Homemade Bar Dish Soap

A simple recipe for cold process bar dish soap that gets your dishes sparkling clean. Add lemon fragrance for a fresh scent.

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Benefits of bar soap

Whether you are trying to live sustainably or live frugally, this bar dish soap will help you get there. Store bought dish soap is shockingly expensive and always comes in big plastic containers. But bar dish soap takes up hardly any room, is packaging free, and works just as well.

This recipe is almost all coconut oil, which is very cleansing but drying. I added a small amount of castor oil for extra lather, because everyone likes bubbles while washing the dishes. (For an even stronger soap, for use on laundry stains, you can try my homemade cleaning soap.)

If you want to add fragrance, you definitely can! Just keep in mind that this will be touching plates, where you eat your food. Because of that, I chose to use orange oil instead of a synthetic fragrance oil. If you want to use an essential oil, make sure you look for one that won’t fade as a the soap cures. (10x orange is a good one.)

It is calculated to a 1% superfat. This just means that there is very little extra moisture left over from the oils. They are almost all saponified, or turned into soap.

Because of the low superfat and high amount of coconut oil, this soap is not suitable for skin. But it leaves dishes sparkling clean! (Here is my best shower soap recipe.)

Basic Soapmaking Tips

• Soapmaking can be dangerous and the ingredients deserve respect. Make sure you are wearing gloves, eye protection, and long sleeves. Any splashes can burn your skin or damage your eyesight. The fumes are also dangerous, so work in a well-ventilated area.
• Don’t make soap when you are rushed or stressed. Just don’t do it. You’ll make mistakes, and they are hard to undo.
• Keep all soap making ingredients away from children or pets. Anything with lye in it is dangerous until it has cured into a finished bar.

Ingredients and supplies you will need:

• 5.41 ounces of lye
• 29 ounces coconut oil
• 1 ounce castor oil
• Fragrance or essential oil, optional (I used 10x orange.)
• Individual bar soap mold that will hold a total of 45 ounces (I used two of these bar soap molds.)
• Stick blender
• Digital scale (I use this one with a percentage function.)
• Spare cups and a spare pot
• Safety goggles and gloves

Making Bar Dish Soap, Step by Step

Begin by measuring out the lye and water separately, using a digital scale. Combine them by adding the lye to the water (“snow floats on the lake”). Stir until the lye fully dissolves, and set aside in a safe place.

While the lye water is cooling, measure out the coconut oil and castor oil on the scale. They should technically be measured separately, but I just add them right to the pot I am melting them in.

Set the oils on the stove to melt on low, until they are fully melted and 140 degrees.

Now you need to wait for everything to cool down. This will take two to three hours. Both components should be about 100-110 degrees before you blend them together. Ideally, they will be close in temperature, less than ten degrees apart.

To blend, pour the lye water into the pot with the melted oils. Blend with your stick blender until a light trace is formed. That means that the blender leaves a trail (or “trace”) when it is dragged through the batter. You shouldn’t see any visible droplets of oil. It usually takes about 5 minutes of blending.

It will look like this

If you are adding fragrance, go ahead and do now and stir it in by hand.

Immediately pour into your soap molds and allow to harden for 24 hours before removing from the mold.

Let it cure for two weeks before using, otherwise it will dissolve too quickly.

Storage and use tips:

• Bar soap always lasts longer if it can dry in between uses. I use these soap savers to help air circulation.
• Don’t store your extra bars under sink. Put them in a dry closet or somewhere similar.
• To help clean your dishes, this works well with either a wooden scrub brush or a dish cloth.
• Again, don’t use as a hand soap, it’s too drying. But using it on your dishes won’t dry out your skin any more than a store-bought dishwashing liquid.

Print out the recipe here:

If you have any soapmaking questions, just ask!