Propylene Glycol Alginate
The short version
A modified alginate that stays soluble in acid — thickens dressings and stabilizes the foam head on beer.
It's widely considered safe at the amounts used in food, so we mark it green. The Safety section below has the details.
Where it comes from
Alginic acid esterified with propylene oxide (propylene glycol) — a chemically modified seaweed alginate.
How it's used
Emulsifier, thickener, and foam stabilizer that tolerates acid and calcium far better than plain alginate. Stabilizes salad dressings and acidic drinks, and — notably — the foam 'head' on beer.
Safety profile
ADI 70 mg/kg body weight (JECFA). The propylene glycol portion is metabolized normally; considered safe within that limit.
Physical & chemical properties
White powder, soluble in water and in dilute acid, staying stable at low pH where ordinary alginate would precipitate.
Regulation worldwide
Permitted in the EU, the US, and globally with an ADI.
Educational information only. Not medical or dietary advice.