Soap Making Process

There are 2 methods for soap making, the cold process method and the hot process method. In both methods heat might be necessary for saponification.

In the hot process fat and lye are boiled together at around 80–100°C until saponification occurs. The excess liquid will be drained off before spooning the warm soap into a mold or container.

In the cold process fat and lye are combined and it can take up to 6 weeks until the saponification is complete. Cold processed soap is renown for it's harder and long lasting quality.

Soap Making Terms

Curing

The time for the saponification reaction to fully complete itself and the product to settle and mature. In a 'natural' soap the curing process may take 3 weeks or more, and can be done in controlled conditions. If a soap is not fully cured, it may be unstable (fall apart / have uneven colours) and still have some of the original ingredients in an un-reacted form, leading to skin irritation.

Emolients

An ingredient that has a softening effect on the skin: cold cream, lanolin, cocoa butter, powdered oatmeal..

Emulsion

An emulsion is a blend of two or more normally incompatible liquids eg oil and water. A surfactant is often used to help create an emulsion.

Emulsifiers

Emulsifiers are usually used in creams and lotions to achieve a stable mix of what are normally non-mixable materials, such as oil and water.Stops or slows the ingredients separating out

Saponification

Saponification is the main reaction that forms soap when an alkali is reacted with a fat or oil (which are mild acids). This leads to a long molecule that has a water soluble end and a fat soluble end: hence the ability to dissolve greasy compounds into water

Humectant

An ingredient that promotes the retention of water and / or attracts water. These create a moist skin feel.

Hypoallergenic

A claim that the product causes few, if any, allergic reactions. As yet there is no standard for assessing such claims

Milling

Milling soap refers to the re-grinding (chipping) and remixing to ensure all ingredients are uniformly mixed and all air is removed. This leads to a harder soap which will last longer.

Sequestering agents

To prevent metals precipitating as an insoluble

Hydroxide

E.g. EDTA , Citric acid Subsequently reduce the formation of scum and improve foaming properties.

Super-fatted soaps

Addition of extra oil / fatty material to make a 'super-fatted' product which improves skin feel and lathering. eg Lanolin or additional oil (eg coconut oil). A similar result can be achieved by initially adding insufficient alkali, so the saponification reaction is incomplete, leaving free fatty acids.

Surfactants

A Surfactant is a compound that reduces the surface tension of a liquid which improves smearing / spreading / mixing properties. A surfactant may help an emulsion remain stable. Or they may improve the skin "feel" of a product. There are different types of surfactants based on the "charge" at the end:

Anionic

E.g. Sodium sterate sodium Laurel ether sulphate

Cationic

E.g. Benzalkonium chloride

Non-ionics

These are foaming agents

Triple milled soap

See milling