The makers of Shout keep the exact ingredient list of their stain removing products a guarded secret. The manufactures of Shout do disclose that the main ingredients in their stain-fighting products are surfactants and enzymes, and it is stated that they do not contain phosphorous or bleach.

Shout sells several different stain-fighting versions of its product. Each product is designed to fight different types of stains. The different formulas most likely utilize various types of surfactants and enzymes that work on different types of stains. The undisclosed extra ingredients in the formulas probably enhance the stain-fighting abilities of the main ingredients. It adds a desirable scent to the products.

Surfactants are the main cleaning agents in most cleaning products. They can be made from natural sources or synthetic sources. Natural surfactants are made out of vegetable or animal fats. Synthetic surfactants are made out of petrochemicals. The molecules in surfactants attract to dirt and oils. They release their bond to the dirtied material. Different surfactants attract to and release different forms of dirt and oils.

Enzymes are protein molecules. When added to cleaning products, they increase the speed of stain removal. The enzymes attack and break down dirt and oils. There are different types of enzymes, each effective on different types of stains. Cleaning and stain fighting product makers choose enzymes to include in their product formulations, based on the stains they want their products to remove. Shout must formulate its products to include ingredients that are harmless to the enzymes. Bleach would destroy the enzyme molecules, making them ineffective.

Shout uses surfactants and enzymes as the main ingredients in its formulas to remove stains. The main ingredients are known stain removers that are commonly used in other brands of cleaning products.