Propylene Glycol Alginate
Excipient (pharmacologically inactive substance)
What is it?
Propylene glycol alginate ([C9H14O7]n esterified) is a stabilizer, thickener, emulsifier used in food products such as ice cream and salad dressing. Propylene glycol alginate is an ester of alginic acid and is obtained from algae. In propylene glycol alginate, some of the carboxyl groups are esterified with propylene glycol, some neutralized with an appropriate alkali and some remain free.
As a food additive, propylene glycol is on the U.S. Food and Drug Administration (FDA) generally regarded as safe list (not to be confused with ethylene glycol, which is extremely toxic if ingested). According the FDA, as a food additive, propylene glycol is metabolized in the body and is used as a normal carbohydrate source. Long-term use and substantial quantities of propylene glycol (up to five percent of the total food intake) can be consumed without causing toxicity. There is no evidence in the available information on propylene glycol that demonstrates, or suggests a hazard to the public when they are used at levels in food that are now current or might reasonably be expected in the future. When propylene glycol is used in foods, it is labeled as "E 1520", and in cosmetics it is labeled as "propylene glycol" without an "E" number.
 FDA’s SCOGS database; propylene glycol; SCOGS-Report Number: 27; http://www.fda.gov/Food/FoodIngredientsPackaging/GenerallyRecognizedasSafeGRAS/GRASSubstancesSCOGSDatabase/ucm261045.htm. Accessed March 17, 2012.