How To Make Bar Soap

Soap bars

Everyone wonders how to make bar soap. The advantages of homemade bar soap are natural ingredients and fragrances that are better for your skin and health.

You can make it with the ingredients that you choose and the fragrances that you like.Β  Plus, a homemade bar soap will last you for months.

What are the ingredients of handmade bar soap

To make bar soap completely from scratch you will need:

  • Lye also known as sodium hydroxide
  • Oil
  • Water

Most soap also has other ingredients added, to provide benefits to the soap, to color and scent it.

What is Lye?

  • Lye is a chemical compound known as sodium hydroxide.
  • This component is used in many different ways, such as: food preparation, biodiesel production, water treatment, and of course in making soaps and detergents.
  • Lye is highly corrosive and known as a β€œcaustic soda”.
  • It creates a strong alkaline solution when it is dissolved in water.
  • Today, lye is commonly manufactured as flakes, pellets, or powder.
Lye sodium hydroxide

When oil and lye are combined and heated, the result is soap. This chemical reaction is called saponification.

Without lye, saponification isn’t possible, so lye is necessary to create soap

All REAL soap is made with lye (sodium hydroxide mixed with liquid). Any skin or hair cleansing product made without sodium hydroxide is not soap, it is detergent.

Soap” bars are made with lye even though the words “sodium hydroxide” or “lye” do not appear on the labels.Β 

Ingridients you didn’t know soaps cobtains

If your bar soap contains ingredients from the lust below, then your soap does contain lye.

  • saponified oils:Β oils and butters are mixed with sodium hydroxide and a liquid (usually water).
  • sodium cocoate:Β the generic name for the mixture of coconut oil with sodium hydroxide (lye).
  • Another ingredient not mentioned is sodium palmate:Β the generic name for the mixture of palm oil with sodium hydroxide (lye).
  • sodium palm kernelate:Β the generic name for the mixture of palm kernel oil with sodium hydroxide (lye).
  • Also soap includes sodium tallowate:Β the generic name for the mixture of beef fat (tallow) with sodium hydroxide (lye).
  • sodium olivate:Β the generic name for the mixture of olive oil with sodium hydroxide (lye).

Is lye in soap bad for you?

No, soap made with lye is completely safe and is not harsh when made properly, using every precaution.

But many people say that lye is dangerous. Let’s find out the true about lye in soaps.

  • Lye is toxic and fatal if it is consumed or swallowed.
  • It is so toxic that it will eat through certain substances, causing it to damage many materials.
  • Lye can cause chemical burns if it comes in contact with skin.
  • It cause blindness if it comes in contact with your eyes.
  • Lye is exothermic when it is dissolved in water, which means it will create a large amount of heat that can be flammable or burn objects in its area.  If large amounts of lye are dissolved, it could boil and splatter, which is dangerous for what it touches.
  • This component is explosive it is combined with: aluminum, magnesium, zinc, tin, brass, and other metals.
  • If lye is combined with sugar, it will produce carbon monoxid
Washed soft hands with homemade soap bar

When using lye in soap making. Protective glasses should be worn, arms and legs should be kept covered, and gloves should be worn.

But it is still safe for you to use soaps containing lye, because if it’s properly prepared and cured for several weeks, no lye remains in the final product.

Some people say that lye in soaps makes their skin irritated and dry.

The dryness and itch could be from either the soap being a bit lye heavy or you could be reacting to one of the ingredients you are using.

How to make bar soap from scratch

Basic supplies and tools:

  • slow cooker
  • plastic, glass, or stainless steel container
  • glass, or stainless steel container
  • digital kitchen scale
  • silicone spatulas
  • immersion blender 
  • candy thermometer

Soapmaker safety equipment:

  • safety goggles
  • rubber gloves
  • oven mitten
  • long-sleeved shirt
  • apron
  • well-ventilated work area

How do you calculate soaps ingredients?

To make bar soap from scratch you need to measure your ingredients and put it on your safety gear.

Using weight measurement is very important when it comes to soap making.

One cup of coconut oil is the same size as one cup of sweet almond oil but it is not the same weight.

And this is why it is so important to use weight measurements.

The amount of lye you need in your recipe is calculated on the weight of the oil and not the fluid ounces so it is quite possible that your soap could be lye heavy.

Especially since you are making very small batches of soap. The smaller the batch of soap you make, the more accurate your measuring needs to be.

There are two methods on how make bar soap from scratch:

  • Hot process. In hot process soapmaking, external heat accelerates saponification. Most soaps can be used the next day, though it’s ideal to wait 1 week if you want a harder bar.
  • Cold process. Cold process uses the internal heat that’s naturally produced during saponification. The bars will completely harden in 4 to 6 weeks.
Homemade or handmade soap bar


  1. Set the slow cooker to low. Add the oil( that you have chosen.
  2. As the oil melts, prepare the lye solution. Slowly add the lye to the water. (Do not add water to lye β€” this is very unsafe.)
  3. With a spatula, carefully stir the solution as you add the lye. It’ll become hot and release fumes, which is normal.
  4. Set aside the lye solution, and let cool for 15 to 20 minutes.
  5. If the oil has completely melted, add another oil that you have chosen. Stir well.
  6. Once the oils have reached 120 to 130Β°F (49 to 54Β°C), place the immersion blender on the side of the slow cooker. Gently pour the lye to avoid splashing. Stir slowly.
  7. Set the blender to low. Stir the mixture, moving in circles. Keep the blender immersed to avoid air bubbles.
  8. Continue blending and stirring for 10 to 15 minutes, or until the soap has reached trace. This is when the oils and lye solution have emulsified and look like pudding.
  9. Cover the slow cooker, and cook on low for 50 minutes. If the mixture bubbles, stir it gently.
  10. Turn off the slow cooker. Let cool until the mixture drops below 180Β°F (82Β°C). Add essential oils and colorants, if using. Mix well.
  11. Pour the mixture into the soap mold. Smooth the top with a spatula. Tap the mold onto your work surface to eliminate air bubbles.
  12. After pouring the soap into the mold, let it sit for 24 hours.
  13. Once cool, carefully remove the soap from the mold.
  14. Cut into bars with a soap cutter or knife. If you used single soap molds, simply pop them out.
  15. While the soap can be used at this point, it’s best to let it dry for another week. This will improve its hardness and quality.

Hot process soap has a rustic look, giving it a homemade appearance. But if you prefer more refined bars, consider trying the cold process method.

Follow me on Facebook

Be the first to comment

Leave a Reply

Your email address will not be published.