) greatly complicate predications of these food resources and the ability to chart a course of action.

The highly nutritious protein foods form the sea and inland fresh waters do have an important place in feeding people. This impact can be increased tremendously through both harvesting and aquaculture operations.

Like all modern developments based on technology, the solution involves major financial investments, enlightened management and wise application of the technology.
World of Fisheries

Processing of Cod

2009-01-15T16:49:00.000-08:00

Processing of Cod
At the processing pant, the cod are washed and filleted, skinless.

Fillets that are to be frozen for the retail trade are packed in 1 lb (454 kg) waxed carton with or without being first wrapped in moisture vapor-proof plastic.

The fillets may have been passed through a weak brine (10 – 45% saturated salt solution) prior to packaging. For purposes of freezing, retail sized cartons of fillets may be placed on trays, the trays placed on racks, and the racks wheeled on top a blast freezer where very cold air is blown over the product, or the cartons may be plate frozen by being placed in trays in contact with refrigerated plates at -28 degree F (- 33.3 degree C).

Some cod fillets are frozen, usually in a plate freezer, and then cut into fish sticks or fish portions that are then breaded in a batter of flour, dried milk solids, egg solids, spices, and flavoring.

The product is then packaged in retail-sized units and held frozen until sold to customers.

Salted cod was once a major export commodity of the United States, only very little cod is now salted in this country. To produce salted cod, the fish are beheaded and split longitudinally; the backbone and the abdominal cavity lining are remove, washed and layer salted in closed casks (brine salting), in open tubs, or simply in open piles on a low platform (dry salting).

Most of the salted cod is produced by dry salting that is done to produce either a lightly salted product or a heavily salted product. The lightly salted product requires many days to complete, has a relatively low salt content (less than 10%), has better organoleptic properties than the heavily salted once, but it is not shelf stable, the heavily salted product requires week to complete, has a high salt content (about 30%) and is shelf stable.
Processing of Cod

The Soft-Clam Shell

2008-12-30T07:26:00.000-08:00

The Soft-Clam Shell
The soft-clam shell is found in the Western Atlantic as far as the Artic regions and as far south as Virginia, being most plentiful off the coasts of New England, New Jersey and Virginia.

In New England, soft-shell clams are harvested when the tide is low by digging into the mud with the short handled clam hoe and removing them by hand.

In the Chesapeake Bay area clams are harvested from boats using water jet dredges and escalator. They are placed in bags or basket and brought to the processing plant, where they are washed with sea water and sorted according to the size.

Specimen 3 in. (7.6 cm) in length or less are usually cooked by steaming. The larger size clams are removed from the shell by hand and placed in metal containers, after which the containers are refrigerated by being surrounding with crushed ice.

In this form, they are shipped to restaurants to be served as a breaded deep fat fried product. Soft-shell clams may be removed from restricted areas and depurated.
The Soft-Clam Shell

Methods That Keep Seafood Alive

2008-12-17T15:55:00.000-08:00

Methods That Keep Seafood Alive
The trapping techniques certainly provide the best opportunity for the fisherman to land and supply the freshest highest quality product. When an animal becomes trapped in a closed area, it remains alive and untouched until it is removed. Therefore, as long as the traps are judiciously operated and emptied on a reasonably cycle the seafood is removed and slaughtered just prior to sale or use.

An excellent example of the use of traps (pots) is the crab industry. In fact, most crabs must be butchered while alive in order to ensure that the meat is well bled. Otherwise there will be a “blueing” of the meat. This is due to the blood chemistry of a crustacean.

While most animals have a heme (iron) complex in their blood, crustacean have a copper complex. When the blood is not removed prior to processing, the copper oxidizes, giving the giving the white crabmeat an unsightly blue color. Although the basic nutritional value is not impaired, the sensory-oriented consumer does not like and will not purchase blue colored crab.

The ultimate in retaining live fish and shellfish in containers or penned areas is found in fish farming or aquaculture. In this case, the raw materials are raised throughout their life cycle in captivity in a normal farming type operation.
Methods That Keep Seafood Alive

Processing of Hard Shell Clam

2008-12-08T08:00:00.000-08:00

Processing of Hard Shell Clam
In preparing hard shell clam for the market, they are washed with sea water graded for size, and cooled. Some clams may be taken from semi polluted waters provided they are depurated.

