CHRM 1130 PROTEIN BASICS
Finfish
Chapter 19Pgs.46
Ingredient and Materials Knowledge Goal:
1.
Identify an assortment of fin fish to include flat fish and round fish and
list the general characteristics of each type
2.
Differentiate between bony and non-bony (cartilaginous) fin fish and
identify some examples of each.
3.
Discuss market forms and availability of fin fish.
4.
Identify wholesomeness and quality standards in fin fish
5.
Discuss receiving, handling and storage methods for fin fish
6.
Define an assortment of freshness checks for fin fish
7.
Research aquaculture to develop an understanding of the importance of
renewable fish stocks.
Technical Goals:
After studying this chapter, the student should be able to do the
following:
1. Dress, fillet and fabricate fin fish, either round or flat.
2. Demonstrate scaling of a fish
3. Practice knife skills
KEY TERMS
Drawn
Goujonette
Steak
Dressed
Tranche
whole (in round)
Filet
Pave
wheel
Myocommata
Myotomes
Gape or belly burn
DEFINITION OF FINFISH:
Any of the thousands of species of aquatic vertebrates with fins for swimming and
gills for breathing. Found in saltwater and freshwater worldwide most are edible.
Finfish are classified by bone structure as flatfish or roundfish.
Flatfish are characterized by asymmetrical compressed bodies, with both eyes on
the top of their head and a dark top skin. They swim in a horizontal position and
are generally found in deeper ocean waters; examples would be flounder, halibut
and turbot.
Round fish are characterized by round, oval or compressed bodies with eyes on
either side of their heads. They swim in a vertical position and are found in
freshwater and saltwater environments; examples would be catfish, cod and
salmon.
Anatomy and Physiology
The importance of understanding basic fish structure.
A. Skeletal system.
1 . The skeleton of bony fishes is made of bone and cartilage.
2. The skeleton of a bony fish gives structure, provides protection, assists in leverage, and is a
site of red blood cell production.
3. Bony fishes have skeletons that are almost completely calcified. The vertebral column,
cranium, jaw, ribs, and intramuscular bones make up the bony fish skeleton.
The vertebral column, cranium, jaw, ribs, and intramuscular bones make up the bony fish skeleton.
B. Muscular system.
1 Tail and trunk muscles.
a. The muscles of the tail and trunk consist of a series of muscle blocks called myotomes.
The myotomes usually resemble the letter "W" tipped at a 900' angle.
b. The myotomes are separated by connective tissue called myosepta.
c. The horizontal septum separates the myotomes into dorsal (or epaxial) myotomes and
ventral (or hypaxial) myotomes.
Muscle blocks called myotomes are separated by connective tissue called myosepta.
2. Jaw muscles.
Jaw muscles usually consist of adductor muscles that close the jaw and abductor muscles that
open the jaw.
3. Fin muscles.
The fin muscles consist of abductor and adductor muscles that move the fins away from and
close to the body, and erector muscles that provide stability and flexibility in the fins.
C. Nervous system.
1 . The nervous system of fishes is poorly developed compared to that of higher vertebrates.
2. A bony fish's brain is divided into three sections: the forebrain, the midbrain, and the
hindbrain.
a. The forebrain is responsible for the bony fish's ability to smell. Bony fishes that have a
good sense of smell, such as eels, have an enlarged forebrain (Bond,1979).
b. The midbrain is responsible for vision, learning, and motor responses. Blind bony
fishes, such as blind cavefishes (family Amblyopsidae), have a reduced midbrain (Bond,
1979).
c. The hindbrain contains the medulla oblongala and cerebellum, which coordinates
movement, muscle tone, and balance. Fast-swimming bony fishes usually have an
enlarged hindbrain (Bond, 1979).
