Fish
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Trends
Total fish consumption was 11.7 lb per
person in 1970 and is 16 lb per person in
2005.
Of the 16.3 lb, about 11.5 lb is fresh and
frozen fish and about 4.3 lb is canned
mainly tuna and salmon
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Vertebrate - fish with fins
Lean: <5% fat in edible flesh
•
Examples: cod, flounder, bluefish, sole,
haddock, pike, perch
Fatty or not lean: >5% fat in edible flesh
Examples: eel, trout, salmon, shad,
mackerel, lake bass, sturgeon
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Shellfish or Invertebrates
Mollusks - partially or wholly enclosed in
hard shell
Examples: oysters, clams, abalone,
scallops, mussels
Crustaceans - covered with crust-like shell
and segmented bodies
Examples: lobster, crab, shrimp, crayfish
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Composition
Similar to lean meat
18-20% high quality protein
Low in fat and cholesterol
Fat is most unsaturated
30-45% omega-3 fatty acids with 8-12%
being eicosapentanoic acid (EPA)
Fish are good sources of zinc, iron, and
copper with marine fish being a good
source of iodine
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All shellfish contain glycogen - a
polysaccharide used for CHO storage in
liver and muscles.
In some fish such as clams, oysters,
and scallops, the sweet taste comes
from the glucose formed by the
enzymatic action from glycogen.
Fish protein (dried) is a good source of
proteins and is used in many parts of
the world in breads, cereals, and
crackers
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Shellfish
Should be purchased alive and/or lightly
closed
Shrimp - designated according to number
required to weigh a pound. Jumbo, large,
large-medium, medium, small.
Oysters - purchased alive in shell, fresh,
frozen, shucked or canned
Lobsters - Northern (North Atlantic Ocean
and Europe). Spiny or rock lobster absence of heavy front claws.
Raw-blue green
Cooked-red
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Crabs - blue crabs come from the
Atlantic and Gulf coasts and make up
3/4 of all marketed in U.S. Dungeness
crabs are found on Pacific coast from
Alaska to Mexico.
Scallops - swim by snapping shells
together. Adductor muscle is the only
part eaten by Americans. Europeans
known to eat entire scallop.
Shellfish are easily toughened by high
temperatures. Often simmered or
steamed for short time.
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Other Fish Products
Roe - fish eggs, most can be consumed.
Often parboiled and dipped in crumbs or
cornmeal and fried.
Caviar - sturgeon roe preserved in brine
Surimi - made from a process of
mechanically deboning fish flesh to create
fabricated fish foods. Examples: sea legs
or “crab delight”
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Finfish
Fresh fish should have firm flesh, stiff
body, tight scales. Gills are red, eyes
are bright and unsunken. With pressure
the body does not leave indentation in
the flesh. Little or no slime on exterior
and odor is fresh but characteristic
Canned fish: salmon, tuna, sardines,
shrimp, crab, lobsters, clams. Tuna
most common: packed as fancy or solid
pack, chunk style, or flaked or grated.
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Inspection and Quality
Voluntary and is done upon the request of
processor
Duties of National Marine Fisheries
Service of the U.S. Department of
Commerce
Many states have additionally
requirements
Quality is based on appearance,
uniformity, absence of defects, character
(texture), flavor, and odor
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Storage
Fresh fish is highly perishable. Must be
frozen or stored in ice until sold.
As bacteria decompose fish, a substance
called trimethylamine is released.
Trimethylamine is measured to assess the
bacteria counts in fish
Rapid spoilage also due to high enzyme
activity in fish
Store below refrigerator temperatures (30 F)
for only 1-2 days and covered tightly to
prevent contamination of other foods.
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Market Forms
Drawn fish - entrails removed
Dressed - scaled, eviscerated, heads,
tails, fins removed
Steaks - cross section of dressed fish
Fillets - side cut off fish lengthwise away
from back bones
Butterfly fillet - both sides of fillet
Fish sticks - cut from fillets or steaks or
made from minced fish
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Cooking Finfish
Both dry and moist heat methods are
used, although due to delicate structure
of tissues and low amounts of
connective tissue, dry methods are
common.
Fish should be fully cooked to avoid
sources of parasites and bacteria.
Fish is fully cooked when flakes of flesh
separate easily
Overcooking is often considered
undesirable due to dryness
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Common Cooking Methods
Frying - fillets and whole fish
Broiling - steaks and fillets
Baking - fillets, stuffed, or whole fish
Steam
Microwave
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