Sodium Lactate

INCI Name: Sodium Lactate

Chemical Formula: C₃H₅NaO₃

CAS Number: 72-17-3

EINECS Number: 200-772-0

Synonyms: Lactic acid sodium salt, sodium 2-hydroxypropanoate

Sodium Lactate is the sodium salt of lactic acid, a naturally occurring alpha-hydroxy acid (AHA) produced through the fermentation of sugars such as corn or beets. It functions as a humectant, moisturizer, and pH regulator in cosmetic and personal care formulations. Known for its high water-binding capacity, Sodium Lactate helps maintain skin hydration and improves product stability. It is also used in soap making to produce harder, longer-lasting bars.

Physical and Chemical Properties

Usage Guidelines

Typical Usage Rate:

• Skin care: 1–3% for humectant/moisturizing effects

• Soaps: 1–3% of total batch weight for hardness and longevity

• pH Adjustment: As needed to increase alkalinity slightly

Phase: Water phase (water-soluble; can be cold or hot processed)

Processing:

• Add directly to the water phase or cool-down phase in emulsions

• In cold process soap, add to cooled lye water to prevent overheating

pH Stability: Stable in formulations between pH 3–12

Source and Production

Produced by fermenting plant-based sugars (commonly from corn or beets) into lactic acid via bacterial cultures, then neutralizing with sodium hydroxide to form sodium lactate.

Functions and Applications

Primary Functions:

• Humectant – Attracts and retains moisture in the skin

• Moisturizer – Enhances skin softness and hydration levels

• pH Regulator – Adjusts pH in aqueous formulations

• Soap Hardener – Produces a harder, longer-lasting bar in CP soap

Applications:

• Creams, lotions, and serums

• Body washes and facial cleansers

• Shampoos and conditioners

• Bar soaps and syndet bars

• After-sun and hydrating sprays