3. The spinal cord and a matrix of nerves serve the rest of the body.
D. Cardiovascular system.
1 . Bony fishes have a heart with two chambers: the atrium and the ventricle. The venous side of
the heart is preceded by an enlarged chamber called the sinus venosus. The arterial side of the
heart is followed by a thickened muscular cavity called the bulbus arteriosus.
a. The sinus venosus receives unoxygenated blood from the body. A valve at the end of
the sinus venosus opens into the atrium.
b. The atrium has thick, muscular walls. The atrium receives unoxygenated blood and
pumps it into the ventricle.
c. The ventricle is the largest and most muscular chamber of the heart. When the ventricle
fills with blood it constricts and forces the blood through the bulbus arteriosus.
d. The bulbus arteriosus is a valve or series of valves that control blood flow out of the
ventricle and into the ventral aorta. Blood passes through the bulbus arteriosus to the
ventral aorta. From the ventral aorta, blood flows to the gill filaments, where it is
oxygenated.
e. The spleen, kidney, and bones are sites of red blood cell production.
2. Oxygenated blood flows from the gill filaments to the organs of the head and body. A
complex system of arteries, veins, and capillaries circulates blood through the body.
3. Some tunas (family Scombridae, tribe Thunnini) maintain a body temperature several degrees
higher than that of the surrounding water. This heat is due to the modified circulatory system
associated with the red muscle.
a. As red muscle functions, it generates heat. Muscle-generated heat warms the blood
circulating through the red muscle, which then travels back to the heart through veins.
Thus, blood returning to the heart from the muscle is warmer than blood traveling from
the heart to the muscle.
b. Due to the nearness of arteries and veins, heat passes from warmer veins to cooler
arteries within the fish's body, rather than dissipating to the cooler environment. This
modified circulatory system retains heat in the red muscle.
c. A higher body temperature is an adaptive advantage in that it provides extra power for
high-speed swimming.
d. A similar modified circulatory system warms the brain and eye of some species of
tunas (family Scombridae, tribe Thunnini) and billfishes (family lstiophoridae).
E. Digestive system.
1 . The esophagus in bony fishes is short and expandable so that large objects can be swallowed.
The esophagus walls are layered with muscle.
2. Most species of bony fishes have a stomach. Usually the stomach is a bent muscular tube in a
"U" or "V" shape. Gastric glands release substances that break down the food to prepare it for
digestion.
3. At the end of the stomach, many bony fishes have blind sacs called pyloric caeca. Although
the exact function of the pyloric caeca is unknown, it probably functions both in digestion and
absorption of food.
4. The pancreas secretes enzymes into the intestine for digestion.
5. The intestine is where the majority of food absorption takes place. The length of the intestine
in bony fishes varies greatly. Herbivorous bony fishes generally have long, coiled intestines, and
carnivorous bony fishes have short intestines.
6. The digestive system terminates at the anus.
F. Respiratory system.
1 . Water enters the gill chamber through the mouth. A bony fish can remain motionless and
breathe by pumping water over its gills by opening and closing its mouth.
2. Blood in the gill filaments absorbs oxygen from the incoming water.
3. Water exits through the gill openings located under the operculum.
4. Lungfish must return to the surface to breathe air. A lungfish swallows air to fill up an air sac
or "lung." This lung is surrounded by veins that bring blood to be oxygenated. Its gills alone can't
keep a lungfish supplied with enough oxygen to live. Other species such as tarpon (family
Elopidae) can gulp air at the surface to supplement their oxygen demand.
5. Some species of bony fishes can absorb considerable amounts of oxygen through their skin
(Bond, 1979).
G. Swim bladder.
1 . Many species of bony fishes have a gas-filled bladder called a swim bladder.
2. The swim bladder originally developed as an organ of respiration, as evidenced by the "lung"
of the lungfishes.
3. In modern bony fishes that possess a swim bladder, the organ serves principally in maintaining
neutral buoyancy. 4. In some fishes the swim bladder has adapted to function as a sound
amplifier.
H. Osmoregulation.
1. Both marine and freshwater fishes must regulate the movement of water across their body
surfaces.
2. The tissues of marine fishes are less salty than the surrounding water.
a. Water is continually leaving the body of a marine fish through its skin and gills.
b. To keep from becoming dehydrated, a marine fish drinks large amounts of water and
produces a small amount of concentrated urine. In addition, its gills are adapted to secrete
salt.
