Is propane-1,2-diol alginate vegan?

Propane-1,2-diol alginate, commonly known as propylene glycol alginate or food additive E405, is a substance used primarily as an emulsifier, stabilizer, and thickening agent. It is produced by chemically reacting alginic acid with propylene oxide. Alginic acid is a naturally occurring carbohydrate extracted from brown seaweed, such as kelp, while propylene oxide is synthesized from petroleum-based chemical sources.

Manufacturers utilize propane-1,2-diol alginate in foods and beverages where stability in acidic conditions is necessary. It commonly appears in commercial salad dressings, sauces, frozen desserts, fruit-flavored beverages, and beer, where it helps maintain foam stability.

This ingredient is vegan because all of its raw materials derive from marine plant and synthetic origins. Neither the brown algae extraction nor the chemical synthesis involves animal tissues, animal byproducts, or animal-derived processing aids.