TRIETHYL CITRATE

Introduction

Triethyl citrate (TEC) is the triethyl ester of citric acid. It is a colorless, odorless, and practically tasteless oily liquid. As a food additive, it is designated as E1505 and functions primarily as a food additive, emulsifier and solvent. It is also used as a whipping aid to stabilize foams, especially for egg white.

Outside of direct food applications, TEC is a valuable indirect food additive. It is widely used as a plasticizer for polymers and as a solvent in coatings for food packaging and pharmaceuticals. Its excellent safety profile and biodegradability make it a preferred alternative to phthalate plasticizers.

CAS Number

77-93-0

Synonyms

• Citric acid triethyl ester
• Ethyl citrate
• E1505
• TEC
• Triethyl ester of citric acid

Topic Headings

1. Primary Food Applications (list form)

• Whipping aid — Added to liquid egg whites or whipping creams to improve foam formation and stabilization, increasing volume and texture.
• Solvent for flavors — Used as a diluent and carrier for oil-soluble flavors in beverages, baked goods, and dairy products.
• Plasticizer in food contact materials — Used in food-grade adhesives, printing inks, and coatings for packaging where non-toxicity is paramount.
• Firming agent — Used in some fruit preparations and jellies to help maintain texture.
• Emulsifier — Helps to stabilize oil-in-water emulsions in certain food systems.

2. Mechanism of Action as a Whipping Aid (paragraph form)

In egg white whipping, the protein albumin must unfold and form a stable network around air bubbles. Triethyl citrate acts as a co-surfactant. It reduces the surface tension at the air-water interface, allowing the egg white proteins to adsorb and unfold more readily. This leads to faster incorporation of air, a finer and more uniform bubble structure, and greater foam stability. The result is a meringue or angel food cake with significantly higher volume and a more delicate, fine-grained crumb. It also reduces the risk of over-whipping.

3. Physical and chemical properties (list form)

• Appearance — Colorless, oily liquid.
• Odor — Odorless.
• Molecular weight — 276.28 g/mol.
• Boiling point — 294°C.
• Viscosity — Low to moderate (approx. 32-35 cP at 25°C).
• Solubility — Slightly soluble in water (approx. 6.5 g/100 mL), miscible with organic solvents.
• Boiling point — Approximately 294°C.
• Melting point — Approx. -46°C.

4. Safety and Regulatory Status (paragraph form)

Triethyl citrate is an exceptionally safe food additive. It is metabolized in the body into citric acid (a normal component of the Krebs cycle) and ethanol (which is further metabolized). The FDA lists it as a GRAS substance for use as a flavoring agent, adjuvant, and as a plasticizer in food contact materials (21 CFR 184.1911). In the EU, it is designated as E1505 and is permitted for use in various foods, including egg white preparations and as a flavor carrier. JECFA has established an ADI of "not specified." Due to its low toxicity, it is a common ingredient in pharmaceutical coatings to mask bitter tastes.