Anhydrous Citric Acid | Cosmetic Ingredients | Aromantic

Anhydrous Citric Acid


What does this mean?

Inci: Citric Acid

Most commonly used to make fizzy bath bombs, anhydrous citric acid can also be used to adjust the pH balance of creams and lotions, and especially shampoos and other hair products.


Citric acid is sold as a white crystalline powder with no aroma. It is a fine grade which makes it easier to work with and makes a much smoother surface bath bomb. Here it is derived from corn (non-GMO) and is COSMOS approved.
It occurs naturally in many fruits and vegetables but is most concentrated in lemons and limes where it can be up to 8% of the fruit content.
Commercially, it is often used as an environmentally benign cleaning agent but in cosmetic production, it is frequently used as an antioxidant.
We regularly add oil-soluble antioxidants to our vegetable oils to slow down oxidation and rancidity. We also add them to creams and lotions but in that sort of product, they're most efficient on the oil-soluble parts of the formulation. Citric Acid is effective as an antioxidant in the water-soluble parts of the formulation.
According to the Cosmetic Ingredient Database (Cosing), the functions of Citric Acid are: Buffering, Chelating, Masking
To view more information, visit the Cosing Database here.


Use in formulations at 0.1% to 4%. It is water-soluble so cannot be used in oil-only formulations. Often used in conjunction with Bicarbonate of Soda to make fizzy bath bombs.
Skin Care
When used at higher concentrations, it has the typical properties of alpha-hydroxy acids and can be used in anti-ageing gels and peels. When used in the lower amounts (0.1%), it can bind and neutralise minerals like magnesium, copper, zinc and calcium (a chelating effect) which will enhance the activity of antioxidants by preventing autoxidation.
Hair Care
Detergents are very alkaline and if not adjusted to a more skin friendly pH, can feel very tight and itchy on the scalp. For something like a hair care product, we want a pH around the pH of our hair, which is 5.6 to 6.2. The same applies to shower gels. Add Citric Acid in very small amounts, after all other ingredients and essential oils have been added to move the pH to a more skin-friendly level.
Works well in hair conditioners and hair packs as well but do not use too much as it can change the colour of your hair (not in a good way!).


Be careful not to take the pH of a product below 3.5 as that is a peeling level acidity on the skin. Citric Acid will sting if it gets into cuts or scratches on your skin and will also be very irritating to the eyes. This is relevant if you are making and moulding bath bombs or if working with children who may rub their eyes.


Click on the links below to be directed to great recipes featuring Citric Acid:


Citric Acid was first isolated by the Swedish chemist Carl Wilhelm who crystallised it from lemon juice. Mass production started in 1890 with the Italian fruit industry supplying the raw materials. By 1893, it was found that a form of penicillin mould could also produce citric acid but the natural fruit supply was abundant and therefore cheaper. However, the first World War interrupted the supply chain and so a new way was needed to keep up the production. By 1917, it was found that certain strains of the Aspergillus Niger mould could also produce Citric Acid very efficiently and this is still the maIn manufacturing process used today.