Want to begin making natural soap at home? Here, I will walk you through everything you need to know to start making your own cold-process soap at home. These same instructions will be applied to all of my cold-process soap recipes with adjustments along the way dependent upon the ingredients used in each recipe.
As a self-taught soap maker, I did a lot of research before diving into making my first batch of soap. The time spent studying soap-making methods and ingredients was well worth it as the results were exactly what I hoped for and I immediately fell in love with the process. Now, after making hundreds of batches of soap, selling my handmade soap, and using it in my own household, I love being able to share with others how they too can make lovely, handcrafted, natural soap at home!
Some of the most important factors of soap-making are selecting the right ingredients and equipment, as well as practicing safety along the way.
NATURAL SOAPMAKING INGREDIENTS
When selecting ingredients, I want them to be natural, beneficial and free from unnecessary toxins, which is why I choose essential oils for fragrance, natural oils and fats, and natural clays for colorants.
Cold-process soap-making means working with Lye (Sodium Hydroxide). This is different from making "Melt and Pour Soap" as with a "Melt and Pour Soap" the chemical process is already done for you. With cold-process soap-making, you are starting completely from scratch. Saponification is the natural chemical process taking place when fats and oils react with lye creating a whole new compound which we know as soap. After this process occurs, there is no lye left in your soap bars.
Distilled water is used in soap making to activate the lye and to disperse it throughout the oils. Most of the water evaporates out of the bars during the soap's curing process. Once fully cured, your bars will appear smaller than when you first removed them from their molds. Avoid using tap water or spring water as they can contain impurities and minerals that may affect the quality of your soap.
Let's go over some of the most common, base oils I have come to love in making natural, skin-nourishing soap bars.
Olive oil is used in nearly every one of my soap recipes. It creates conditioning bars that are excellent for all skin types, including those with sensitive skin. Pomace olive oil is lighter in color and doesn't interfere with the soap's color as much as Extra Virgin olive oil (EVOO). Pomace olive oil is considered second-grade when compared to EVOO as it's extraction method is not considered as pure as EVOO's, however it is preferred by many soap makers. EVOO takes longer to come to trace and can give a yellow-greenish tint to soap. I have used both and do prefer the result of Pomace olive oil. Olive oil can be used at up 100% in soap recipes.
Sunflower oil also leaves a soft conditioning lather to soap. Using too much can cause soap bars to become too soft and leave them with a shorter shelf life. It is best used at low percentages up to 15% superfat.
(Superfats are oils that remain in the bars after saponification for added moisture.)
Shea butter is one of my favorite ingredients. It saponifies slower than other oils and makes for a harder, more hydrating soap bar. It has commonly been used only as a superfat due to the way it moisturizes skin, being melted and added at trace, but I use it as a base oil instead.
Coconut oil makes for a hard bar of soap with a silky, fluffy lather. It is most common to use solid, refined coconut oil as fractionated coconut oil has different properties and the coconut scent in unrefined coconut oil does not carry through in soap bars.
Castor oil is used in small amounts and creates a beautiful lather in soap.
The most common way soap makers scent soap is with cosmetic grade fragrance oil. For soap makers who desire a completely natural soap, but still want a scent, essential oils are the way to go. Essential oils are plant and flower extracts that have beneficial therapeutic properties and also produce a scent. Lavender, Peppermint, Rosemary, Orange, Geranium, Patchouli, Eucalyptus, Tea Tree, Lemon and Lemongrass are a few of my favorite essential oils for soapmaking. The only downside to using essential oils is that they tend to be more costly and the scent does fade with time when used in soapmaking, especially citrus oils like lemon, orange, lime and grapefruit. If you are used to and desiring a stronger scent, you may prefer using fragrance oils in your soap. Keep in mind that fragrance oils are not only synthetic, but they are also patent-protected meaning we'll never truly know what's in them. Many contain allergens and even known carcinogens. I strictly use essential oils.
There are ingredients you can add to your soap that help hold onto the scent from the essential oils, such as finely ground oatmeal (colloidal oatmeal), arrowroot powder, or kaolin clay. You can add the essential oils to these dry ingredients or just add them directly to your soap at trace when you add your essential oils. I'll dive into this more during the soapmaking process. Heavier base note essential oils like cedarwood and patchouli will also help hold onto scents from citrus essential oils.
When it comes to coloring soap, I also stick to natural ingredients like mineral clays such as kaolin clay, french green clay, cambrian blue clay, coffee grounds, charcoal powder, rose clay, dried herbs and botanicals.
I also love adding natural elements as soap decorations such as dried calendula petals, chamomile flowers, dried rose buds and lavender buds, whole oats, herbs and some spices. Many of these same elements from the earth can be finely ground and added into the soap as exfoliants as well.
