2. Seafood structure and origin Aquatic life from fresh and salt water 24000 species of fish worldwide Can be farmed and fresh Good source of complete protein Little connective tissue = fragile flesh Low in fat Easy to digest Cooks quickly
3. classification The three main types of seafood can be classified as White fish Less 5% fat Delicate flesh Tropical waters Whiting, flathead, perch, john dory, Oily fish Between 10-25% fat Darker flesh colour Salmon, sardines, tuna, Good source of Omega-3 oils
4. Classification cont. Shellfish Have an outer shell Not as easily digested as fish Two types Crustaceans – have a hard outer shell that turns orange when cooked. Example: prawns, crayfish, crab Molluscs – have a shell that opens when cooked. Example: oysters, mussels, clams, scallops
5. Food selection Selecting fresh seafood Bright clear eyes (opaque eyes means the fish has aged) Shiny bright flesh Subtle smell but not pungent (fish should not smell fishy!) Clear liquid (milk liquid around seafood is the first stage of rot) Shellfish Purchase alive or frozen (rots just as quick as it cooks) Should slightly move when touched if alive Freezes well but cannot be refrozen
6. Food selection cont Ethical Issues Fresh versus farmed seafood availability of seafood in oceans and rivers Concerns about additives to farmed seafood Environmental impacts Climate change – change in sea levels affecting supply
7. Cuts of fish Whole Scaled and cleaned Skin, flesh and bones in tact Still looks like a whole fish Fillet Whole side of the fish Boned and usually skinned Cutlet A slice of a fish (cut opposite way to fillet) Cut through the bone
8. Nutritional benefits (chemical properties) Contains complete protein (all essential amino acids) Fat in fish is good source of Omega-3 oil assists in heart disease B group vitamins A and D vitamins (oily fish only) Minerals Phosphorus Calcium Iodine Fluorine (salt water only)
9. Physical and sensory properties raw cooked Translucent Firm to touch Clear juices Opaque Natural flakes separate Milky juices