Quillaia Extract
What it does
Foaming agent (some soft drinks).
How it's made
From the soapbark tree.
Quillaia extract is a natural foaming agent obtained from the bark of the soap-bark tree (Quillaja saponaria), native to Chile. It is used mainly to create and stabilise the foam or "head" on certain drinks, such as some soft drinks and slush beverages, because it contains natural soap-like compounds called saponins.
It is made by extracting the milled inner bark of the tree with water, which dissolves out the saponins. The extract is then filtered and purified to remove unwanted plant material and reduce other components, and concentrated to a standardised strength; more refined grades are produced where a purer saponin preparation is needed.
The finished extract is standardised for its foaming power and supplied as a liquid or powder. The saponins act rather like a gentle natural detergent, lowering surface tension so that a stable foam forms, which is why a very small amount produces a long-lasting head on a drink.
Possible reactions
Generally safe at permitted levels.