CAS 77-92-9 · Tricarboxylic Acid · GRAS
Citric Acid
Anhydrous & Monohydrate · C₆H₈O₇ · MW 192.12 g/mol
A naturally occurring tricarboxylic acid and the world's most widely used food acidulant. Produced by fermentation of sugars, citric acid is GRAS-listed, biodegradable, and effective across a broad range of industrial, food, pharmaceutical, and cleaning applications. Texas-Chem supplies citric acid in anhydrous, monohydrate, and USP/food grades.
Formula
C₆H₈O₇
Melting Point
156 °C
Solubility
592 g/L at 20 °C
Pack Sizes
Bags · Drums · Super Sacks
Structural Formula
Tricarboxylic acid — three –COOH groups and one central hydroxyl group
Safety & Regulatory
- NFPA Health
- 2 — Moderate hazard
- NFPA Flammability
- 1 — Slight hazard
- NFPA Reactivity
- 0 — Stable
- OSHA PEL
- None established
- ACGIH TLV
- None established
- FDA Status
- GRAS (food/pharma grades)
- DOT Hazard Class
- Not regulated
- Skin/Eye
- Irritant — avoid contact
Food/pharma applications require USP/FCC grade. Always consult the current Safety Data Sheet before handling.
Grades & Packaging
Available Grades
Pack Sizes
Physical & Chemical Properties
| Molecular Formula | C₆H₈O₇ |
| Molecular Weight | 192.12 g/mol |
| CAS Number | 77-92-9 |
| Physical State | White crystalline solid |
| Melting Point | 156 °C (313 °F) — anhydrous |
| Decomposition | >175 °C |
| Density | 1.665 g/cm³ (anhydrous) |
| Solubility in Water | 592 g/L at 20 °C |
| pKa₁ | 3.13 |
| pKa₂ | 4.76 |
| pKa₃ | 6.40 |
| pH (1% solution) | ~2.2 |
Industrial Applications
Food & Beverage Acidulant
The most widely used food acidulant (E330) — provides tartness and pH control in soft drinks, candies, jams, and dairy products. Citric acid accounts for over 70% of global acidulant consumption in food applications.
Cleaning & Descaling
Effective descaling agent for removing calcium carbonate, iron oxide, and other mineral deposits from boilers, heat exchangers, dishwashers, and industrial equipment. Biodegradable and safer than mineral acids for many applications.
Pharmaceuticals
Excipient, pH adjuster, and chelating agent in oral and injectable drug formulations. Used in effervescent tablets (with sodium bicarbonate) and as a preservative in blood collection systems.
Personal Care & Cosmetics
pH adjuster and chelating agent in shampoos, skin creams, and hair dyes. Citric acid sequesters metal ions that would otherwise degrade formulations and discolor products.
Water Treatment
Chelating agent for iron and manganese removal in water treatment. Used to clean reverse osmosis membranes and ion exchange resins, and as a sequestrant in boiler water treatment programs.
Metal Cleaning & Passivation
Mild acid cleaner for removing rust and scale from stainless steel, copper, and aluminum. Used for passivation of stainless steel surfaces in food processing and pharmaceutical equipment.
Why Source Citric Acid from Texas-Chem?
- 35+ years supplying industrial chemicals to Texas manufacturers
- Anhydrous, monohydrate, and USP/food grades available
- Bags, drums, and super sacks for any volume requirement
- Competitive pricing backed by top-tier producer relationships
- Technical support and SDS documentation with every order
- Same-day quotes for standard quantities
Citric Acid vs. Alternatives
Citric acid is a natural, food-safe tricarboxylic acid used across food, pharma, cleaning, and water treatment. Here's how it compares.
| Attribute | Citric Acid | Phosphoric Acid | Sulfamic Acid |
|---|---|---|---|
| Source | Fermentation (natural) | Synthetic (mineral) | Synthetic |
| pKa (first) | 3.13 | 2.15 | 1.0 |
| Food Safety | GRAS — widely used in food | GRAS at low concentrations | Not food-safe |
| Chelating Ability | Excellent — sequesters Ca, Mg, Fe | Good | Minimal |
| Primary Use | Food acidulant, cleaning, pharma | Fertilizers, metal treatment, food | Descaling, cleaning, metal treatment |
Industries We Supply Citric Acid To
Food & Beverage
The most widely used food acidulant — citric acid provides tartness, acts as a preservative, and chelates metal ions in beverages, confections, and canned goods.
Citric Acid supply in Dallas, TXPharmaceutical & Nutraceutical
USP-grade citric acid used as a buffering agent, effervescent base, and chelating agent in tablets, syrups, and dietary supplements.
Citric Acid supply in Houston, TXIndustrial Cleaning & Descaling
Effective descaler for boilers, heat exchangers, and food processing equipment — removes calcium and iron deposits without harsh mineral acids.
Citric Acid supply in San Antonio, TXWater Treatment
Used for pH adjustment, iron sequestration, and membrane cleaning in reverse osmosis and industrial water treatment systems.
Citric Acid supply in Fort Worth, TX