In the shell, hard shell clams are marketed according to size. The different sizes are “chowders” (large size), which are used to prepare chowders, fritters, or stuffed clams; “cherrystones” (medium size), which are used for baking; and:”little necks” (small size), which are used as steamed clams or for eating raw on the half shell. Hard shell clams are neither canned nor frozen in significant quantities.

Hard Shell clams may be cultured. In such instances, the bottom is first prepared by removing thick grass, stones and other debris. Predators, such as starfish, cockles, conchs and welks, are removed by raking and by towing floor mops over the bottom (to entangle starfish). The young clams, raised in tanks, are then spread over the area by scattering them from the side of the boat, using a shovel. Once seeded, the area is left undisturbed to permit the clams to grow to harvesting size. Predators may be removed from times to time. After seeding, the area may seed itself naturally.
Processing of Hard Shell Clam

The Hard Shell Clam

2008-12-03T07:49:00.000-08:00

The Hard Shell Clam
The hard shell clam is similar to the oyster in its intestinal structure, the shell is rounded symmetrically and relatively smooth on the outside, coming to a gradual peak near the hinge. The shell is quite hard and thick. Once the larvae have developed into clams that are 1/8 – ¼ in. (0.3 – 0.6 cm) in diameter, they burrow into the mud and remain just below the surface of the ocean bottom. The hard shell clam is found from the Maine coast to the Gulf of Mexico, but is most abundant off the Atlantic Coast from southern Massachusetts up to and including Virginia.

Hard shell clams may be harvested by hand (feeling of them with hands or feet and removing them by hand). They may also be removed from shallow water with clam rakes. The largest quantities of this clam are harvested with scratch rakes, with tongs similar to those used to remove oysters, or with dredges. Dredges are used in comparatively deep water and may be of the basket or water jet type.
The Hard Shell Clam

The effect of struggling

2008-11-11T06:22:00.000-08:00

The effect of struggling
It has long been known that an animal undergoing vigorous exercise has a much more active metabolism than when placid. Consider the effort that is made to ensure that cattle are slaughtered when in a calm state. When animal dies in a hyper state of metabolic activity, there are many more active enzymes and other biological components that adversely affect the subsequent spoilage rate of the slaughtered animal.

The effect of struggling is probably most profound in a fish that is caught by hook and line or gillnet and allowed to thrash in the water for some period of time. The effect is even greater when a fish has been feeding prior to being caught. During the struggling period, the digestive enzyme activity is greatly accelerated in the stomach. Since digestive enzymes in the stomach and viscera do not attack normal healthy live tissue, this effect is found after the fish is landed and stored, usually in ice, either on the vessel or subsequently during transporting or in the processing plant. The dead tissue is the walls of the stomach, intestines, or other organ is now subject to attack by the enzymes. These active materials, such as pepsin, digest all parts of the viscera, eventually perforating the walls and attacking the edible flesh. This effect known as “soft belly”: in the fishing industry, greatly reduces the shelf life of the fish and reduces the yield due to the soft flesh that must be removed during butchering and cleaning.

It should also be pointed out that the cause of more rapid deterioration in “soft belly” fish is not always due to the biochemical reaction of enzymes alone. When the viscera is perforated by poor handling method, bacteria are allowed to get into the body cavity and cause further spoilage due to bacterial action.

If a fish is pulled from water soon after being hook, the effect of struggling is almost eliminated, especially if it is killed when landed and not allowed to thrash on the deck or shore. For this reason, the effect of struggling is much more noticeable in long-lined fish allowed to thrash and die in the water than with troll-caught fish that are landed immediately after being hooked.
The effect of struggling

The Cod

2008-10-29T18:41:00.000-07:00

The Cod
Cod are found on both sides on both sides of the Atlantic and are most plentiful around Norway, Iceland, Newfoundland, Nova Scotia, and on Georges Bank off Cape Cod. In the Western Atlantic, they range from Greenland to North Carolina. Molluscs (clams, oysters, scallops, etc) are said to make up an important part of the diet of the cod, but cod also eat small fish.

