How Does Soap Work?
How does soap work?
Soap works as an extremely effective cleanser. Not only does it cleanse by removing dirt and oil from the skins surface, it also sanitises by destroying microbes, bacteria and viruses. The majority of us use soap to cleanse our hands, face or body at least once per day. Research shows that in 2020, an estimated 3.7 million people in the UK used a bar of soap ten times a day or more.
Such a common household object is often used without a second thought, but why do we wash with soap? We are all aware that soap works to remove dirt and grease in order to produce a cleaner, more sanitised result – but how? How does soap work and what is the science behind it? Read on to discover how soap works.
What is soap?
‘Soap’ is defined as fat or oil combined with an alkali. The oil is derived from an animal or plant, whereas the alkali is a chemical known as lye. The lye used in the production of bar soap is sodium hydroxide. Potassium hydroxide is required for liquid soap.
Soap is produced by combining and then heating oil and lye. This chemical reaction is known as saponification. With soap bar production, the formula is then pressed into moulds.
The History of Soap
Records show that soap was produced as early as 2800BC by the Ancient Babylonians, but soap became particularly popular during the Victorian era, when mass production became feasible following the industrial revolution. This combined with a growing understanding of sanitary practises and advertising to encourage bathing with soap, ensured that the humble soap bar fast became an essential household object.
The Benefits of Washing with Soap

Soap Deals with Grease
When you wash with soap and water, the soap molecules attach to fat and grease molecules. This is why a good lather is important. The grease is then rinsed away alongside the soap lather. See the Science Behind Soap below.

Scented Soap
Fragrance is often added to the soap formula during the manufacturing process. When it comes to soap fragrance, the choice is endless! Explore The English Soap Company Soap fragrances here.

Soap Nourishes the Skin
Added ingredients such as shea butter and vitamin E ensure washing with soap nourishes the skin and locks in moisture. Other natural ingredients such as sulphur, aloe vera and tea tree oil can reduce irritation and skin complaints.
The Science Behind Soap

Soap is a Surfactant
Soap works as a natural surfactant. Surfactants are substances that reduce the surface tension of a liquid in which they are dissolved. Soap reduces the surface tension of water by interacting with the water molecules, making them less likely to stick together and more likely to interact with oil and grease.

Soap is both Hydrophillic & Hydrophobic
Soap can attach to both fat and water molecules.The soap molecule has two different ends, one that is hydrophobic (repellent to water) that binds with grease and oil, while the hydrophilic (water-attracting) end binds with water molecules, so it can be rinsed away.

Soap Surrounds Fat Molecules
When greasy dirt or oil is mixed with soapy water, the soap molecules arrange themselves into tiny clusters called micelles. The water-loving (hydrophilic) part of the soap molecules sticks to the water and points outwards, forming the outer surface of the micelle. The oil-loving (hydrophobic) parts stick to the oil and trap oil in the centre. The soap molecules arrange themselves to become a barrier, trapping the oil in the centre. As the soapy water is rinsed away the greasy dirt goes along with it.

Soap Washes Everything
When you wash with soap and water the soap molecules grab on to the fat molecules and pulls them off the skin into the rinse water. When your rinse the skin the fat and germs are removed from the skin. Therefore, the main reason why soap works to cleanse and sanitise is it literally washes everything off the skin.
How to Wash Your Hands with Soap
Keeping hands clean is one of the most important steps we can take to avoid illness and spreading germs to others. Follow the World Health Organisation’s recommended method to ensure you wash your hands in the most effective and sanitised way. For more information about thorough hand washing methods, click here.

STEP ONE:
Wet Your Hands
Clean, running, hot water is best for cleansing with soap.
Why? Standing water may be contaminated, if possible, use water flowing from a tap. High temperature water softens and melts fats and oils, allowing them to attach more readily to the soap molecules. In turn, the hot water helps to soften the soap allowing it to lather and get to work more easily.

STEP TWO:
Lather your soap bar
Wet the soap bar, rubbing to create a foam and begin to lather your hands, ensuring you rub the front and back of your hands, fingers and thumbs and under nails. Don’t forget those wrists! Continue for 30 seconds.
Why? Lathering activates the soap, allowing the soap molecules to attach more readily to dirt and microbes. Scrubbing hands creates friction, which physically helps lift dirt, grease and microbes from skin. Research suggests that washing hands for about 15-30 seconds removes more germs from hands than washing for shorter periods.

STEP THREE:
Rinse and dry your hands
Rinse in clean running water, ensuring you wash away all the soap lather. Dry your hands thoroughly, preferably with a dry paper towel.
Why? By washing away the soap lather, all the dirt, germs and microbes attached to the soap molecules will be rinsed away with it.
Soap bar or liquid soap?
In January 2021, we introduced our very first liquid soap, launching the Kew Gardens Hand Washes. Our perfected liquid soap formula is now available in other collections including our beloved Anniversary Collection, Bath and Body and the all new Take Care Collection expansion.

The English Soap Company Soap
The English Soap Company soap bars and liquid soaps are created using a formula perfected by our founder to create the perfect soap bar: long-lasting, boldly fragranced, and with a sumptuous lather. They are made with a special combination of vegetable oils and are vegan and eco-friendly. See below our recommended soaps for cleansing.