Something’s Fishy…

Classes and Qualities of Fish and Seafood

Food TechnologyMiss Rogers

Today’s Objectives:

o Identify the classifications of fish and seafood

o Identify the quality determinants in fish and seafood and their importance

o Here Fishy, Fishy Activity

Classifications of Fish and Seafood:

o There are different methods used to classify fish and seafood including:o Muscle textureo Edibility characteristicso Cartilaginous vs. bonyo Fresh vs. Saltwatero Migratory habitso Anatomy

Fish: Two Types of ‘em!

o How did the people know that Jaws was coming to get them?

Finfish or Shellfish?

o Identified by:o Body shapeo Number of spines and rays in finso Number and type of scales and

teetho Eye diametero Internal anatomyo Location of specific body parts

Why should you not identify by color?

o Color changes due to:o Stresso Being hookedo Being removed from the watero Environmental changeso Spawning (trout and salmon)

Finfish: 2 Types

1. Cartilaginous o Sharks, Rayso Skeletons made of cartilage rather

than bone

Finfish:

2. Bonyo 95% of all known fish specieso Catfish, bass, trout, salmon, perch,

tuna, snapper, grouper

Finfish

o Vary in size, shape, color and other physical characteristics

o All share certain physical features

Overall Structure of Finfish:

Shellfish

o Invertebrate = NO backbone!o Must have an external skeleton

in the form of a calcareous shello Mollusks and arthropods

Mollusks:

o Clams, oysters, mussels, scallops,whelks, squid and octopus

Arthropods:

o Shrimp, lobster, crab and crawfish

Chart it Out!S e afo od an d F ish

Clams

O yst e r s

S quid

O c t opus

M ollusks

S hr imp

L obst er

Cr ab

Cr awfi sh

A r t hr opods

she llfi sh

Cat fi sh

B ass

T r out

S almon

B ony

S har ks

R ays

Car t i l igenous

F infi sh

Quality of Fish: Check it Out!

o 3 Determinants:o Appearanceo Textureo Odor!!!!

Fresh Fish Qualities:

o Eyes:o Bright, clear and fullo As fish becomes stale, eyes become

cloudy and sunken

o Gills:o Red and free from slimeo Gill color fades with age from pink

to gray, brown and then green

Fresh Fish Qualities:

o Odor:o Fresh and mildo As age increases, a strong,

offensive odor develops

o Skin:o Shiny with bright colorso As fish ages, skin colors fade and

become less pronounced

Fresh Fish Qualities

o Flesh:o Firm, elastic and not separating

from the boneso As fish ages, flesh changes colors

and takes on a dried out appearance

Shellfish Qualities:

o Lobsters and Crabso Heavy for size and show leg

movemento Tail of live lobster curls under body

and doesn’t hang down when picked up

Shellfish Qualities:

o Oysters and Clamso Hard, well cupped shellso Gaping shell indicates the shellfish

is dead and is no longer edibleo Shells are graded as fancy, choice,

standard, and commercial

Indications of Poor Quality:

o Voidso Dehydrationo Discolorationo Rancidity (indicated by orange

color)o Deterioration in shrimp (soft,

mushy)o Black spot

Controlling Quality:

o Quality determined by:o Specieso Method of catchingo Handlingo Processing

o Does the consumer have control over these factors?

What the Heck Happened?

o Chemical changeso Enzymes remain active resulting in

spoilage and flavor changeso Occur during the first few days of

cold storage before bacterial spoilage begins

What the Heck Happened?

o Oxidative Rancidityo Fat content increases rancidityo Affects taste and aroma

o Bacterial spoilageo Surface slime, intestines, and gills

harbor bacteriao When fish dies, loses defense

against bacteria

Here Fishy, Fishy!

o Match the given seafood or fish cut out with the proper classification and then determine whether it is of low or high quality. Explain your answer!

Review:

o Classifications of seafood and fish

o Quality characteristicso Reasons for spoilage