Triethyl Citrate  is a chemical compound, diester of citrate (citric acid or α and β-hydroxytricarboxylic acid) alkyl with ethyl alcohol.

The industrial production of citric acid takes place by mycological fermentation of raw sugar from Aspergillus niger and subsequent crystallisation with alkaline solutions.

It appears as oily liquid soluble in water and virtually odorless.

What it is used for and where

Food 

Ingredient on the European food additives list as E1505, thickener, stabiliser.

Stabilizer of soybean oil and various seasoning oils and margarine. Flavor enhancer to improve the taste in soft drinks, desserts, cooked foods. Also can be used as a solvent for flavoring berries. Leavening agent to improve foaming properties in baked goods.

Safety

With regard to safety, Triethyl Citrate (in the form of Acetyl Triethyl Citrate) is considered relatively safe based on the toxicological data published to date, and this pharmacokinetics study demonstrated that Acetyl Triethyl Citrate rapidly disappeared from plasma. Metabolite profiling data indicated that Acetyl Triethyl Citrate was extensively metabolized and excreted primarily as metabolites rather than the parent form. This is the first report demonstrating a bioanalytical method for the determination of Acetyl Triethyl Citrate in biological samples and its pharmacokinetic properties (1).

Pharmaceutical

In tablets, it is a non-toxic hydrophilic plasticizer that can be incorporated into the film coating of pressure-coated tablets consisting of hydroxypropyl methyl cellulose acetate succinate or enteric polymer films consisting of polymethyl methacrylate. Triethyl Citrate performs the function of reducing damage during the compression process.

Cosmetics

Chelating agent, a chemical compound that reacts with metal ions to form a stable, water-soluble complex. Used as an antioxidant, solvent, deodorant, odor inhibitor and plasticizer.  Skin care products plasticized with Triethyl Citrate have good resistance to oil, light and mildew.

Medical

It is used in protein films composed of sunflower protein or whey protein or for buccal and sublingual films or particulate systems.

A study on hidradenitis suppurativa, a chronic disease of the terminal follicular epithelium in areas bearing apocrine glands, demonstrated the efficacy of a lotion composed of Triethyl citrate, ethyl-linoleate, and g-peptide-10. This composition had already demonstrated efficacy in the treatment of acne (2).

Plastic 

Plasticizer for thermoplastic resins such as cellulose resin, vinyl resin and soft toys. As plasticizer for adhesives and sealants, it can replace dibutyl phthalate, diisobutyl phthalate, dimethyl phthalate, diethyl phthalate, etc.

General features for liquid Triethyl Citrate

• Boiling point  235 °C/150 mmHg (lit.)
• Melting point  -55 °C
• density  1.14 g/mL at 25 °C (lit.)
• vapor density  9.7 (vs air)
• vapor pressure  1 mm Hg ( 107 °C)
• FEMA  3083 | TRIETHYL CITRATE
• refractive index  n20/D 1.442(lit.)
• Fp  >230 °F
• storage temp.  -20°C

Triethyl Citrate studies

• Molecular Formula: C₁₂H₂₀O₇
• Linear Formula: HOC(COOC₂H₅)(CH₂COOC₂H₅)₂
• Molecular Weight:  276.28
• CAS: 77-93-0
• UNII 8Z96QXD6UM
• EC Number:   201-070-7
• DSSTox Substance ID: DTXSID0040701
• MDL number  MFCD00009201
• PubChem Substance ID 329823171
• FEMA   3083
• Bellstein: 1801199
• NACRES  NA.24

Synonyms: 

• Ethyl citrate
• Citric acid, triethyl ester

References__________________________________________________________________

(1) Kim H, Ji YS, Rehman SU, Choi MS, Gye MC, Yoo HH. Pharmacokinetics and Metabolism of Acetyl Triethyl Citrate, a Water-Soluble Plasticizer for Pharmaceutical Polymers in Rats. Pharmaceutics. 2019 Apr 3;11(4):162. doi: 10.3390/pharmaceutics11040162.

(2) Skroza N, Mambrin A, Tolino E, Marchesiello A, Proietti I, Bernardini N, Potenza C. Efficacy and tolerability of a lotion containing triethyl citrate, ethyl linoleate, and GT peptide-10 in the adjuvant treatment of hidradenitis suppurativa: Real-life data. Dermatol Ther. 2018 Jul;31(4):e12599. doi: 10.1111/dth.12599.