3. The tissues of a freshwater fish are saltier than its surrounding environment.
a. Water is continually entering the body of a freshwater fish through its skin and gills.
b. Freshwater fishes do not drink water, and they produce large amounts of dilute urine.
What are some of the best reasons for learning to clean and prepare a wide variety
of fish?
* More people have learned to eat and enjoy fish because it is perceived to be
healthful alternative to red meat* New information on some fish has caused
alarm…fish higher up the food chain such as shark, swordfish and some tunas have
a high amount of mercury in the flesh. It is advised to eat these types of fish
rarely, no more than once a month. Salmon, shell fish and smaller fish are deemed
safe as the amounts of mercury in these fish is minimal.
* Fish is widely available and of high quality in Midwest= become knowledgable of
the product.
* Fresh is still always best, however, properly frozen product is also acceptable.
Fish is better eating than the alternative forms available. Learn how to fabricate it
and save money and insure that your product is of peak quality.
Are there differences in the way that the two classes of fish should be handled
for fabrication and cooking? You may wish to keep in mind that fish cuts are
few and species are many while meat cuts are many and species are few.
IS IT FRESH? HOW TO TELL IF A FISH IS FRESH
When purchasing fish it is critical to understand that most fish that is labeled
fresh has been out of its native waters for up to 14 days.
Really fresh fish had many indicators to its freshness.
1. SMELL- Should smell like the sea, clean, or like cucumbers when really
fresh.
2. APPEARANCE-Glossy, slightly natural slime still attached…not sticky
slimy.
3. TEXTURE-Firm, bounces back. Doesn’t leave a finger indentation
4. GILL COLOR- Bright red to bright pink…if brown and discolored, very
old fish.
5. BELLY BURN OR LACK OF GAPING-There should be NO gaping of the
flesh, otherwise called belly burn. Found in fish that is old.
6. NO BRUISES OR MARKS-No mishandling on the boat
7. SKIN BRIGHT-True to color and bright, not faded or dull
8. SCALES TIGHT- Scales loosen with age and decomposition.
9. EYES CLEAR AND BULGING-Clear..dull eyes signify age
MARKET FORMS OF FISH:
Fish is available in many forms at the market. Some can be purchased
ready to cook, while others require special preparation. Below is a list of the
market forms of fish.
Whole or round -- This type is marketed just as it
came from the sea. Before cooking, the fish must be scaled
and eviscerated (internal organs removed). Usually the
head, tail, and fins are removed prior to cooking.
Drawn -- The viscera and entrails are removed. The
fish must be scaled. Again the head, fins, and tail are
usually removed before cooking.
Dressed or pan-dressed -- The viscera are removed.
The head, tail, and fins are usually removed. The fish is
scaled, free of blood, and ready to cook.
Steaks -- Steaks are cross-section pieces cut from a
large dressed or whole fish, commonly 1/2" to 1 inch thick.
A cross- section of the backbone is the only bone in the
steak.
Fillets -- Fillets are slices cut lengthwise from the
sides of the fish. They contain no bones or other wastes,
however the skin, with scales removed, may be left on one
side. A single fillet is the flesh cut from only one side
of the fish. Butterfly fillet is the name for two single
fillets held together by uncut flesh and skin.
Portions or sticks -- These are pieces cut lengthwise
or crosswise from fillets or steaks. Most often they come
in equal size portions about 1 inch wide to 3 inches long.
Canned -- Several varieties of fish are canned. Tuna,
salmon, mackerel, and fish products are processed in this
manner. They can be stored on a shelf and are ready to
use.
HANDLING FRESH FISH FOR FABRICATION:
SCALING, PANDRESSING
essentially the same for either class of fish, either flat or round. Start at the tail
for scaling=do it while the fish is still whole if possible.
Whole fish needs to be gutted firs, wash, remove fins and scale.