By far the largest quantities of cod are caught with otter trawls in waters ranging from 300 to 1500 ft in depth. Small quantities of this species are caught with long lines, hand lines, or grill nets. When caught with otter trawls, the fish are gutted and washed on the deck of the boat. During summer months, the gills must be removed, but the head is left intact. The fish are stored in boxes or pens, in either case layered with ice.

At the processing plant, the fish are washed and filleted, skinless. The fillets are then candled (observed over a bright light) to locate and removed parasites. Fillets to be sold as fresh precooled, placed in metal tins of 10, 20, or 30 Ib, and the tins are refrigerated (mechanically or in ice) until they reached their destination. Some fillets are precooled, packed in small trays. Overwrapped with the transparent plastic, and shipped to their destination in insulated containers.
The Cod

The Anchovy

2008-10-20T17:57:00.000-07:00

The Anchovy
The anchovy (family Engraulidae) is a small herringlike fish found off the coasts of California and Mexico. It is caught in purse seines, and at on e time was used as line bait for tuna fishing and later mostly in the production of fish meal and fish oil.

The anchovy ranges over all the temperate and tropical seas of the world. Of the more than 130 varieties of anchovies, sixteen are found in United States waters. The only commercial fishery in the United States that targets anchovies for food is located on the Pacific Coast. The northern anchovy is sold there mostly as live bait and to a lesser extent as food. The bay anchovy found on eastern shore is often one of a mixture of juvenile fish taken as whitebait, but no targeted fishery exists for adults in the east.
The Anchovy

Oysters Processing

2008-10-08T19:29:00.000-07:00

Oysters Processing
Oysters are harvested with rakes, tongs, dredges, or with water jet vacuum dredges. Oysters and other bivalves, except scallops, are able to live out of water at suitable temperatures for some times. Since they can obtain oxygen from that which is dissolved in the water retained within the shell in contact with the gills. Aboard boats, oysters and clams must be held under sanitary conditions away from the bilges. The boat used to harvest bivalves should be outfitted with a chemical toilet so that growing areas will not be polluted with the human discharges.

At the processing plant, oysters to be marketed in the shell are washed in seawater which may be chlorinated, packed in sacks or barrel, cooled and shipped to restaurants. They should be held at temperatures between 32 degree F and 40 degree F. Most oysters are shucked by hand with the aid of a knife. The meats are washed or agitated in fresh potable water by air blown into the wash tank, graded for size, and packed in glass or metal containers. The filled containers are cooled and shipped to market in crushed ice.

Oysters are eaten raw from the half shell or in stews (lightly heated in milk with some butter) or breaded and deep-fat fried.
Oysters Processing

Fly Fishing

2008-09-22T17:35:00.000-07:00

Fly Fishing
Copyright © 2008 www.markinglisblog.com
The Rod
In fly fishing a fly fisherman's tackle will comprise of a rod, reel, line, leader and a variety of artificial flies to tempt that illusive fish. The purpose of this tackle is to gently yet accurately place the artificial fly or lure on the water with minimum disturbance. To achieve this result, fly fishing tackle utilizes a uniquely manufacture tapered line with an engineered light weight rod. Traditionally trout fishing and salmon fishing fly rods were manufactured out of bamboo cane with the hexagonal split cane rod being the mostly widely used from 1900 to the 1950's. From 1950 onwards the glass fiber rod started to dominate due to the lower manufacturing costs. In the late 1970's carbon fiber was invented and the weight of fly rod's plummeted, this made line weight a critical factor in the performance of the rod.

Throughout the world the trout fly rods vary quite a bit although they will usually comprise of two or three sections which can be dismantled and stored safely in a rod tube. Trout and Salmon Fly rods are said to have a tip action or a through action. Tip Action - This refers to the tip of the fly fishing rod being worked to about halfway through its length with the lower end closest to the reel doing minimal work.

Through Action - In contrast to the tip action fly fishing rod, the through action fly fishing rod will work through its entire length. The best way to find out which fly fishing rod suits you best is to go to your local retailers or trout fishing retail event where you can try the different fly fishing rods with line and leaders to determine which best suits your style of casting. The type of trout fishing water together with the species of fish being sought impacts on the required length of a rod. For example, a fisherman trying to tempt a wily Salmon will usually use a rod of between 12 and 14 feet. A lake fisherman looking for a crafty trout will usually use a rod of some 9 feet in length. The same angler if fishing a small stream could use a rod as small as 6 feet in length. Obviously the length of a rod impacts greatly on the weight of the rod. Long length Salmon rods will tend to be close to 1 lb in weight while the smaller stream rods may only way a couple of ounces. The average weight of a lake rod will be in the region of 4-5 ounces or perhaps as low as 1 ¾ ounces for the higher end of the market rods.

