Emulsifiers, Stabilisers, Thickeners
and Gelling Agents.
Lecithin is present in all living cells and is a significant
constituent of nerve and brain cells.
Commercial lecithin, most of which comes from soya bean oil,
which may be Genetically Modified, contains a mixture of phosphoglycerides
containing principally lecithin, cephalin and phosphatidyl inositol.
Other sources are egg yolk, from where it was originally obtained,
and leguminous seeds, including peanuts and maize, which also
may be Genetically Modified. Vegetarians should be aware that
it can also be obtained from animal fat.
In cells lecithin protects the membranes and the polyunsaturated
fats within the cells from oxygen attack.
As an emulsifier it lowers the surface tension of water allowing
the better combining of oils, fats and water in such foods as
chocolate, ice cream, margarine and mayonnaise. In bread and
bakery products it increases volume and also acts as an anti-staling
agent thereby extending shelf life.
In margarine it has the added advantage of preventing water
leakage, so preventing spitting when frying, and protecting
beta-carotene (E160a Vitamin A). In
chocolate it allows a reduction in the cocoa butter content,
prevents crystals forming and reduces viscosity (see E476).
Soya lecithin has the same binding ability as egg yolk lecithin
and can be used in place of eggs in many products. It also helps
powders mix quickly and easily in milk or water.
Lecithin is also a good synergist to antioxidants in fats and
oils so is often used in combination with them.
For a time it was thought that lecithin supplements could help
Alzheimer sufferers but this line of research did not lead anywhere.