3 Ways to Help Your Soap Harden in the Mold

When we make recipes with a high content of soft oils we’ll find it can be really hard to remove the soap from the mold.  I’ve experienced this multiple of times. I’ll usually get impatient and try to peal the edges of my silicon mold away ‘to check’ if the soap is ready.  Which will ultimately destroy to the look of my soap, or I’ll end up trying to make room in my freezer to pop my mold in for a few hours. This problem is common especially when you’re using a silicon mold.

Fortunately there are a few tricks that can help speed up the process of removing the soap from the mold, with out ruining the sides and destroying its shape.

1. Putting your Soap Through a Longer Gel Phase

Gel Phase or Gelling is a natural part of the soap making process.  When we’re making cold process soap, after we pour the soap into the mold the temperature of the soap slowly rises and reach up to 180 degrees.  You can touch the side of your mold and feel this especially with a silicon mold. (Sometimes if the soap gets too hot it can volcano out of the mold which we don’t want to happen. Check out this article I wrote on the first time I experienced a soap volcano.)

Side note: If you’ve ever cut your soap and saw a dark circle in the middle, that means your soap went through partial gel phase. It’s not a problem at all, and it’s just an aesthetic issue.  Your soap is perfectly fine for use.

Some soap makers like to make sure their soap stays warmer for a longer time which can prolong the gel phase.  You can achieve this in several ways


  1. You can insulate your mold. Cover it with a piece of cardboard and wrap it up in a towel. This help keep the heat it.
  2. Warm up your oven to 170 degrees while you’re making your soap. After you pour the soap in the mold. Turn your oven off. Put your mold on a tray, insulate it, and put in the oven. Leave it over night. Some soap makers like to leave the oven light on for extra warmth.
  3. Use a heating pad. This is just a pad that you can place your soap mold on that insures your soap will stay warm.


2. Using Sodium Lactate

Sodium lactate is a salt of lactic acid and it is commonly used as a food preservative. Adding it to your soap is completely optional but it is very beneficial when making soap with a high content of soft oils because it helps harden the soap.  I like to add 1 tsp for every 454 grams of oil. I add the sodium lactate to my lye solution and mix it in just before I add my lye solution to my oils.


So if your recipe has 1247 gm of oil you should add 2.7 tsp of Sodium lactate, but you can round this up to 3 tsp.

(1247 divided by 454 = 2.7)


3. Opting for a Water Discount

A water discount means we’ll deliberately reduce the amount of water we’re using in our recipe. With less water in the recipe, the soap will harden faster and make it easier to remove from the mold.

There are 2 other benefits to water discounting. Your soap will need less time to be ready for use (less curing time), and you’ll have less chances of soda ash.

You can try a water discount of %10- %28

But you should know that going for water discount will make your lye water more dangerous if it comes in contact with your skin because it’s more concentrated. It won’t make your soap dangerous because we’re still using the right amount of lye to saponify the oils.

To calculate the water discount just multiply the amount of water in your recipe by the percentage you actually need.


Let’s say our recipe calls for 474 gm of water, and we would like to do a water discount of %20.

To calculate the new amount of water = 474 x 0.8 = 379.2 gm

(We multiplied by 0.8 because

%100-%20 = %80

Or in other words

1 - 0.2 = 0.8

We want to discount %20 of our water, so we actually only want %80 of our water


So if you try 1 or all 3 of these methods with a soap recipe that has a high content of soft oils, I guarantee you’ll have an easier time removing the soap from the mold within 1-2 days. Let me know if you try this by tagging @figarabia in your posts. I can’t wait to see what you make :)

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