When using a Salmon fishing rod they are fished with both hands and the longer length allows for much greater control of the line. If you were attempt to use this kind of rod on a lake after a couple of hours you would begin to feel tired therefore, lake rods are generally much lighter allowing for longer fishing sessions.

Shorter rods are usually used on small streams for trout fishing where the cover of foliage restricts the cast somewhat. In addition to this, over shorter distances a small rod is a great deal more accurate. In summary then, choosing the correct fly rod is essential and what suits one person does not suit another's style. A fast action rod is harder for someone just starting out in fly fishing to use as the time between the forward cast and the back cast is much shorter. The longer salmon fishing rods weigh much more than the trout fly fishing rods. There are of course variations in the types of rods and the best way to find out which suits your style is to try casting.

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Oysters in United States

2008-09-17T02:35:00.001-07:00

Oysters in United States
There are five species of oysters in the United States, three on the East Coast, and two on the West Coast, one of which was introduced from Japan. About two weeks after the eggs hatch the free swimming larvae attach and cement themselves to a hard surface (rock and shell) on the bottom. To provide for this attachment, oysters growers throw materials, such as the shells of quahogs (the cultch), into the water where spawning takes place. Some time after the set (attachment), the small bivalves may be removed top areas where tidal conditions provide a better supply of food. This also allows more room for growth.

Since oysters and other bivalves may be eaten raw or without sufficient cooking to destroy any disease causing bacteria that might be present , and since they are grown near the shore, often near highly populated areas, great care must be taken to make sure that bivalve growing areas are not polluted with even traces of human excrement. Control of bivalve harvesting areas is supervised by a division of the Food and Drug Administration but must be effected by state authorities.

This control consists of tests for disease indicator bacteria on shellfish growing water and ion shellfish meats, sanitary surveys to determine that traces of sewage are not reaching the growing areas, and the licensing of shellfish dealers who must record the areas from which the valves were taken, from whom they were purchased, to whom they were sold. Some bivalves may be taken from areas that do not meet the absolute specifications for approved areas but that are not grossly polluted, provided they are depurated in bacteriological clean waters, either in the ocean or in tanks, under supervision by the state.
Oysters in United States

Otter Trawls

2008-09-07T23:48:00.000-07:00

Otter Trawls
Otter trawls are used to catch cod, haddock, flounder, and other bottom fish. The otter trawl is large, cone-shaped net that is towed behind the fishing boat along or just over the bottom. The mouth of the net is fitted with floats at the top and weight at the bottom that serve to keep it open vertically.

Attached to the towing lines, near each side of the mouth of the net, are “doors” or large rectangular wooden frame that keep the mouth of the net open in the horizontal direction. The far end of the otter trawl has a mesh small enough to retain fish of edible size but large enough to allow very small fish to escape.

After the net has been towed for some time, it is pulled up to the boat and the “cod end” is tied off with a strap. This portion of the net is then hoisted out of the water to a position over the deck, and the bottom end is opened by a line attached to a special closing mechanism which allows the fish to fall onto the deck of the boat.
Otter Trawls

Menhaden

2008-08-29T22:13:00.000-07:00

Menhaden
Four species of menhaden, sometimes called “pogy,” “bunker,” or “mossbunker,” are found in the Western Atlantic. They are fish of the genera Brevoortia and Ethmidium, two genera of marine fish in the family of Clupeidae.

They range from Nova Scotia to Brazil. Menhaden feed on microscopic plants and animals.

They are caught with purse seines when schooling near the surface of the water and removed to the hold of the power boat or carrier vessel. Aboard the boat, they may be held without refrigeration, in which case they will be brought to port within a period of 24 hrs after catching. Boats that keep these fish in refrigerated holds may remain at sea for several days prior landing the catch.

