TRIACETIN (E1518)

Introduction

Triacetin, designated as E1518, is the triester of glycerol and acetic acid. It is a colorless, oily liquid with a slightly bitter taste and a faint fatty odor. As a food additive, it serves several important functions, primarily as a humectant (moisture retainer), a solvent for flavorings, and a plasticizer.

Its most significant role in food is in the formulation of chewing gum base, where it acts as a plasticizer to soften the gum and ensure a smooth, pliable texture. It is also a valuable carrier and solvent for flavor concentrates, helping to disperse them evenly in baked goods, beverages, and confectionery. Beyond food, Triacetin is used in pharmaceuticals as a solvent and as a plasticizer for coatings on pills and capsules.

CAS Number

102-76-1

Synonyms

• Glyceryl triacetate
• Glycerin triacetate
• 1,2,3-Triacetoxypropane
• E1518
• Enzactin

Topic Headings

1. Primary Food Applications (list form)

• Humectant in chewing gum — Retains moisture in gum base, preventing it from becoming hard and brittle over time.
• Plasticizer in chewing gum — Softens the gum base polymer, giving it a pliable, cohesive texture.
• Flavor solvent — As a high-quality solvent, it safely and effectively dilutes and carries oil-soluble flavors for baked goods, confectionery, and other foods.
• Film former — Forms a thin, protective film on foods in certain glazing applications.
• Anti-foaming agent — Used in very small quantities to control foam in some food processing operations.

2. Mechanism of Action as a Plasticizer and Humectant (paragraph form)

In chewing gum, the gum base is a complex mixture of elastomers and resins. On its own, this base is too hard and rigid for a pleasant chewing experience. Triacetin acts as a plasticizer by penetrating the polymer network and reducing the intermolecular forces between the polymer chains. This increases the free volume within the material, making it softer and more flexible. Additionally, Triacetin is hygroscopic, meaning it readily attracts and holds onto water. This humectant property ensures the gum retains its moisture content, preventing it from drying out, becoming brittle, and losing its desirable texture over time.

3. Physical and chemical properties (list form)

• Appearance — Colorless, oily liquid.
• Odor — Faint, fatty odor.
• Molecular weight — 218.21 g/mol.
• Boiling point — 258-260°C.
• Viscosity — Moderate, about 15-20 cP at 25°C.
• Solubility — Slightly soluble in water (approx. 6 g/100 mL) but miscible with many organic solvents.
• Density — 1.156 g/cm³ at 25°C.

4. Safety and Regulatory Status (paragraph form)

Triacetin is fully approved for use as a direct food additive worldwide. It is considered to be very safe and has a long history of use. The FDA lists it as a GRAS substance for use as a flavoring agent, adjuvant, and as a plasticizer in food contact materials. In the EU, it is designated as E1518 and is authorized for use in various food categories, including chewing gum and flavored drinks. JECFA has established an Acceptable Daily Intake (ADI) of "not specified" for triacetin, which is the safest category, indicating that no toxicological concerns exist at current usage levels.