Lactic Acid
High purity organic acid
Overview
Lactic Acid (CAS No: 50-21-5), also known as 2-hydroxypropanoic acid, is a colorless to slightly yellow organic acid. It occurs naturally in dairy products as a result of fermentation and is produced in the human body during muscle activity.
Lactic acid is an alpha-hydroxy acid (AHA) widely used in both food and industrial applications. It is completely soluble in water and has a slightly sour taste. Commercially, it is available as L-(+)-lactic acid, D-(-)-lactic acid, or racemic DL-lactic acid.
Applications
Lactic Acid has a wide range of industrial and commercial applications:
Food and Beverage Industry
Used as an acidity regulator, preservative, and flavoring agent in cheese, yogurt, meat products, and beverages.
Cosmetics and Personal Care
Used in skincare products as a pH regulator, moisturizer, and peeling agent.
Pharmaceutical Products
Used in drug formulations as a pH regulator, solvent, and active ingredient.
Bioplastic Production
Used as a raw material in the production of polylactic acid (PLA).
Leather Industry
Used in leather tanning processes and pH adjustment.
Cleaning Products
Used in cleaning products due to its descaling and disinfectant properties.
Technical Specifications
| Property | Value | Unit | Test Method |
|---|---|---|---|
| Chemical Formula | C₃H₆O₃ | - | - |
| CAS Number | 50-21-5 | - | - |
| Molecular Weight | 90.08 | g/mol | - |
| Appearance | Colorless to slightly yellow syrup | - | Visual |
| Odor | Slight characteristic | - | - |
| Density (25°C) | 1.206 | g/cm³ | ASTM D4052 |
| Melting Point | 16.8 | °C | ASTM D1015 |
| Boiling Point | 122 (15 mmHg) | °C | ASTM D1078 |
| Flash Point | 110 | °C | ASTM D93 |
| Vapor Pressure (25°C) | <0.1 | mmHg | ASTM D2879 |
| Water Solubility (20°C) | Completely miscible | - | ASTM E1148 |
| pH Value (0.1M sol.) | 2.4 | - | ASTM E70 |
| Purity | ≥80-90% | % | ASTM E611 |
| Lactic Acid Content | ≥88% | % | HPLC |
| Chloride Content | ≤50 | ppm | ASTM D512 |
| Sulfate Content | ≤100 | ppm | ASTM D516 |
Safety Information
Hazard Symbols and Statements
Irritant Eye Irritation
Personal Protective Equipment (PPE)
- Acid-resistant gloves (nitrile or neoprene)
- Chemical goggles or face shield
- Lab coat or protective clothing
- Dust mask (if in powder form)
Storage Conditions
- Store in a cool, dry, and well-ventilated area
- Keep in original packaging, tightly closed
- Storage temperature: 15-25°C
- Keep away from bases and oxidizing agents
- Do not store in metal containers
Fire Fighting
- Suitable extinguishers: Water spray, dry chemical, CO₂, foam
- Carbon dioxide and carbon monoxide may be released during fire
- Firefighting personnel should use appropriate respiratory protection
Handling and Storage
Transportation
- Ensure containers are tightly closed
- Transport separately from oxidizing agents and bases
- Protect from temperature fluctuations during transport
- Keep neutralizing material available for spills
- Provide adequate ventilation in transport vehicles
Storage
- Store in polyethylene, glass, or stainless steel containers
- Display appropriate signs in storage areas
- Keep acid neutralizing material in storage areas
- Protect from direct sunlight
- Storage shelves should be made of corrosion-resistant material
Spill Response Measures
- Evacuate exposed personnel from the area
- Use appropriate personal protective equipment
- Contain the spill with sand, sodium bicarbonate or other neutralizing materials
- Wash the area with plenty of water
- Collect the spill with absorbent materials
Regulatory Information
GHS Classification
- Skin Irritation Category 2
- Serious Eye Damage Category 1
- Respiratory Tract Irritation Category 3
Important Regulations
- FDA: 21 CFR 184.1061 - GRAS status
- EFSA: Approved as food additive E270
- REACH: Registered
- USP/FCC: Meets pharmaceutical and food quality standards
Food Compliance Certificates
- FCC (Food Chemicals Codex) compliant
- Kosher certified (optional)
- Halal certified (optional)
- GMO-free
- Vegetarian/Vegan compliant
Environmental Information
Environmental Impact
Lactic acid shows low toxicity in aquatic environments. It may be harmful to aquatic life at high concentrations. It easily degrades in soil and water and is completely biodegradable.
Biodegradation
- Air: Degrades through photochemical reactions
- Water: Rapidly degrades through microbial activity (>90% within 28 days)
- Soil: Rapidly degrades through microbial activity
Waste Management
- Not classified as hazardous waste
- Can be disposed of by neutralization at licensed waste disposal facilities
- Should not be discharged into sewers or surface waters
- Dispose of in accordance with local regulations
Frequently Asked Questions
Where is lactic acid found naturally?
Lactic acid occurs naturally in milk and dairy products (especially yogurt and cheese) as a result of fermentation by lactic acid bacteria. It is also produced in human muscle cells during intense exercise.
What is the purpose of lactic acid in foods?
In foods, it is used as an acidity regulator, preservative, flavoring agent, and leavening agent. In cheese production, it causes milk to coagulate, and in meat products, it prevents microbial growth.
What is the role of lactic acid in skincare?
In skincare products, it is used as a pH regulator, moisturizer, and peeling agent. It helps remove dead skin cells, improves skin texture, and increases moisture retention capacity.
What are the differences between lactic acid concentrations?
In industry, it is typically used as an 80-90% aqueous solution. In food applications, 50-80% concentrations are preferred; in cosmetics, 5-15%; and in peeling products, 5-30% concentrations are used.
What should I do if lactic acid comes into contact with skin?
Remove contaminated clothing immediately and wash skin with plenty of water and soap for at least 15 minutes. If burning or irritation continues, seek medical attention. In case of eye contact, rinse eyes with plenty of water for at least 15 minutes and seek immediate medical attention.