Menhaden are not used for human food. They are processed to produce fish meal and oil in the manner described for herring. In the United States, larger quantities of menhaden are caught (several hundred thousands metric tones) than that of any other fish or shellfish.
Menhaden

Long Lines Fishing

2008-08-16T20:56:00.000-07:00

Long Lines Fishing
Long Lines are used to catch halibut and in some instance, cod and haddock. The long line has a comparatively heavy central line to which short lines or “gangings” are attached right angles to the main line and at distances of every few feet.

A barb hook, which is baited, is fasted to the end of each ganging. An anchored line carrying a float and flag is fixed to each end of the central line, the anchor holding the gear on the bottom and the flag, which rests above the water surface, serving to indicate them position of the gear. In setting the long line, the float and anchor at one end are thrown overboard, and the central line, with gangings and baited hooks, is run and allowed to sink to the bottom. The anchor and float at the other end of the line are then thrown overboard.

After the set has been allowed to lie for a period of several hours, the float and anchor at one end are taken in, and the line is pulled into the boat with (for halibut) or without the aid of a rotating block or cylinder. As the fish reach the boat they are flung onto the deck, or removed from the hook by hand with or without the aid of a “gaff” (or large unbarbed hook with a short handle). As the line, with fish remove, is brought into the boat, it is coiled into tubs so that the hooks can be baited without difficulty. Long lines may be set over a distance of one mile or more.
Long Lines Fishing

Shad

2008-08-01T09:30:00.000-07:00

Shad
Shad are anadromous fish (ascend rivers to spawn) that spend the greatest part of their lives in ocean waters as far as 50 mile (80.5 km) from shore. Shad are plankton eaters and are said not to eat fish. They range from the Gulf of St. Lawrence to Florida on the East Coast, but are caught in significant numbers only from New York southward. They were brought, some years ago, to Pacific waters, and some are now caught in California. Shad are caught in rivers and their estuaries with drift grill nets. Aboard the boats, they are neither eviscerated nor iced, since they are brought to shore shortly after removal from the water.

Shad are used almost entirely as the fresh product, with only small amounts being frozen. They contain many small bones, but can be filtered to eliminate most of them from the flesh. The roe (unfertilized eggs), which prior to spawning is held together by a thin membrane, is highly prized. It is sold fresh, or packaged in moisture vapor-proof material and frozen to be sold to the restaurant trade and in this state, may be stored at 0 degrees F for 6 to 8 months. Longer storage under this condition usually results in a rancid product due to oxidation of the fats contained therein.
Shad

King Crab

2008-07-21T03:51:00.000-07:00

King Crab
This species is not a true crab but is similar to crabs in structure and habits. It is much larger than other crabs, attaining a spread of about 5 ft (1.5m) and a weight of about 24lb (10.9kg).

King crabs are caught off central Alaska to the Aleutian Islands and off the islands of northern Japan. They are harvested with large rectangular pots. Aboard boats, the crabs are held in the live state in wells of circulating seawater.

King crab meat is either canned or frozen. In canning, the whole crab is cooked in boiling water, after which the meat is squeezed out between rubber rollers. The meat is then washed, packed in cans in a weak brine, and the cans are sealed, heat processed, cooled and stored. The meat may be frozen in large block for the restaurant trade. The legs and claws are also frozen for retail outlets and restaurant.

If properly packaged and frozen to a temperature of 0 degree F or below and held at this temperature, King crab meat has a high quality storage life of at least 12 months. Lower storage temperatures provide for an even longer storage life.
King Crab

Sea Herring Processing

2008-07-04T19:45:00.000-07:00

Sea Herring Processing
The larger fish may be used for export, as there is a foreign market for this species where it is used for human food. The smaller herring, which are canned sardines, must be held in the purse seine (sometimes for longer than 24hrs) until the stomach is free from feed. This is done to prevent enzyme reaction, which would reduce the quality of the fish. Fish from nets are loaded on the boat with a large vacuum pump and are salted. More salt is added at the processing plant after the fish beheaded and eviscerated. The small herring are then reheated, placed in small rectangular cans, and subjected to steam for 18-20 min. The liquid in the cans is drained and replaced with vegetable oil. Tomato sauce, or mustard sauce; and the cans are sealed, heat processed, and cooled. The product is shelf-stable.

