Origin
E 405 is obtained through a chemical process by esterifying brown algae. The resulting propylene glycol alginate is highly water-soluble and not as sensitive to acids and calcium as alginates typically are.
Usage
As mentioned, E 405 is primarily used as an emulsifier but also serves as a thickener. It should be noted that in the EU, E 405 is only permitted for specific food items. The foods to which E 405 can be added include: beer, ice cream, liqueur, baked goods, sauces, and chewing gum. The established ADI value (the allowed daily intake) is set at 25 mg per kilogram of body weight.
Risks
Propylene glycol alginate is considered harmless. In the human organism, E 405 breaks down into propylene glycol and alginic acid, with the propylene glycol being metabolized and the alginic acid not. Propylene glycol is known as a component of antifreeze.