Citric Acid: Definition, Properties and Cosmetic Applications

What Is Citric Acid?

Citric Acid is one of the best-known and most widely used fruit acids. It occurs naturally in citrus fruits and is also produced commercially through fermentation, with Aspergillus niger commonly used in its production.

In cosmetic formulation, citric acid is primarily used to adjust and buffer the pH of products. It is particularly useful when a formulation needs to be brought within a specific pH range suitable for the intended product and application.

Citric Acid in Cosmetic Formulation

Citric acid is commonly used to adjust cosmetic formulations toward an acidic pH.

It is considered a relatively mild acid and is practically odourless, making it suitable for a wide range of cosmetic applications when used at appropriate concentrations.

Citric acid can be particularly useful in formulations where pH control is important for product stability, skin compatibility and the performance of other ingredients.

Applications of Citric Acid

Citric acid can be found in a variety of cosmetic and personal-care products, including:

• Skin care products
• Hair rinses
• Bath products
• Bath salts
• Mouthwashes
• Nail care products
• Astringent lotions
• Cleansing and bleaching preparations

A 7% aqueous solution of citric acid has an acidity comparable to lemon juice, although it does not provide vitamin C activity.

Citric Acid and Product pH

Controlling pH is an important part of cosmetic formulation. Citric acid can be added during formulation to achieve the desired pH and, together with an appropriate buffering system, help maintain that pH within the required range.

The required concentration depends on the formulation, its initial pH, the desired final pH and the other ingredients present.

Ingredient Information

INCI Name: Citric Acid
CAS Number: 77-92-9
EINECS Number: 201-069-1