Propylene glycol is a popular ingredient for food because of its versatility and its extremely low toxicity. As a matter of fact, the US Food and Drugs Agency (FDA) approve it as an ingredient for human and animal consumption. Listed below are some of its special properties:
Humectant
A humectant absorbs and retains water to keep products from drying out. To lengthen shelf life, the sweet alcohol is added to chewing gums, mints, dog food, biscuits, and candies. Snacks that are exposed for too long can now maintain their moisture.
Emulsifier
An emulsifier stabilizes a mixture by binding two or more liquids that are normally immiscible. It forms a layer around oils contained in a mixture in order to keep them from gathering in clumps. Oils are dispersed into droplets, and the process preserves the mixture in turn. Soft drinks and mayonnaise take advantage of this property when propylene glycol is added.
Solvent Carrier
Some ingredients need a vehicle to be active in a mixture. Propylene glycol is a suitable carrier because of its neutral nature. It carries flavors and colors that give food their unique appearances and tastes. It also stabilizes beer, salad dressings, and pre-made pastries.
Thickening Agent
A thickener increases a product's viscosity or bulk without modifying substantially its other properties. This is very important especially with food as the additive should not in any way affect its taste or aroma. Propylene glycol adds the desired volume for cheeses, ice cream, and yogurt.
Although it is popular as a food ingredient, the organic glycol has also found its way to different health-sensitive applications in which moisture is a concern.
Cosmetic and Toiletries:
The food grade glycol is one of the most chosen additives for cosmetic products. It provides lipsticks with its consistent texture, preserves the consistency of oil-in-water emulsions, provides fixative for perfume scents, and enhances the foaming ability of shower gels.
Animal feeds:
Because this alcohol absorbs moisture, it also keeps animal feeds moist, fresh, and chewy. This makes it easy for dogs and livestock animals to digest the food. This is even useful during winter as it helps feed reduce its freezing point and preserve for sustained periods. So even at sub-zero temperatures, the feed is still viable for eating. Propylene glycol is also an available energy source.
Pharmaceuticals:
For drugs to be potent, the active ingredients should be homogenized in a solution and still be effective upon application. Propylene glycol's main function is to make the curing agent more soluble while distributing it equally in a formulation. Patients are assured that pills, syrups, and creams always contain the exact amount of dosage needed.
It is important that the propylene glycol to be used for health-sensitive applications should have a USP/EP grade. USP stands for the United States Pharmacopeia, which is the country's official standards-setting authority for all prescription and over-the-country drugs, food supplements, and other health care products produced in the United States.
EP meanwhile stands for European Pharmacopeia. It is a semi-autonomous institution of the Council of Europe that also lists a wide range of active substances and excipients used for drug preparation in the aforementioned continent. A chemical substance with either a USP or EP grade means that it has undergone intensive independent testing and review to verify its ingredients, purity, and potency.
Note: * - not permissible for cat food use