Comprehensive Guide to Food-Grade Propylene Glycol

Common Uses

Propylene glycol’s unique properties contribute to its diverse use in food manufacturing. Most commonly, it functions as a:

• Preservative and antimicrobial agent: Propylene glycol’s hygroscopic properties (attracting and retaining moisture) help prevent the growth of bacteria and mold, thus extending the shelf life of food products. For this reason, it is commonly used in baked goods, candies, and pet food.
• Anticaking agent: Because propylene glycol absorbs moisture, it prevents clumping in powdered food mixtures like drink mixes, dry soups, and cake mixes and keeps such mixtures free-flowing.
• Solvent: As a solvent, propylene glycol dissolves flavorings, colors, and other ingredients and helps ensure a uniform consistency in food products like salad dressings, soft drinks, and beverages.
• Humectant: As a humectant, propylene glycol retains moisture in foods, preventing them from drying out. This is especially important for foods like marshmallows, bakery items, and candies.
• Texturizer: Propylene glycol can modify the texture of foods, thickening liquids, softening baked goods, and adding a smooth mouthfeel to all sorts of delicacies.
• Fat replacer: Propylene glycol can be used as a low-calorie fat replacer in some recipes, creating an impression of creaminess or richness.
• Fermentation agent: In the production of alcoholic beverages like wine and beer, propylene glycol can act as a nutrient to spur the growth of all-important yeast during fermentation.

Propylene glycol is also widely used in pharmaceuticals. Here, it acts as a:

• Solvent: Propylene glycol’s ability to dissolve a wide range of substances makes it a valuable solvent in pharmaceutical formulations. It helps dissolve medications that are insoluble in water, ensuring they are uniformly distributed and readily absorbed by the body. This is especially important for injectable medications, oral liquids, and topical preparations. 
• Carrier: Propylene glycol acts as a carrier for various pharmaceutical ingredients, including actives, flavors, and preservatives. It delivers these components throughout the medication and helps maintain a uniform consistency.
• Humectant: Propylene glycol’s ability to attract and retain moisture prevents some medications from drying out and becoming crumbly or difficult to swallow. This particularly benefits chewable tablets, lozenges, and certain topical creams and ointments.
• Plasticizer: Propylene glycol is used in some soft-gel capsules to make them more flexible and easier to swallow.
• Penetration enhancer: In topical formulations like creams and ointments, propylene glycol can enhance the penetration of active ingredients through the skin.
• Aerosol propellant: Propylene glycol, sometimes combined with other ingredients, can act as a propellant in certain pharmaceutical aerosols, such as inhalers used for asthma treatment.
• Manufacturing aid: Propylene glycol is also used in various stages of pharmaceutical manufacturing processes, including granulation and film coating.

Finally, propylene glycol has also been found to enhance many cosmetic and other personal care products. 

In all of these applications, the propylene glycol used must have achieved food-grade classification to align with regulatory standards. It’s important to note that “food-grade” doesn't always imply the product is intended for oral consumption. Rather, the designation signifies that the propylene glycol meets purity requirements for safe use in any application that may involve human contact.

Regulations and Compliance

Packaging and Handling

Food-grade propylene glycol requires proper packaging in order for it to retain its purity and remain safe for human consumption. Typically available in liquid form, food-grade propylene glycol is commonly packaged in containers such as drums, totes, and bulk tanks. These containers need to be carefully selected and maintained to prevent potential contamination during storage and transportation.

When handling food-grade propylene glycol, strict hygiene protocols must be followed to avoid introducing potentially harmful foreign substances into products. Personnel involved in handling should wear appropriate protective gear, such as gloves and goggles, to minimize the risk of contamination. Additionally, dedicated equipment and storage areas should be utilized to prevent cross-contamination with other substances.

Proper storage conditions for maintaining the quality of food-grade propylene glycol include cool, dry, and well-ventilated areas away from direct sunlight and sources of heat. Containers should be tightly sealed to prevent exposure to moisture and airborne contaminants. Regular inspections should be conducted to ensure the integrity of packaging and identify any signs of damage or leakage.

Furthermore, when transferring propylene glycol from one container to another or dispensing it, appropriate transfer equipment and procedures should be employed to minimize the risk of spills and exposure. Care should be taken to avoid contact with incompatible materials and substances that could compromise the purity of the propylene glycol.

Sourcing Food-Grade Propylene Glycol
with Keller-Heartt

Keller-Heartt Oil’s Truegard line of products offers a comprehensive range of high-quality lubricants, including propylene glycol-based solutions tailored for various industrial applications. Truegard products are meticulously formulated to meet stringent quality standards and deliver exceptional performance in demanding operating conditions—at a fraction of competitor costs.

Among Keller-Heartt’s Truegard offerings, propylene glycol-based lubricants stand out for their versatility and effectiveness in a wide range of applications–both food-grade and otherwise. The non food-grade propylene glycol products are specifically engineered to provide superior lubrication and corrosion protection, making them ideal for use in hydraulic systems, heat transfer applications, and industrial machinery.