What Is Soap Really? Breaking Down the Basics

Soap making can feel overwhelming at first.

The process is technical, especially when you’re just starting.

That’s because soap has a surprisingly complex chemical makeup.

But don’t worry—once you master the basics, the fun begins.

You’ll be free to experiment, get creative, and craft beautiful bars.

What is Soap?

At its core, soap is a product of a saponification chemical reaction. To truly understand soap, let’s delve into the science behind it.

Saponification

Every oil has a unique saponification value, which indicates how much sodium hydroxide (lye) is required to transform that oil into soap.

During saponification, fats, oils, sodium hydroxide, and water react to create glycerin and soap. As you mix these ingredients, they evolve into a thick, uniform texture.

The point at which the soap can be drizzled from a spatula, leaving a trace or pattern on the surface, is known as a “trace.”

This indicates “that the ingredients are evenly dispersed, creating a thick and stable emulsion. It is also the perfect time to pour your mixture into moulds.

Super-Fatting

Super-fatting, sometimes called a “lye discount,” involves leaving a percentage of oil in the final soap bars.

This technique helps to create a milder soap that is kinder to the skin. You can achieve super-fatting in one of two ways:

Reducing the amount of lye by 5%.

Adding extra oils.

Adding the correct percentage of oils can be challenging when starting. You might consider going up to 3% super-fatting for a creamy texture.

After calculating the necessary amount of lye for your homemade soap recipes, deduct the desired super-fat percentage and incorporate the oils in one go.

This method streamlines the process and enhances the final product.

Water

Using the correct type of water is crucial. Spring or distilled water is recommended for soap making.

The amount of water used can vary, but a good rule of thumb is to use 33% of the total weight of oils. This ratio ensures a smooth mix and allows ample time to add essential oils and herbs without feeling rushed.

Pouring

Once your oils have reached trace, they’re thick and incorporate essential oils. At this stage, the mixture should be smooth with no lumps. Spotting watery or oily puddles indicates a poorly mixed solution, which could lead to issues.

When pouring the last bit of soap, be cautious. If it appears too watery or uneven, discard it to avoid contaminating the rest of your batch. If the mixture is unevenly set, use a spatula to spread it evenly in the mould.

Curing

Curing is essential for the soap to harden and evaporate water. This process requires a dry, well-ventilated area shielded from extreme temperatures.

After pouring your mixture into the mould, cover it with a blanket or heavy cardboard and leave it undisturbed for 24 hours.

This insulation allows the soap to heat up and continue saponifying. Once the initial curing period is over, lay the bars on a tray with enough space between them, turning them occasionally to expose both sides thoroughly.

For optimal results, allow the soap to cure for six weeks.

This time is necessary for the soap to dry, harden, and become mild. Using the soap before this curing period is a mistake; it may not cure correctly and could irritate the skin.

Remember not to wait until the soap is rock-hard to cut it into slices; this makes it difficult to cut cleanly. Instead, cut the bars immediately after the insulation period for the best results.

Ready to Dive In?

Soap making is a fascinating blend of art and science.

With a solid understanding of the chemistry involved and the proper techniques, you can create beautiful, fragrant bars tailored to your preferences.

If you’re interested in delving into soap science, check out this article from Lab Muffin. It provides valuable insights into the chemistry behind soap making.