Ready to learn how to make your own soap from scratch? Cold process soap making is one of the most natural ways to make soap.
You can also customise your oils, butters, fragrances, colours and decoration! It is by far, the most versatile soap!
Whether you have sensitive skin, dry skin, mature skin or acne prone skin, there is a cold process soap recipe for you.
So let’s learn the basics, and help you become a pro soap maker!
Contents
- What is Cold Process Soap?
- Why Make Your Own Cold Process Soap?
- What Drawbacks Are There?
- Soap Making Safety
- Cold Process Soap Making Tips
- Easy Cold Process Soap Recipe
- Final Thoughts
What is Cold Process Soap?
Cold process soap making is the process of combining oil, water and sodium hydroxide to make a solid soap.
The cold process method is the most popular soap making method due to its versatility. You can customise the oils, colours and fragrance in many different ways.
It is a more natural way to make soap compared to melt and pour soap and you can get more creative with the design!
Why Make Your Own Cold Process Soap?
This is one of the most natural forms of soap making!
Cold process soap can contain as little as 3 ingredients. It is the perfect choice if you are looking for a gentle soap for sensitive skin!
One of our favourite things about cold process soap making is how versatile it can be. You can choose which oils and butters to use based on your skin's needs. Cold process soap also allows you to combine colours, swirl patterns and add decorations. While you're still a beginner, it may be best to try lots of different recipes before trying to customise the soap!
What Drawbacks Are There?
The biggest drawback is that you have to handle sodium hydroxide directly. However, if you are careful and stick to the recommended safety precautions, you will be fine!
This soap method is more difficult to master compared to other methods like melt and pour soaps, so it may take a few tries to get the hang of it.
Cold process soap also cannot be used until the soap has fully cured. Which means you can’t use the soap bars up to 6 weeks after you have made it.
Soap Making Safety
This type of soap making does involve handling dangerous substances like sodium hydroxide and pure essential oils. These products are safe to use if you follow the necessary safety precautions.
Sodium Hydroxide
Pure sodium hydroxide is a highly caustic substance that must be handled carefully. Contact with the skin will cause severe skin burns, and the inhalation of vapours can cause irritation. Keep out of reach of children and pets.
When handling caustic soda, make sure to follow the appropriate safety precautions. You must wear gloves, a mask, safety goggles and long-sleeves. Also ensure you are working in a well-ventilated room (so open a window), otherwise you may need a respiratory mask.
When adding caustic soda to water it can become quite hot and the fumes can be quite unpleasant, so ensure the room is well ventilated and do not directly breath in the fumes.
Never add water to sodium hydroxide, always add sodium hydroxide to water. This helps prevent overheating and splashing of highly concentrated sodium hydroxide.
Make sure you don't mix your soap making tools with food preparation tools. Your soap making tools will have caustic soda residue on them and need to be washed thoroughly before they are safe to handle. But you won't want to cook with them!
Essential Oils
Essential oils are also hazardous and should not be ingested or used directly on the skin. When handling essential oils, we recommend wearing gloves. If an essential oil makes contact with your skin, wash it off with soap immediately. For more information on essential oils for soap making, click here.
Can You Make Soap Without Sodium Hydroxide?
It is not possible to make cold process soap without sodium hydroxide. The key ingredients in cold process soap making are oil, water and sodium hydroxide.
When sodium hydroxide and water are mixed with oil, it goes through a saponification process which is a chemical reaction that turns these three ingredients into soap!
If you are put off by handling sodium hydroxide, melt and pour soap might be better for you!
Cold Process Soap Making Tips
It is easy to make mistakes with cold process soap, which is why we created a troubleshooting blog that covers the most common problems with cold process soap!
But here are some key things you need to know before you try our recipe…
Equipment
Before making your soap, it is important to buy separate equipment for soap making that is not used for food!
When making cold process soap, you will need a little bit more equipment than melt and pour soap making. As well as the basic equipment, you will need safety equipment to handle sodium hydroxide, an immersion blender and thermometer. Here’s a list of everything you may need:
- Gloves
- Goggles
- Digital scales
- Digital thermometer
- Immersion blender
- Soap mould or DIY alternative
- Silicone spatula
- Microwave safe bowl
- Plastic measuring cup
It is crucial to measure all of the ingredients perfectly when making soap, as too much of one thing can throw off the whole soap. Because of this, we recommend getting a high quality weighing scale for accurate measurements.
Trace
One of the common mistakes when mixing soap for the first time, is not knowing when your soap has reached trace. When blending the oil and sodium hydroxide solution together, they will start to thicken (this is trace).
It is the point where the oil and sodium hydroxide solution are no longer at risk of separation. You want to blend the ingredients together until it reaches a certain thickness.
To test if the soap has reached trace, you can drip a bit of the mixture onto the mixture's surface. If it sits on the surface before sinking back in, it has reached trace.
