Cocoyl soy polypeptide or Potassium cocoyl hydrolyzed soy protein (INCI) is a functional lipoprotein surfactant, lipoamino acid, a protein of vegetable origin extracted by an industrial process of condensation of coconut oil fatty acids, potassium salt and soy protein hydrolysate.

The name describes the structure of the molecule:

• Potassium indicates the presence of potassium ions (K+) in the compound.
• Cocoyl indicates that the molecule is derived from fatty acids found in coconut oil (hence "coco") and that it is an amide (hence "-oyl").
• Hydrolysed soy protein indicates that the molecule contains hydrolysed soy protein, i.e. soy protein that has been broken down into smaller components.

The synthesis process takes place in different steps:

• Preparation of coconut oil and soy protein. Coconut oil, which contains a high percentage of fatty acids, is extracted from the flesh of the coconut. Soy protein is extracted from soybeans and then hydrolysed, i.e. broken down into smaller components, using water and enzymes or acids.
• Reaction for the formation of hydrolysed soy protein with cocoyl.  Fatty acids from coconut oil react with the hydrolysed soy protein. This reaction results in the formation of an amide bond between the fatty acid and the protein, forming the hydrolysed cocoyl soy protein.
• Neutralisation with potassium hydroxide. The cocoyl-hydrolysed soy protein is then neutralised with a base, such as potassium hydroxide (KOH), to form the potassium salt, cocoyl hydrolysed soy protein.

What it is for and where

Cosmetics

Surfactant - Cleansing agent. Cosmetic products used to cleanse the skin utilise the surface-active action that produces a lowering of the surface tension of the stratum corneum, facilitating the removal of dirt and impurities. 

Skin conditioning agent. It is the mainstay of topical skin treatment as it has the function of restoring, increasing or improving skin tolerance to external factors, including melanocyte tolerance. The most important function of the conditioning agent is to prevent skin dehydration, but the subject is rather complex and involves emollients and humectants that can be added in the formulation.

Hair conditioning agent. A significant number of ingredients with specific and targeted purposes may co-exist in hair shampoo formulations: cleansers, conditioners, thickeners, matting agents, sequestering agents, fragrances, preservatives, special additives. However, the indispensable ingredients are the cleansers and conditioners as they are necessary and sufficient for hair cleansing and manageability. The others act as commercial and non-essential auxiliaries such as: appearance, fragrance, colouring, etc. Hair conditioning agents have the task of increasing shine, manageability and volume, and reducing static electricity, especially after treatments such as colouring, ironing, waving, drying and brushing. They are, in practice, dispersants that may contain cationic surfactants, thickeners, emollients, polymers. The typology of hair conditioning agents includes: intensive conditioners, instant conditioners, thickening conditioners, drying conditioners. They can perform their task generally accompanied by other different ingredients.

The manufacturers of this naturally derived chemical compound claim that it is a product that reduces the irritation that traditional surfactants can cause and is therefore also suitable for intimate hygiene.

In the technical data sheet however, we find the following as preservatives : 

• Phenoxyethanol  <= 1,0%
• Sodium benzoate <= 0,5%

Phenoxyethanol must not come into contact with the eyes or the epidermal areas surrounding the eyes.

CAS Number: 169590-92-5

COSING REF No:    59111

Commercial applications

Hair Conditioning Agent. Used in conditioners and hair treatments to detangle and condition the hair, making it soft and manageable.

Thickening Agent. It is used to increase the viscosity of cosmetic products, such as shampoos and conditioners.

Moisturizing Agent. Used in skin care products to help keep the skin moisturized, leaving it soft and smooth.

Hair Care Protein. Provides nourishment to the hair, improving its structure and appearance.

Please note that Potassium Cocoyl Hydrolyzed Soy Protein is generally considered to be a safe and effective ingredient in personal care products, but it is always important to check the regulations in your area.

References_____________________________________________________________________

Bährle-Rapp, M., & Bährle-Rapp, M. (2007). Potassium Cocoyl Hydrolyzed Soy Protein. Springer Lexikon Kosmetik und Körperpflege, 443-443.