Citric acid
Aqueous and Ethanolic Solubility: Exhibits notable solubility in both aqueous and ethanolic systems, supporting its utility as an acidulant, preservative, and stabilizing agent in food, pharmaceutical, and cosmetic formulations.
Industrial Implementation Spectrum: Demonstrates extensive utilization across food processing, pharmaceutical manufacturing, and cleaning product sectors, functioning as an effective preservative, pH modifier, flavor enhancer, and chelating agent.
Hygroscopicity and Storage Stability: Displays hygroscopic characteristics under ambient conditions while maintaining chemical integrity during storage at 2-8°C, with defined phase transition temperatures including melting point (153-159°C) and decomposition temperature (248°C).
Acidic Properties and Handling Considerations: Possesses significant acidity suitable for diverse applications, though requires careful handling due to potential localized irritation, with established safety profiles for pharmaceutical and food-grade applications.
Anhydrous citric acid constitutes a naturally occurring compound that functions as an intermediate metabolite in both plant and animal physiological pathways. It represents one of the most extensively utilized organic acids across food, pharmaceutical, and chemical manufacturing sectors. This material typically appears as colorless transparent or translucent crystalline structures, with available forms including granular particulates and fine powder preparations.
Melting point | 153-159 °C (lit.) |
Boiling point | 248.08°C (rough estimate) |
density | 1.67 g/cm3 at 20 °C |
bulk density | 560kg/m3 |
vapor density | 7.26 (vs air) |
vapor pressure | <0.1 hPa (20 °C) |
refractive index | 1.493~1.509 |
FEMA | 2306 | CITRIC ACID |
Fp | 100 °C |
storage temp. | 2-8°C |
solubility | Citric acid also dissolves in absolute (anhydrous) ethanol (76 parts of citric acid per 100 parts of ethanol) at 15 °C. |
form | grit |
pka | 3.14(at 20℃) |
color | White |
PH | 3.24(1 mM solution);2.62(10 mM solution);2.08(100 mM solution); |
Odor | Odorless |
biological source | synthetic |
Odor Type | odorless |
explosive limit | 8%, 65°F |
soluble in Water (1174g/L at 10°C, 1809g/L at 30°C, 3825g/L at 80°C). | |
Sensitive | Hygroscopic |
λmax | λ: 260 nm Amax: 0.20 |
Merck | 14,2326 |
JECFA Numbr | 218 |
BRN | 782061 |
Stability: | Stable. Incompatible with bases, strong oxidizing agents, reducing agents, metal nitrates. |
InChIKey | KRKNYBCHXYNGOX-UHFFFAOYSA-N |
LogP | -1.64 |
CAS DataBase Reference | 77-92-9(CAS DataBase Reference) |
NIST Chemisty Reference | 1,2,3-Propanetricarboxylic acid, 2-hydroxy-(77-92-9) |
EPA Substance Registry System | Citric acid (77-92-9) |
Safety Information
Hazard Codes | Xi,C,T |
Risk Statements | 41-36/37/38-36/38-37/38-34-36-35-61-60 |
Safety Statements | 26-39-37/39-24/25-36/37/39-45-36-53 |
RIDADR | UN 1789 8/PG 3 |
WGK Germany | 1 |
RTECS | GE7350000 |
F | 9 |
TSCA | Yes |
HS Code | 2918 14 00 |
Hazardous Substances Data | 77-92-9(Hazardous Substances Data) |
Toxicity | LD50 in mice, rats (mmol/kg): 5.0, 4.6 i.p. (Gruber, Halbeisen) |
The substance is characterized by complete absence of odor and delivers a characteristically sharp acidic taste that evolves into subtle astringency. When exposed to warm, dry air, it undergoes gradual moisture loss (weathering), while demonstrating slight deliquescent behavior under humid environmental conditions.
