Fish and Shellfish Chapter 15
Dec 16, 2015
Fish and Shellfish
Chapter 15
Objectives
• List methods for harvesting seafood
• Explain the purpose of the green sheet
• Summarize the many quality points that should be inspected when receiving seafood
• Differentiate between shellfish and bonefish
Objectives (cont’d.)
• Define the term mollusks
• Compare the differences between univalves and bivalves
• Define the terms crustaceans and cephalopods
• Distinguish among roundfish, flatfish, winged fish, and eels
Objectives (cont’d.)
• Identify the various market forms for shrimp and crab
• List the various market forms for fish
• Describe the proper method for icing fish for storage
Harvesting Seafood
• Seafood harvesting methods– Foraging for them in their natural habitat– Raising them in pens, ponds, or tanks
• Harvesting method has an impact on fish habitat and product
• Some methods selectively capture certain species; others are nonselective
Fish Harvesting
• Harvesting methods– Gillnetting– Handline– Harpooning– Purse seine– Hook and line– Trawling and trapping
Fish Harvesting (cont’d.)
15.2a A purse seine loosely surrounds a school of fish
15.2b The seine net is “pursed” to capture the fish
Fish Harvesting (cont’d.)
• Fish aquaculture– Open-ocean cages or net pens
• Used to hold large stocks of fish• Method can pollute surrounding waters and
threaten wild stock with disease
– Tanks, ponds, and raceways• Free-flowing water from rivers and streams are
diverted into raceways• Pumps aerate water in ponds and tanks
Shellfish Harvesting
• Harvesting methods– Diving– Dredging– Trapping and pots– Tongs and rakes
15.5 Trapping fish in pots
Shellfish Harvesting (cont’d.)
• Shellfish aquaculture– Beach culture
• Uses sand filled pens; minimal habitat impact
– Suspended cable or bags• Uses suspended surface areas upon which
filter-feeding shellfish grow• No impact on surrounding habitat or other
species
Buying and Storing
• Green sheet– Name for market news reports issued by
the National Marine Fisheries Service• Lists weekly prices of fresh and frozen seafood
• Similar reports include: – Boston blue sheet (fish blocks and fillets)– Seattle sheet (salmon)
Buying and Storing (cont’d.)
• Similar reports include: (cont’d.)– New Orleans sheet (shrimp) – Los Angeles sheet (tuna)
• Seafood grading is voluntary– Grades are A, B, and C
• Food service establishments should inspect fresh fish upon arrival
Buying and Storing (cont’d.)
• Inspection factors– Smell– For whole fish: inspect eyes, gills, gut
cavity, slime, skin, and temperature– For shellfish, ensure shells are closed
• Tap an open shell to see if it closes (indicates product is still alive)
Packaging
• Most common seafood packaging methods– Block frozen– Cello wraps– Individually quick frozen (IQF)– Layer packs– Shatterpack
Caviar
• Sturgeon roe (eggs)
• Major types of caviar– Beluga, osetra, and sevruga
• Fish roe is harvested from fish while it is still alive– Then mixed with salt to keep eggs from
clumping (malossol)
American Caviar
• Types of caviar made from U.S. freshwater fish include:– American and lake sturgeon– Hackleback and white sturgeon– Paddlefish, salmon and whitefish roe– Trout, bowfin and lobster roe
Imported Caviar
• Caspian Sea provides 90 percent of caviar available on the world market
• Types– Beluga, sevruga, and osetra sturgeon– Tobico sushi, wasabi, and kaluga caviar
Fish
• A vital food source for people worldwide
• 20,000 known species of fish
• Identified in many ways– Freshwater or saltwater– Large or small– Oily or flaky– Thin or meaty
Roundfish
• Most common types of fish– Populate salt and fresh waters
• Common types of roundfish– Smallmouth and largemouth bass, carp,
European pike perch, sauger, walleye, perch, trout, mullet, monkfish
Roundfish (cont’d.)
