Soap and surfactants: how cleaning works

In short: Soap and detergents contain surfactants, molecules with a water-loving and a fat-loving end. They loosen grease and dirt from skin and textiles and rinse them away with water.

In more detail: Fat and water do not mix; surfactants mediate between the two.

In detail

• Structure: Water-loving (hydrophilic) head and fat-loving (lipophilic) tail.
• Micelles: Surfactants envelop fat droplets and let them float in water.
• Soap: Alkaline, made of fats and lye; “saponification”.
• Detergent: Additionally contains enzymes, bleach and softeners.
• Water temperature: Heat dissolves fat better (waerme-und-temperatur).
• Handwashing: 20 to 30 seconds with soap also removes germs (haende-waschen-und-hygiene).
• Environment: Mind the dosage, prefer biodegradable surfactants.
• pH value: Soap is basic, skin care often slightly acidic (ph-wert-saeuren-und-laugen).