Propylene glycol alginate (abbreviation PGA) or propane-1,2-diol alginate, is an ester made from alginic acid (E400) and propylene glycol (E1520). PGA is a multi-purpose ingredient that can be used as a thickener, stabilizer and emulsifier in food such as in salad dressings, ice cream and beer. The European food additive number for it is E405. Generally, it is safe, synthetic, vegan, halal, kosher and gluten-free.


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