Sodium Metabisulfite

Sodium Metabisulfite is a white crystalline powder commonly used as an antioxidant and preservative in cosmetic formulations. It helps prevent product discoloration, rancidity, and degradation caused by oxidation. Because of its strong reducing properties, it is often added in small amounts to extend shelf life and maintain product quality.

INCI: Sodium Metabisulfite

Functions:

• Antioxidant (protects formulas from oxidation)
• Preservative and stabilizer
• Reduces discoloration in cosmetic products
• Helps maintain freshness of sensitive actives

Solubility:

Highly soluble in water

Slight solubility in alcohol

Appearance:

White powder

Usage Rate:

Typically 0.1–1% in cosmetic formulations

Always use at recommended levels to avoid irritation

pH Stability Range:

Best performance in acidic to neutral pH systems (pH 3–6)

Compatibility:

Works well with water-based systems

Incompatible with strong oxidizing agents

Applications:

• Creams, lotions, and serums (as antioxidant)
• Hair products (especially color stabilizers)
• Some cleansers and water-based formulations
• Often used in food and pharmaceuticals (but here: cosmetic grade only)