The larger herring are also canned whole but in larger oval cans, usually in tomato sauce. Some large herring are cut transversely into bite size pieces and packed in small cans in tomato sauces. This product is also shelf-stable.

Some herring are pickled (salt, vinegar, sugar, and spices) and packed in glass jars. Sour cream, onions, or other flavoring ingredients may be added before sealing the jars. Other pickled products include rollmops (pickled herring strips wrapped around a piece of pickle or onion) and kippered herring (salted and lightly smoked). These products must be refrigerated. Some herring are highly salted and heavily smoked, and this product is shelf stable. Large quantities of scales from the skins of herrings are recovered and used for the manufacture of pearl essence.

Sea Herring Processing

Fish Oil Supplements May Help Some Cardiac Patients While Harming Others

2008-06-07T20:31:00.000-07:00

Fish Oil Supplements May Help Some Cardiac Patients While Harming Others
Fish oil supplements may help some cardiac patients while harming others, suggests a new review of evidence compiled by St. Michael's Hospital and University of Toronto researchers.

In a systematic review of trials where patients with implantable cardioverter defibrillators used fish oil supplements, Dr. David Jenkins and Dr. Paul Dorian found significant differences among the trials, indicating fish oil may be beneficial to some patients while having a negative impact on others.

"Fish oils can have complex and varied effects on the heart," says Jenkins, a U of T Professor of Medicine who runs the Clinical Nutrition and Risk Factor Modification Centre at St. Michael's Hospital. "These effects include blocking cardiac ion channels, reducing fibrosis in response to mechanical stress, decreasing blood coagulation, and possibly altering immune function."

There is evidence from multiple large-scale population (epidemiologic) studies and randomized controlled trials that intake of recommended amounts of DHA and EPA in the form of dietary fish or fish oil supplements can reduce the risk of death, heart attack and dangerous abnormal heart rhythms in people with known cardiovascular disease, as well as potentially slow hardening of the arteries and lower blood pressure slightly. But the evidence also shows high doses can have harmful effects, such as an increased risk of bleeding. Although benefits are proposed for alpha-linolenic acid, scientific evidence is less compelling and beneficial effects may be less pronounced.

The meta-analysis reveals that studies in different patient populations with different pathophysiologies and therapeutic regimens have all produced divergent results. However, more recent data suggests that particular caution should be exercised when analyzing data from certain subgroups, such as men with stable angina. The same may also be true for patients with implantable cardioverter defibrillators who have a history of ventricular tachycardia and who are not taking antiarrhythmic medications.

"Fish oils have promise as beneficial in cardiovascular disease but our work highlights our gaps in understanding and the need for more research," adds Dorian, a cardiologist at St. Michael's Hospital and U of T Professor of Medicine University of Toronto.

Fish Oil Supplements May Help Some Cardiac Patients While Harming Others
Source: www.medicalnewstoday.com

The Sea Herring

2008-05-11T17:36:00.000-07:00

The Sea Herring
Among the various categories of fish used by humans for food, one of the most important is the family Clupeidae comprising pelagic species that travel in groups or schools near the ocean surface.

In the United States sea herring are found in ocean waters from Alaska to the state of Washington on the West Coast, and from Labrador to Cape Hatteras on the East Coast. Sea herring are plankton feeders, eating the various microscopic plants and animals (diatoms, larvae of various shellfish, etc) when very young and, as adults, eating small shrimp, small fish, and so on. When unmolested, the sea herring may live to an age of 20 years or more.

Most sea herring are caught with purse seines, but some are caught with pound traps or weirs (similar to pound traps but constructed with poles and brush). Gill nets are sometimes used to catch these fish.
The Sea Herring

Fatty fish consumption found to slash risk of dementia, Alzheimer's

2008-04-03T02:19:00.000-07:00

Fatty fish consumption found to slash risk of dementia, Alzheimer's
A new Tufts University issue of the journal Archives of Neurology has found that people with diets high in fatty fish run a significantly lower risk of developing dementia and Alzheimer's disease.

The study examined the diets and dementia levels of nearly 900 men and women who participated in the Framingham Heart Study. Researchers followed the participants for nine years, and found that 99 people developed dementia, including 71 who developed Alzheimer's disease.