EQUIPMENT AND SAFETY
Let's talk equipment! Much of what you will use for soap-making, you probably already have in your kitchen. Maybe there are pots/pans, containers, spatulas or whisks that aren't getting much use. If you don't have an item you need, shop your local thrift stores or even garage sales to collect them before investing in new items. It shouldn't cost you much to get started with soap-making, however it is important to have the essentials for yielding good results and keeping yourself and your family safe.
No matter how natural soap-making is, there is a chemical process occurring with lye involved and it is important to be taken seriously. While handling lye during soapmaking, it's important to wear protective eyewear, long rubber or latex gloves, and an apron. Pants, long sleeves, and close-toed shoes are also recommended leaving less possibility of skin being exposed to lye.
The goggles that I wear are a pair of hardware goggles my husband already had in our garage. If you have to purchase some, this pair of culinary "onion goggles" are a great option. If you already wear eyeglasses, it is still a good idea to put protective eyewear over the top of them.
You may consider wearing a face mask. Lye water puts off potent fumes that you don't want to be breathing in. I have worn one from time to time, but as long as I mix the lye-water in a well ventilated area, I don't feel the need to always cover my face. I like to open my kitchen window and mix lye right next to it so the vapors find their way out the window. Another note to keep in mind: If lye water happens to splash onto the skin, rinse it thoroughly. Just the tiniest drop can cause irritation.
Soap molds are very helpful and recommended, however, if you're not ready to invest in them just yet it is still possible to make soap using common household items instead. A traditional "soap mold" is a wooden box lined with parchment paper. If you want to get started without a mold, you can cut cardboard milk cartons or cereal boxes, really any box should do. Just be sure to line your box with parchment paper.
When you are ready to purchase a soap mold, I recommend a silicone mold such as this one or a silicone box style mold like this one. Silicone molds are easy to clean and removing the bars is effortless. The box style mold will require you to cut the bars by hand as opposed to the first option where the soap comes out in single bars. The benefit of using a box style mold is that the wood helps to insulate the soap. When soap cools too quickly on the outside while staying warm on the inside, this can create bars with a dark center and a lighter edge. This does not effect the final product of the soap beyond its appearance, but if this happens, it's merely due to poor insulation.
You can also purchase silicone molds in different shapes which can make gifting handmade soap bars extra special for different occasions.
Two absolutely essential pieces of equipment for cold-process soapmaking are a digital kitchen scale and a thermometer.
Precise measuring is very important when soapmaking and must be done by weight, not by volume. Your scale's accuracy makes all the difference for producing consistent results and especially comes in to play when weighing powdered ingredients such as mineral clays or essential oils. This is the digital kitchen scale that I use and have success with.
Taking an accurate temperature is equally important as proper measuring when it comes to cold-process soapmaking. Part of the process requires the melting of oils and butters together then combining them with a lye solution. The lye mixture and the melted butters and oils need to be close to the same temperature when they are combined so using a thermometer throughout the process is vital. I have used a standard glass thermometer in the past, but I much prefer the ease of my infrared temperature gun and have found it to be a worthwhile investment.
An immersion or stick blender is also necessary for cold-process soapmaking. It is used to bring the lye solution together with the oils and fats/butter. The old-fashioned way of making natural soap required stirring for long periods of time. The immersion blender allows the oil and lye water to come together in just a few minutes. Any stick blender will do, but I recommend one that has slits or holes in the design to eliminate the amount of air making it's way into the soap creating air bubbles, which you do not want in your soap. This immersion blender is similar to the one I have.
A few utensils you'll want to have on hand:
Stainless steel spoons; one for stirring oils, another longer one for stirring lye water. Stainless steel whisk for mixing in clays, herbs, botanicals, essential oils, and minerals. Stainless Steel Strainer or Sieve for pouring your lye solution through into your oils. You don't want undissolved clumps of lye to make their way into your soap.
Silicone Spatula to get as much of the soap out of the pan and into your molds as possible.
When it comes to containers, ensure that they are heat-proof and that any metal pans or bowls are stainless steel. Other metals will react with the lye and uncured soap. Containers that come into contact with the Lye/Sodium Hydroxide should be kept for soapmaking only.
Containers you will need:
A deep stainless steel pan for heating oils.
Container for measuring lye/sodium hydroxide into.
Heat proof container for measuring water into that you will then mix the sodium hydroxide into, which should be heat and lye resistant. Glass is best.
Small glass containers for measuring additional ingredients like essential oils, botanicals, and powdered ingredients like clay and minerals.
How to Make Cold-Process Soap: Step by Step Guide for Beginners Part 2
THE SOAPMAKING PROCESS
There are many different methods of soapmaking out there, but I'm going to share with you the cold-process soapmaking method that I use when soapmaking. It's not actually "cold" processing, but it is called so as opposed to hot process which is typically made in a crockpot. Cold-process is usually made at room temperature up to about 120°F, all dependent upon the ingredients and the size of the batch. Once the soap is poured into molds, the soap then sits in the mold to finish up saponification for 24-48 hours. It will then take another four weeks to fully cure and be ready for use.
