seafood Flashcards
what are the 2 types of fish (vertebrates)
oily fish / fatty fish
and
white fish
what are the 3 types of shellfish (invertebrates)
crustaceans
molluscs
other invertebrates (sea urchins)
what are examples of oily fish
Salmon, trout, mackerel, sardines, pilchards, sprats, herring, swordfish.
Tuna does not count as an oily fish.
what is the nutritional value of oily fish
High in long-chain omega-3 fatty acids.
Good source of vitamin D. (The vitamin D source is very low for what we actually need)
Calcium and phosphorus – if bones eaten.
what are examples of white fish
Cod, haddock, plaice, Pollock, coley, dab, flounder, red mullet, whiting.
what is the nutritional value of white fish
Flesh is very low in fat (<2%) but depends on cooking method!
A source of omega-3 fatty acids, but at much lower levels than oily fish.
what are examples of crustaceans
Crabs, crayfish, lobster, prawn, scampi, shrimp.
what are examples of molluscs
Clam, cockle, mussel, oyster, scallop, octopus, squid (calamari), snail, whelks.
what are examples of other shell fish invertebrates
sea urchins (echinoderms).
what is the nutritional value of shell fish
Low in fat.
Source of selenium, zinc, iodine (this is rich is salt water tings such as seaweed too) and copper.
Some are a source of long-chain omega-3 fatty acids, but at lower levels than oily fish.
when are fish and shell fish preserved
Before refrigeration and motorised transportation,
what are the 4 ways of preserving fish and shell fish
drying
salting
smoking
fermenting
how does drying preserve fish and shell fish
Drying in the sun and wind (very lean fish and shellfish) in cold and hot climates.
how does salting preserve fish and shell fish
Salting – before or instead of drying.
Lean fish were salted then air-dried.
Fatty fish immersed in brine (very salty water) then smoked.
how does smoking preserve fish and shellfish
Smoking preserves fish and masks stale fishiness.
how does fermenting preserve fish and shell fish
Fermenting relies on naturally occurring enzymes and bacteria.
what are fish eggs
Ovaries (roes) of fish accumulate vast numbers of eggs for spawning - up to 20,000 in a salmon and several million in a sturgeon (caviar).
what are the nutritional qualities of fish eggs
Contain more fat than the fish, large quantities of savoury amino acids
what causes the bright pink and yellow colours of fish eggs
attractive pigments: bright pink or yellow carotenoids.
what are the health benefits in terms of vitamins, calories, and minerals in seafood
Good source of protein, B vitamins, iodine and calcium
Relatively few calories.
what are the health benefits for oily fish in terms of unsaturated omega - 3 fatty acids
Fatty/oily fish are rich in long chain, highly unsaturated omega-3 fatty acids which humans cannot make very efficiently from other fatty acids: eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). (there’s Not many other sources of DHA than in oily fish)
- Development and function of brain and retina
- Anti-inflammatory
- Reduces blood triglyceride levels
- Freshwater fish < Farmed fish < Ocean fish (for omega - 3 levels)
what are the health hazards with infectious and toxic producing microbes in seafood, found prior to cooking
Raw or undercooked shellfish trap bacteria and viruses as they filter water for food. We eat the digestive tract, sometimes raw!
Prevent infections by bacteria and parasites by cooking to 60oC.
Botulism bacteria produce a deadly nerve toxin.
Some viruses require temperatures >82oC to be eliminated.
Hepatitis viruses A and E cause liver damage.
Some chemical toxins produced by microbes can survive cooking, even though the microbes are destroyed, and cause food poisoning.
whats the health hazard of heavy metals being found in seafood
and what are these heavy metals found
Mercury, lead, cadmium and copper interfere with O2 absorption and transmission of nervous system signals.
what are organic pollutants found in seafood and why are they dangerous
Dioxins and polychlorinated biphenyls (PCBs) cause liver damage, hormonal disturbances and cancer in lab animals.
parasites are a health hazard in seafood, what are parasites
Animals that take up residence on ‘hosts’ and use them for shelter and nourishment, including tapeworms and flukes.
what is the health hazard of cooking seafood at high temperatures
Cooking at high temperatures transforms proteins and related molecules into highly reactive products that damage DNA and may initiate cancer.
Steam or poach fish rather than grill, fry or BBQ.
what can be does to avoid damage to seafood when cooking it at high temperatures
Before cooking at a high temperature, apply a marinade – the moisture and acidity reduces carcinogen production.
what is the recommended amount of fish to eat weekly
2 or more portions of fish a week, including 1 portion (140g) of oily fish.
how much oily fish should be consumed weekly
4 or more portions of oily fish per week.
2 or less portions of oily fish per week for women who are planning a pregnancy, or currently pregnant, or breastfeeding.
how much high mercury fish such as swordfish, shark and marlin should be consumed weekly and why
1 portion or less per week.
Children, pregnant women and women trying to get pregnant should not eat these fish. Hg (mercury) can affect a child’s nervous system.
what are the recommendations for white fish consumption
No limits, except for sea bream, sea bass, turbot, halibut and rock salmon – may contain similar levels of pollutants to oily fish.
For those who regularly eat lots of fish, avoid eating the above fish and brown meat from crabs too often.
For women who are pregnant or trying for a baby, have less than 4 cans of tuna a week or less than 2 tuna steaks per week.
Tuna has higher levels of mercury than other fish.
what are the recommendations for shellfish consumption
No need to limit the amount of white crab meat.
No recommended amounts for other shellfish.
who should avoid fish liver oil supplements and why
Women should avoid these when pregnant or trying for a baby due to the high levels of vitamin A (retinol) present.
when do seafood allergies develop
May develop at any point in a person’s life.
Once these allergies are developed , there usually lifelong and rarely outgrown
Many seafood allergies are actually intolerances
what are the milk to moderate symptoms of a seafood allergy
Hives (rash)
Tingling mouth
Swelling of lips, face, tongue, throat
Itching
Nausea and vomiting
Abdominal pain
Diarrhoea
what are the severe symptoms of a seafood allergy
Difficulty or noisy breathing, wheezing
Persistent cough
Chest tightness
Hoarse voice
Difficulty swallowing
Dizziness or collapse
Anaphylaxis
what forms of food may contain fish and shell fish that someone with a seafood allergy may not know about
Asian foods: prawn fried rice, stocks and sauces.
Rice dishes: paella, fried rice, sushi rolls.
Dips or pates: taramasalata, salmon and caviar or roe (fish eggs).
Anchovies: pizza toppings, salads, sauce.
Sauces: Worcestershire, oyster and fish sauces used in casseroles or stir fries.
Supplements: e.g. glucosamine, chondroitin, fish oil
what is the Marine stewardship council (MSC)
An international non-profit organisation that recognises and rewards efforts to protect oceans and safeguard seafood supplies for the future.
what does the blue fish label mean
Wild, traceable, sustainable.
It’s only applied to wild fish or seafood from fisheries that have been certified to the MSC Fisheries Standard, a science-based set of requirements for sustainable fishing.
what is sustainable fishing
means leaving enough fish in the ocean, respecting habitats and ensuring people who depend on fishing can maintain their livelihoods.