The researchers examined the participants' blood levels of docosahexaenoic acid (DHA) -- a polyunsaturated omega-3 fatty acid -- and found that those with the highest DHA levels had a 47 percent lower risk of developing dementia, and a 39 percent lower risk of developing Alzheimer's, compared to participants with lower blood DHA levels.

"If you have a high level of DHA, a fatty acid found in fish, it reduced your risk of dementia by about half," said the study's lead researchers, a senior scientist and director of the Lipid Metabolism Laboratory at the Jean Mayer U.S. Department of Agriculture Human Nutrition research Center on Aging at Tufts University.

Omega-3s have long been lauded as beneficial to cardiovascular and circulatory system health. "Just as fish is good for your heart, it's probably food for your brain as well," researcher said.

Researcher study found that blood levels of DHA can differ depending on the liver's ability to convert ALA (alpha-linolenic acid, another fatty acid) into DHA. However, the greatest influence on blood DHA levels was the amount of fish consumed. The Framingham participants who ate the most fish per week had the highest blood levels of DHA, while those who ate the least fish had much lower levels. Though researcher believes supplementing the diet with fish oil capsules would be as effective as eating fatty fish -- such as mackerel, herring, lake trout, sardines, salmon and albacore tuna -- some experts believe more study is needed to determine the link between fish oil supplements and prevention of dementia.

According to consumer health advocate Mike Adams, author of "The Seven Laws of Nutrition," researcher's study shows that the oils found in fatty fish can protect the nervous system from degenerative damage. "But what most people don't know is that those same healthy oils can also be found in many plants, including chia seeds, flaxseed, avocados and macadamia nuts," Adams said.
Source: www.naturalnews.com
Fatty fish consumption found to slash risk of dementia, Alzheimer's

Temperature and fish

2008-01-24T12:59:00.000-08:00

Temperature and fish

How important the temperature to fish? To give some idea of the important of temperature , fresh caught fish will generally last about 12 days if held in ice (temperature) at about 32F or 0C) whereas they will last only about 4 days at 46F (7.8C), a temperature sometimes found in domestic refrigerators.

There are at least three reasons why fish spoil so rapidly at refrigerator temperatures. Primarily, because they are readily digestible; second, because the muscle glycogen is nearly depleted during harvesting , leaving little to be converted to acid, which would act as a preservative.; finally , because the bacteria found on fish are psychrophiles – that is, they can grow well at low temperature. Even among psychrophiles there is a range of optimum growth temperatures for different species , ant it is known that some of the psychrophilic bacteria found naturally on fish grow at such low temperature that they are reliably detected by standard bacteriological plating techniques.
Temperature and fish

Fish

2007-11-16T07:38:00.000-08:00

Fish
Fish flesh is readily digested, and it is subjected to highly active bacterial enzymes. Therefore, fish tends to deteriorate rapidly and cannot be held at temperatures above freezing for long periods. A simple principle that applies to all fresh food and especially to fish is the 3/H rules.

Handle the product strictly under sanitary conditions to keep the microbial contamination a minimum.

Handle the product at cool temperature (microbes multiply rapidly and spoilage reactions proceed rapidly at warm temperature but both proceed slowly at cool temperature.

Handle the product quickly – fish deteriorate as a function of time as well as temperature.
Fish

Fish and shellfish

2007-11-16T07:35:00.000-08:00

Fish and shellfish
Of the flesh foods eaten by humans, fish have the highest feed conversion ration. Every 1 Ib of feed yields about 0.67 Ib of fish. Fish also require much less space than other animals.

For example catfish, space requirements are about 2500 Ib per acre (2750 kg per ha); silo systems can reportedly produce about 1 million Ib of fish per acre (1.1 million kg per ha).

This fact suggests that fish for human use will eventually be produced largely by fish farming. It may be that the situation is beginning to change.

Methods of culturing oysters, clams, mussels, abalone, shrimp, crawfish, crabs, northern lobsters, salmon, catfish, carp, buffalofish, milkfish, tilapia, shad, striped bass, trout, mullet, and plaice are being investigated in various countries.

In some countries, several freshwater species (catfish, carp, trout, and tilapia) have been raised as a commercial enterprise for some years and milkfish have been raised for many years in the Philippines.

Oysters are now grown commercially in some areas, and the raising of shrimp in Japan is already commercialized.
Fish and shellfish