FABRICATING
–
PROCESSING FISH INTO MARKETABLE PORTIONS
filleting/cutting tranches – sides of fish removed, no spine or bones: two for
small fish or round fish, four for large flat fish such as halibut, tuna, sword fish.
skinning * -
removing skin for easier eating and cooking-skin is left on for fish that is broiled.
Skin acts as a protection against the high heat.
pin boning –
removing side feather bones found on salmonae style fish. Use needle nose
pliers or tweezer made for this purpose.
cutting steaks –
portion cut of fish with center spine bone – fish is laid on its side and cut
into ½ to ¾ inch sections or steaks.
* Generally, fillets of fatty fish stay together better in cooking with skin intact.
Fillets of lean fish should be skinless to insure quick, even cooking.
STORAGE-
all fresh seafood should be consumed as soon as possible.
FRESH FISH - Fresh fish fillets should retain their true colors; pearly white, pink,
reddish or meaty. Browning or curling on the edges means they have been stored
too long. Hold fillets on ice loosely wrapped. Tight wrapping can cause a fetid odor
to develop because air is trapped inside.
FROZEN FISH - Thaw frozen fish slowly in the refrigerator. Never refreeze fish
one it has thawed. If you freeze fish yourself, it should be fresh and wrapped
exceeding well. Keep fatty fish frozen less than one mont and lean fish frozen less
than two months. Commercially frozen fish will last 3 months. Large pieces last
the longest.
*Why shouldn’t thawed fish be refrozen?
Water expansion during freezing breaks cell membranes and damages the texture
of the fish. Quick freezing and slow thawing minimizes the damage. Refreezing
causes more damage thus ruining the flesh.
- Choose from bake, broil, grill, fry, steam or poach methods. Generally,
use bake or broil for fatty fish and saute, poach or steam methods for lean ones.
Fatty is defined as 5% oil content or more. Fatty fish tend to have a stronger
flavor and more calories per serving that lean fish.
COOKING
Don't overcook your fish! Most people cook fish until it flakes and that's too late.
By the time the connective tissue (myocommata, for bonus points) breaks down the
actual meat is overdone. You want to pull it off the heat just before it flakes and
carry over heat will do the rest.
What are some common examples of fatty fish?
Salmon, catfish, white fish, mackeral, tuna
What are some common examples of lean fish?
Halibut, swordfish, shark, cod, bass, pike, walleye, perch, flounder, haddock
COOKING TECHNIQUE FOR FISH:
Realize that any fish can be cooked in any way
BAKING:
* 350 degrees to 400 degrees 10 minutes per inch
* lower temps for larger fish or pieces, higher temps for smaller pieces
* protect, moisten, with sauce and or crumbs
BROILING:
* dredge in flour and coat with oil to prevent sticking
* thin cuts should be cooked on one side
* char broil one side to mark it and finish in oven at 400 degrees-best for smaller
pieces
SAUTEING/PAN FRYING:
* coat with flour, dip in milk first.
* thin cuts work best for saute
* quick fry in small amount of fat in a hot hot pan
POACHING/SIMMERING:
* start with hot stock or court bouillon if small pieces, cold if large, use a rack to
support or cheese cloth to lift fish and avoid breaking it.
What about shallow poaching vs. submersion poaching?
Court bouillon – short broth is the meaning of this word. H20, herbs, and acid,such
as wine, vinegar or lemon juice, use for submersion poaching as its cheaper.
Fumet and wine - reduce poaching liquid 25% poach fish in this reduction and then
add more fumet, and cream to finish. Use for shallow poaching as it is quicker and
liquid will reduce more quickly.
STEAMING: sweat fish and serve in its own juices Etuver is the French word for
this method.
En papillot is a way to steam fish in its own wrapper.-baked in oven surrounded by a
paper wrapper, juices and steam are trapped and cook fish.
How will you know when the fish you are cooking is done?
1. flesh is opaque, not translucent
2. barely flakes with no gaping cracks
3. bone separates easily and is not pink
4. high quality fish such as salmon does not need to be completely “done” can be
served medium rare.
5. allow 2 to 10 minutes an inch depending upon the method and type of fish
cooked and your expertise. 145 degrees is max.