• Common types of roundfish (cont’d.)– Sea bass, sardine, anchovy, herring,
mackerel, swordfish, salmon, cod, haddock, smelt
– Tuna• May be labeled white tuna (albacore) or light
tuna (bluefin or yellowfin)
Flatfish
• Named because eyes are on same side of the head
• Types of flatfish– Plaice, flounder, halibut, sole, turbot
Winged Fish
• Skate– Thin fish with long tail and fins that look like
wings– Edible portions are the wings, the cheeks,
and the liver– Boneless flesh is pinkish or off-white;
resembles scallops
Eel
• Has cylindrical body with small oval scales embedded in the skin
• Popular in Japan
• Cut into fillets, slices or pieces– Sold fresh, smoked, marinated, or in cans
• Flesh is firm and fatty– Easy to debone; extremely perishable
Market Forms of Fish
• Whole fish
• Drawn
• Dressed
• H&G
• Loin
• Fillet– Thin, medium,
and thick
• Steak
• Fish sticks and patties
Crustaceans
• Shellfish with external skeletons and jointed legs
• Thousands of species, but only a few are commercially viable– Crab, shrimp, lobster, crayfish
Crab
15.9 Dungeness crab
Source: Randy van Dam 2008
15.21 Snow crab legs and claws
Shrimp
• Various market forms of shrimp– Green head-on– Green headless– Peeled– PUD– P&D– Shell-on cooked
Lobster
• Market forms of lobsters– Maine lobster (American or true lobster)– Spiny lobsters (Rock or Florida lobsters)
• Should be kept alive until needed for cooking
• Does not freeze well
• Tails may be cold or warm water
Crayfish
• Known as freshwater lobsters, crawdads and mudbugs– Most come from Louisiana– Available live or frozen whole
• Meat may be kept frozen up to two months– Live crayfishes in refrigerator for 24 hours
Mollusks (Molluscs)
• Types of mollusks– Bivalves
• Clams, oysters, mussels, and scallops
– Univalves• Conch and abalone
– Cephalopods• Squid, octopus, and cuttlefish
Clams
• Found in sand or mud close to shore– Harvested with hand tools
• Species of hardshell clams– Southern quahog, Northern quahog
• Littleneck, Cherrystone, and Chowder
– Steamer clams
• Sold live, fresh, or frozen
Oysters
• Grow mainly in tidal mudflats
• Shellfish sanitation program– Monitors oysters for contamination from
viruses, bacteria, and “red tide” toxins
• Popular standard types– Eastern oyster– European flat oyster
Oysters (cont’d.)
• Popular standard types (cont’d.)– Kumamoto– Olympia– Pacific (Japanese)
• Oysters have a fairly long shelf life– Up to two weeks– Should be consumed when fresh
Mussels
• Subject to controls of Shellfish Sanitation Program
• Cheap and plentiful
• Sold by the bushel bag– Weighs about 45 lb. 15.29a Mussels
Source: Randy van Dam 2008
Scallops
• Muscle holding the two halves of the scallop shell together
• Only available as chucked– Whole scallops cannot be opened without
commercial equipment
• Large quantities of frozen scallops are thawed and sold as fresh
Conch
• Large sea snails – Bahamian or
Caribbean– New-England type
• Becomes more tender with extended cooking
15.31 Conch shell and conch meat
Source: Randy van Dam 2008
Abalone
• One of the most expensive varieties of seafood– Prime target for cheaper substitutions– Giant squid or cuttlefish may be passed off
as abalone
• Sold cut into round steaks
• Must be cooked briefly, or it toughens
Squid (Calamari)
• Available in a variety of market forms– Fresh, frozen, dried, and canned– Fresh squid should be moist, but firm
• With a faint seawater odor
• Clean the squid prior to use– When sold fresh or thawed
• Very long shelf life if handled with care
Octopus
• Flesh is firm and flavorful– Small animals are best– Pound tough flesh of large octopus with a
mallet– Flesh of certain species is poisonous
• Usually cleaned and tenderized before it is sold
Cuttlefish
• Common in Europe and Asia
• Measures between six and ten inches
• Choose fresh cuttlefish with moist, firm flesh that smells faintly of the sea– Also sold frozen or canned
• White flesh is very firm; slippery skin is difficult to remove
Sea Urchin
• Edible portion of the sea urchin is located under its mouth– Consists of five sexual organs known as
the “coral”
• Sold whole or ready to serve and extremely perishable– Look for firm spines and tightly closed
mouth holes
Sea Cucumbers
• Found on the sea floor worldwide
• Considered a delicacy in Far East countries
• Often purchased dried and rehydrated before use
• Used in soups, stews, and braised dishes
Smoked Seafood
• Process by which salted seafood are flavored in a drying oven– Dense smoke passes around and through
the product
• Good product made from good fish
• Basic methods of smoking include hot and cold
Market Varieties of Smoked Seafood
• Includes:– Bloaters, buckling, cod and haddock fillets,
eels, finnan haddock, herrings, kippers, mackerel, oysters, pollock, sablefish, trout, whitefish
– Smoked salmon: most popular; several varieties
Seafood Analogs
• Substitutes for meat-based proteins– Burgers– Hams and loaves– Hot dogs– Sausages
Summary
• There are various methods of seafood harvesting
• Fish may be categorized as roundfish, flatfish, winged fish, eel, and shellfish
• Visually inspect incoming fresh fish
• Shellfish Sanitation Program monitors shellfish safety