Preparation
Here are the basic steps you will take to make a batch of cold-process soap:
Measure ingredients.
Mix Lye Solution.
Slowly melt solid oils.
Combine liquid oils with melted solid oils.
Pour lye solution into combined melted oils.
Bring lye solution and oils to trace.
Add additional ingredients like essential oils, colorants/clays, and exfoliants.
Pour soap into molds.
Decorate soap tops (optional).
Cut bars and wait for soap to cure.
Before I jump into making soap, I like to prepare in advance by setting aside time that allows for no disruptions in the kitchen. If you have a busy kitchen like mine, it's best to make soap between meal times and at a time when there won't be any activity in the kitchen. There is timing involved and disturbances could cause mistakes. This also ensures less accidents that could cause someone to come into contact with lye.
Cold-process soapmaking is very involved with the use of many ingredients and supplies, instructions and safety precautions that need to be met, so it's important to start off well organized. Set up different stations for where you will measure ingredients, a separate station for mixing the lye solution, where you will melt the solid oils and mix all ingredients together, and another with your molds ready for pouring. This helps the process go more smoothly so that you are not panicking to find something along the way. A quick checklist to help you prepare:
Set up your soapmaking stations with all the equipment, supplies and ingredients you will be using.
Wear clothes that you don't mind getting messy with splatters of oil or uncured soap. Put on an apron, safety goggles and work gloves.
Measure your solid oils into a stainless steel pan near your stove.
Measure liquid oils into a bowl for pouring into melted solid oils.
Measure water for making the lye mixture into a large glass bowl or measuring pitcher.
Measure lye in a separate container that will then be poured into the water.
Weigh/measure additional ingredients that you will add at trace; essential oil, dried herbs, clays, etc.
I plug my stick blender in near my stove with a hot-pad nearby to place the pan of melted oils onto. In this same area, I also like to have my metal sieve ready for when the lye water gets added to the oils, plus additional ingredients that will be added in, along with my stainless steel whisk. This is also where I keep my digital thermometer (infrared temp. gun).
The bowl of water for the lye solution is kept near my sink with the window open. This is where I mix the lye into the water, so I also have a stainless steel spoon handy here for stirring and the bowl of water sits on a hot pad as the lye solution reaches over 200°.
The last area/station has my soap molds on a tray, a silicone spatula, utensils for decorating the soap top, as well as any dried flowers or herbs for sprinkling on top and a few old towels to use for insulation.
Mixing the Lye Solution
Carefully pour lye into the water and begin stirring it immediately so the granules begin to dissolve. You will always pour lye into the water and never water into the lye. The chemical reaction occurring will produce heat and fumes that you will want to be careful not to breathe in. Thoroughly, but gently, mix until all lye granules are dissolved then leave the solution to begin cooling.
Melting Solid Oils
After mixing your lye solution, you will begin melting your solid oils in a pan on your stovetop. Solid oils are oils that are hardened and need to be melted down in order to pour, such as coconut oil or shea butter. Your solid oils should already be measured and in the pan at this point, so you will place the pan on the stove and turn it to the lowest heat possible. Keep a close eye on the oils as they melt, stirring often and breaking up and large pieces to speed up the melting process. Take it off the heat as soon as it is fully melted to avoid heating the oils unnecessarily. You can usually take it off the burner even with small bits that are not fully melted, as they will likely melt with a few extra stirs after removing the pan from the heat.
Mixing Liquid Oils into Melted Solid Oils
Now that your solid oils are melted, you will add your liquid oils to them such as olive oil, sunflower oil, and castor oil. Do not add your essential oils at this time. You will do that after reaching trace which I will explain later. Castor oil is thicker then the other oils, so you will want to give your liquid oils a stir before pouring when using castor oil. This helps to distribute the castor oil into the other oils so there is nothing left behind. Use a spatula to get every last drop of liquid oils into the pan with your solid melted oils. Once the solid oils are melted, pour the liquid oils into the pan too.
If your recipe calls for a colorant, you will add it in at this point. If the colorant is mixed with water or an oil, pour it into your oils through a sieve to catch any clumps that have not been incorporated. Adding colorant at this stage prior to mixing oils with the lye allow for a more evenly distributed color throughout your soap batter.
Cold-Process Soapmaking Temperatures
You want to cool both the oil mixture and the lye solution to around 100°F before combining them. Temperature has everything to do with the appearance and feel of your final soap bar. Staying around this temperature when mixing and pouring will avoid many common soapmaking errors, like cracks, flaking, uneven coloring, etc. You can give or take a little bit here and as you become more experienced, you may try increasing the temperature, but for now 100°F is a good, safe starting point. A general rule of thumb I follow is to keep the lye solution and the oil mixture within 10°F of one another when combining them. So, if my oils are 100° and my lye solution is 110°, I go ahead and combine.
