Lecithin
What it does
Emulsifier.
How it's made
Extracted from soya beans, sunflower or egg.
Lecithin is a natural emulsifier — it helps oil and water mix and stay mixed — used in chocolate, margarine, baked goods and many other products to improve texture and stop ingredients separating. It is a phospholipid, the same class of molecule that makes up cell membranes, so it occurs naturally in living tissues.
Most food lecithin is extracted from soybeans, with sunflower and rapeseed increasingly used as alternatives. During the processing of the oil, the crude oil is treated with a little water so that the lecithin swells and separates out (a step called degumming); this gummy lecithin fraction is then dried and refined into the finished emulsifier.
The recovered lecithin is standardised and may be further purified or modified to tune its properties for particular foods. Because it comes from soy or sunflower, its source is declared on labels (soy lecithin being a consideration for people with soy allergy), and it is one of the most widely used natural emulsifiers.
Possible reactions
Soya- or egg-derived versions are allergen concerns; declare source.