Glycerin is a solvent that helps maintain food colors and flavors. 

Because it absorbs water, it is used as a humectant. It is also used as a thickener in gelatin desserts and chewing gums and added to some baked goods, fillings, beverages, and gelatinous meats. 

Glycerin is on the GRAS list, but can cause irritation to mucous membranes in some people.

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