Bringing Soap to Trace
Once both the lye solution and the oils have reached the desired temperature, it's time to pour the lye water into the combined melted oils. Be sure to pour the lye water through a metal sieve to avoid undissolved lye making its way into the soap.
After pouring the lye water into the oils, you will blend them together using the immersion blender. Before turning the blender on, first use it to stir your ingredients together slowly. Next, touch the head of the blender to the bottom of the pan and turn it on with three small, quick pulses. Then you will stir again slowly with the blender turned off. You will repeat this process until the soap begins coming to a trace. For smaller batches, this may take only 2-3 minutes, but can take up to 10 minutes for larger batches.
Trace is the beginning step to saponification. It is the thickening of your soap batter. You know that your soap has come to trace when it has reached a custard-like consistency and leaves a faint impression on the top of the soap batter when the blender is pulled out.
A faint trace is all you need, but if you don't come to a medium trace where the soap batter thickens to a more pudding-like texture, you will want to work more quickly so your soap doesn't begin solidifying while still in the pan.
After reaching trace, whether fine or medium, you will want to move quickly at this point to add in your final ingredients. This is when you will add in essential oils to scent the soap or any additional exfoliants or add ins.
With your final ingredients pre-measured, all you need to do is pour them in and use your stainless steal whisk to stir them for a minute or two.
Hand-pouring Soap into Soap Molds
Now that your final ingredients have been added, you are ready to pour your soap into their molds. You'll want to do this while your soap batter still has a liquid consistency as you will tip the pan and pour the batter directly into the molds. If you find that your soap batter has thickened up too quickly, you can ladle your soap into the molds. Remember to use a silicone spatula to scrape all of the batter into your molds. Once you have gotten all soap into the molds, you will gently tap the sides of the molds to settle any bubbles and even out the tops. If your batter is thick at this point, carefully lift the mold and give it a good, hard tap back onto the counter to settle the bubbles and tops. You can now use a small spoon or spatula to make a design in your soap top and sprinkle on dried flowers or other natural ingredients for decoration.
Insulating Soap in Molds
Keeping soap well insulated allows the temperature to stay consistent in the bars over the 24-48 hours they are setting in their molds giving the soap an even, more vibrant color throughout.
Using molds that are cased in wood, help keep the soap insulated, but you will also want to cover the top of the mold with a piece of cardboard so that you can wrap the top and sides with heavy towels for further insulation.
Removing Soap from Molds and Cutting Soap Bars
After 48 hours, you can remove your soap from their mold. If using silicone molds, the soap should come out of your mold easily by pealing away the edges then pulling the soap out of the mold.
The size you cut your soap bars is a personal preference, but I do recommend measuring so that you get even cuts. For a 10-inch loaf, I typically cut bars that are 1-inch wide giving me 10 bars out of one batch. Early on, I measured out 10-inches on a piece of parchment paper, made 1-inch pencil lines, then I would lay my template atop my soap, score the bars by making a small dent over the top of the parchment, remove the parchment and cut where the score marks were left in my soap. There are lots of creative ways to make your cuts even and there are plenty of soap cutting devices that can help give even cuts. My husband built me a box with slits one inch apart in the sides that my loaf fits right i
into. You can purchase one similar here. I use a simple slicing tool for cutting.
Curing Soap Bars
This is the final stage of soap making and is extremely important that you allow your bars to fully cure before using them. After cutting your bars, they are probably looking pretty and may be smelling pretty too, but make sure you give them adequate time to cure. This ensures you are getting the most out of your bars. They can take four weeks at this point to fully saponify and you do not want to rush this process. This stage allows for the water to evaporate out, the bars to harden so they are long lasting, and is what gives your soap bar a rich lather.
To cure your handcrafted soap bars, set them on a piece of parchment paper where they can stand up out of direct sunlight for four weeks. Be sure to space the bars out enough to allow airflow between the bars. You can rotate the bars from time to time, but this is not necessary. The curing process is worth the wait, trust me!
I have been eager to write and share 'How to Make Cold-Process Soap: Step by Step Guide for Beginners' for quite a long time. I'm hopeful it helps you approach your soapmaking journey with confidence. Happy Soapmaking! The video below will walk you through each step if you are a visual learner.
Jump to Mint, Lavender and Rosemary Cold-Process Soap Recipe or Honey and Oat Natural Soap Recipe for two of our family favorites!
Your soups looks amazing. Thank you for providing step by step Cold Process soap making. Very educational and precise. how dI’d you make the design in the top of your honey and Oat Natural Soap ? I love it