Name: sodium alginate
Colour: light beige powder
Flavour: no flavour
Chemical composition: NaC6H7O6
E number: E401
Notes: has a slimy mouth feel if eaten straight. I just tried it and wouldn’t recommend it!
Sodium alginate is gum that is used in food, pharmaceuticals and other industries. It is known for its ability to absorb water quickly. It is insoluble in alcohol, ether and chloroform.
Where does it come from?
Alginate is found in the cell walls of brown algae. Commercial product is extracted from seaweed, including giant kelp.
How is it used?
As it is a flavourless gum it is used in the food industry as an additive in the production of gel-like foods. It is used to increase viscosity as well as an emulsifier.
You may have encountered it in ice cream (as a thickener) or pimento stuffed cocktail olives. Pimento stuffing is injected as slurry at the same time that the stone is ejected; immersing the olive in a solution containing calcium salt then sets the slurry. A similar process can be used to make “chunks” of everything including cat food through “reformed” meat or “fruit” for pies.
How is it used in molecular gastronomy?
In MG it is used to create caviar and bubbles. If attempting your own food experiments without using a recipe, start with 0.5 grams per 100mL liquid (keeping in mind it doesn’t dissolve in alcohol). Also note that successful spherification is pH dependent. The ideal pH of the cocktail or solution you want to spherise is 6. If your solution is too acidic, then you will need to add something (another chemical) to make it less acidic.
Where can I buy it?
You can buy it in our online shop, either by itself or in kit form with instructions.