If you don't blend the soap enough, the mixture will be too thin. However, if you blend it too much, the soap will seize and become impossible to pour into your mould! It is important to note that essential oils can speed up the trace. So after adding your essential oils make sure they are fully mixed in, but be careful of the trace.
It may not be easy to get the hang of at first, but after you have made a few soaps you’ll know what you're looking for.
Gel Phase
After you have poured the soap into its mould, it is important to wrap the soap in towels or blankets to keep it warm.
This may seem unnecessary, but if the soap is not insulated properly while setting, it can create a discoloured ring inside the soap. It doesn’t affect the quality of the soap, but it doesn’t look very nice!
We want the soap to go through the gel phase as this makes the colour brighter and the soap easier to handle.
You can find more information about gel phase here
Temperature
The temperature of the oils and sodium hydroxide solution is very important. Do not skip this step!
The melted oils mixture should be between 35°C and 40°C. The sodium hydroxide water should be between 25°C and 40°C. You must make sure the mixtures are within these ranges, not above or below.
It is important to remember that you cannot reheat the sodium hydroxide solution but you can reheat the oils.
If your oil solution is cooling faster, you can always warm the oils slightly to match the temperature of the sodium hydroxide solution. However, if your sodium hydroxide solution is cooling faster than the oils, you can try cooling the oils faster in the fridge.
When making soap, I try to melt the oils and create the sodium hydroxide solution at the same time. That way, the mixtures can cool at a similar rate. If you are unsure, it is best to heat the oils first, then create the sodium hydroxide solution as it is easier to reheat the oils if they cool down too much.
Organisation
Like melt and pour soap making, you must get all of your ingredients weighed out and ready to go. Make sure all of your equipment is nearby, as you don’t want to slow down the soap making process looking for your blender or soap mould!
Easy Cold Process Soap Recipe
Makes 9-10 bars of soap
Takes 1 hour making time and 4-6 weeks curing time
This recipe contains 5% superfat. Find out more about superfat in soap here
Ingredients:
- Olive oil 450g | 490ml
- Cocoa butter 135g
- Coconut oil 315g
- Water 250g | 250ml
- Sodium hydroxide 130g
- Orange essential oil 27g | 30ml
- Orange burst mica powder 20g
Method:
1. Make the sodium hydroxide solution
- Put your gloves and safety glasses on
- Open the window, the fumes will be unpleasant
- To make the sodium hydroxide solution weigh the sodium hydroxide in a bowl and the water in a separate bowl (ensure you follow the safety requirements first)
- Pour the sodium hydroxide into the water, not the other way around! Mix well until the sodium hydroxide has fully dissolved
- Leave to cool down, it will be hot
2. Weigh out the oils
- Weigh the olive oil, cocoa butter and coconut oil in a separate bowl
- Melt the ingredients in a bowl over boiling water, microwave or double boiler
- Once the oils have fully melted, leave to cool
3. Check the temperatures
- Test the temperature of the melted oils mixture, they should be between 35°C and 40°C. Reheat them or leave them to cool more if necessary
- Test the temperature of the sodium hydroxide water, it should be between 25°C and 40°C. Leave to cool if necessary, but don't reheat the sodium hydroxide solution if it's too cool. Just heat the oils a little more to compensate
- Once the temperatures are right, add the sodium hydroxide mixture to the melted oils
4. Blend until trace
- With a stick blender, mix the soap mixture to combine the oils and lye solution
- Watch for the soap mixture starting to thicken
- Test for a light trace by dripping soap batter on the surface of the soap mixture. If the drips sit on the surface then your mixture has reached trace
5. Weigh the essential oils and mica powder
- In a separate bowl, mix the essential oils and mica powder together
- Add the essential oils mixture to the soap and gently mix until fully combined
6. Pour into moulds
- Pour the soap mixture into your soap mould
- Tap the soap mold to get rid of air bubbles.
- Decorate the top with a spatula or spoon.
- Leave on a flat surface and cover the soap with something warm to insulate it.
- Leave to set for 48 hours before unmoulding.
7. Unmould and cure
- Once the soap has set, unmould it and cut it into equal sizes.
- Put the solid soap bars with gaps in between them, and let the cold process soap cure for 4-6 weeks.
Final Thoughts
Cold process soap making might seem overwhelming, but it is so rewarding!
Don’t worry if it goes wrong the first time, or second time or more! The truth is, the more you go wrong, the better you will get!
Now you know how to make a simple cold process soap, along with all our tips and tricks, you can explore our huge range of recipes!
Want to try melt and pour soaps? Check our our complete beginner guides:
Continue Reading
Now you know how to make cold process soap, why not try more recipes?
- Want to try more cold process soapmaking? Try our simple rose soap recipe!
- Interested in making goats milk soap at home? Take a look out our cold process soap recipe!
- Learn how to make hot process soap with our oatmeal soap recipe!
How did your handmade soap turn out? Comment below and let us know!
