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Author Topic: questions about seaweed  (Read 11522 times)

paul.fr

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questions about seaweed
« on: 26/11/2007 00:57:14 »
ermmm, this may sound stupid, but is it a weed? how does it grow and are all types safe to eat.
thanks in advance for your super answers.


 

another_someone

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questions about seaweed
« Reply #1 on: 26/11/2007 01:49:13 »
There is no plant type that is a 'weed'.  A weed is merely a plant growing in the wrong place.  A rose is a weed if you don't want roses growing on that patch of land, but it is not a weed if that is what you intended to grow.
 

another_someone

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questions about seaweed
« Reply #2 on: 26/11/2007 01:53:36 »
For the rest, I had to do my homework on wiki.

http://en.wikipedia.org/wiki/Seaweed
Quote
Seaweeds consist of several groups of multicellular algae: the red algae, green algae, and brown algae. As these three groups are not thought to have a common multicellular ancestor, the seaweeds are a paraphyletic group. In addition, tuft-forming bluegreen algae (Cyanobacteria) are sometimes considered as seaweeds.

Seaweeds are popularly described as plants, but only red and green algae belong to the kingdom Plantae). They should not be confused with aquatic plants such as seagrasses (which are vascular plants).
 

Offline Alandriel

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questions about seaweed
« Reply #3 on: 26/11/2007 16:31:48 »
Edible seaweed is back in fashion  ;D ~ and good for you too. A few to perhaps tickle your fancy....

Carrageen / Carragheen (Irish Moss) Chondrus crispus

Carrageen / Irish Moss is one of the most widely used seaweeds throughout the world. It is one of the seaweeds that you will have eaten - probably without knowing it! It is E numbers E406,E407 and E407a. It was given "E number" classification in the 1970s though the recent general movement has been away from E numbers, it is one of the "natural" E numbers - E400 to E420.
This seaweed makes a lovely dessert, refreshing drink and was traditonally used as an old cough, cold and flu remedy (simply boil up with water, sugar and lemon and drink!).

Uses :

- Directly as a food
- As an emulsifier / stabliser
- Contains Retinol and derivatives (vitamin A), amino acids, minerals / vitamins, protein
- Can be used a cough remedy (traditional use)
- Source of Hydrocolloids
- As an animal feed  - contains protein




Dulse / Dillisk (Palmaria palmata)

Dulse can be eaten raw - it is traditionally eaten as a snack food in Northern Ireland and along the North and West Coasts of Ireland.

Hebridean Dulse Broth   - Serves 3 - 4

Need : 25 g dried dulse, 1 medium potato, 25 g butter, 0.5 - 1 tsp lemon juice, Salt and Pepper, 750 ml (1.25 pint) milk, crusty bread
 
Place dulse in a bowl of water and leave for 5 - 10 mins. Drain and put into a saucepan with water and boil for 10 mins. Peel and boil the potato and mash. When the dulse has cooked, drain. Mix in the mashed potato, butter and 0.5 tsp of the lemon juice. Season. Gradually stir in the milk and return to heat. Gently simmer for 20 mins, stirring often. Check seasoning and if desired add rest of the lemon juice. Serve with crusty bread.




Kelp / Kombu / Konbu / Haidai (Laminaria digitata)
also Laminaria saccharina -> sweet Kelp / Kombu Royale




Its E Numbers are E400 to E405 - and produces alginates.
Known as oarweed in Ireland a traditional use was as fertiliser but other brown seaweeds such as Ascophyllum nodosum and Fucus serratus are now gathered for their nutrient content. Kelp / Laminaria was also gathered and burnt for "potash" in the 18th Century. In Japan and China, Kelp / Laminaria is used to make Dashi - a traditional soup stock and is used extensively in cooking. It can also be added to root vegetables to reduce down their cooking time.

Dashi - Traditional Japanese Soup Stock (Makes 1 Litre)

For Vegetarians & Vegans use twice as much Kombu / Kelp and omit Bonito Flakes.
Need : Sheet of dried Kombu / Kelp , 1 litre water, 15 g Bonito Flakes

Make a few slit in the kelp sheet and cook in the water on a medium heat. Remove just before boiling. Add bonito flakes, bring back to the boil and strain.






Sea Lettuce / Ulva lactuca


This is a green seaweed - one of 1200 species found globally.

Uses :

- As a food - used within salads and as a garnish
- Contains - ash, carbohydrates, fibre, lipids, protein
- As a mineral supplement - contains ascorbic acid (vitamin A)
- gout treatment - traditional use
- Source of iodine
- As an animal feed and as a fertiliser
- Used to make paper




Sea Spaghetti / Himanthalia elongata


This brown seaweed can be eaten like normal spaghetti
- just boiled for 10 - 15 mins and added to pasta or chopped up within a salad


 ;D

 

Offline Alandriel

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questions about seaweed
« Reply #4 on: 26/11/2007 16:49:20 »
There are a few seaweeds that will give you an upset stomach so do be careful what you get
(get educated first properly or get your harvest checked).
There is one that you have to avoid though:




Lyngbya majuscula  - mermaid's hair


As far as I know the only poisonous seaweed, a filamentous, blue-green algae also called fireweed that causes skin irritations (seaweed dermatitis) in humans. Worse, if it blooms and overpopulates areas it chokes coral reefs and pretty much all other marine life.

Lyngbya majuscula is a benthic filamentous marine cyanobacterium, which in recent years appears to have been increasing in frequency and size of blooms in Moreton Bay, Queensland. It has a worldwide distribution throughout the tropics and subtropics in water to 30m. It has been found to contain a variety of chemicals that exert a range of biological effects, including skin, eye and respiratory irritation. The toxins lyngbyatoxin A and debromoaplysiatoxin appear to give the most widely witnessed biological effects in relation to humans, and experiments involving these two toxins show the formation of acute dermal lesions. Studies into the epidemiology of the dermatitic, respiratory and eye effects of the toxins of this organism are reviewed and show that Lyngbya induced dermatitis has occurred in a number of locations. The effects of aerosolised Lyngbya in relation to health outcomes were also reported. Differential effects of bathing behaviour after Lyngbya exposure were examined in relation to the severity of health outcomes. The potential for Lyngbya to exhibit differential toxicologies due to the presence of varying proportions of a range of toxins is also examined. This paper reviews the present state of knowledge on the effects of Lyngbya majuscula on human health, ecosystems and human populations during a toxic cyanobacterial bloom. The potential exists for toxins from Lyngbya majuscula affecting ecological health and in particular marine reptiles.

PMID: 11757852 [PubMed - indexed for MEDLINE] Reference


 

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questions about seaweed
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