I don’t know why I was so daunted by the idea of making soap – it’s not as difficult as I’d expected. Yes, it involves more effort than my usual recipes, but this basic soap recipe just requires more time, and a lot of common sense. So if you’ve got time and common sense, you’ve got this (of course you’ll need the ingredients too)! After a bit of practice, I’m sure you will also be whipping up soap in less than half an hour. Here, I share how to make a basic fragrance free soap. You can use this as a base to add your own fragrance and colour as you please. I’ve even included step-by-step photos that’ll guide you to your bubbly bliss.
Before we lather up, let me deal with a few FAQs…
Why can’t I just buy natural soap?
Well, of course you can. The only reason to make your own soap is to save cost and customize, especially if you want organic soap (just make sure you use organic oils and additives). Just be cautious and always read the ingredients when you buy, as many retail soaps include unwanted and unnatural additives. This soap recipe only uses what is absolutely required to make soap, nothing added. All the rest is up to you.
Is lye or caustic soda toxic & dangerous? Why is it in natural soap?
Yes, caustic soda / lye is dangerous. By itself, it should never come into contact with skin, eyes or your lungs…nothing besides your kitchen and bathroom drains! This is why you need to be extra careful when working with it in the soap making process. Unfortunately, it is absolutely necessary to make soap. The reaction between lye and oil is what causes saponification (i.e. soap). Most importantly:
Once lye reacts with oil it results in glycerine and soap, which is natural and completely safe.
So the reaction looks something like this:
Oil + Base (lye solution) —–> Glycerol + Salt (soap).
For those of you that don’t know, “lye” is the term referred to when caustic soda is mixed with water (it is a solution).
Safety tips – where you’ll need common sense:
- Wear long sleeves to prevent any chemical burns if the mixture splashes.
- Do not inhale or let the lye fumes get into your eyes.
- If your skin comes into contact with the lye or soap mixture, immediately wash the area thoroughly with cold water and then wipe the area with white vinegar to neutralize the lye.
- Have white vinegar around at all times. It will neutralize the lye. Wipe counter tops or whatever the mixture touches with vinegar.
- Before washing your utensils with dish washing soap, first rinse them with water and then wipe with a cloth that is soaked in white vinegar, or rinse in a vinegar solution (just fill the sink with water and add about a cup of vinegar – rinse in there). Then wash with dish washing liquid as usual.
SOAP RECIPE: STEP-BY-STEP
This makes about one litre of soap, which is roughly 10 bars. That’s enough to last you six months or more!
145g Caustic Soda (you can find this at most hardwares)
1000g Oils (I chose to use 40% coconut oil and 60% olive oil combination for a perfectly cleansing and conditioning soap. But I suggest using cheaper oils if this is your first time, as it can be an expensive mistake!).
A cloth soaked in white vinegar for cleaning.
Tools: A glass bowl for the water, large stainless steel pot for oils & water, electric mixer, stainless steel spoon and knife, soap moulds (ice-cream/ margarine containers work really well too) and white vinegar for cleaning any spills.
- Measure out your quantities exactly with a scale: This recipe is like chemistry. Unfortunately, there’s no compromise and you have to use a scale, and follow all instructions to a tee. You can use this helpful online calculator to work out the exact quantities of oil, water and caustic soda if you’d like to use different quantities than this recipe, or if you’d like to experiment. This tool also allows you to see what quality of soap you’ll be making based on the oil combinations you choose. You can see the hardness, soapiness and cleaning factor of the soap before you even begin making anything.I like to use a 1.2:1 water:lye ratio, and a 6% super fat. You need at least a 1:1 ratio, but I like to have a little more water to make sure there is enough for all the caustic soda to dissolve.
- Make lye solution: Add caustic soda to water in a glass mixing bowl (NOT the other way around). Do this in a well-ventilated area. Outdoors away from any pets is best . Do not inhale any of the fumes from the reaction. The solution will be murky and it will become hot, this is normal. This solution is known as lye.
- Start heating your oil: in a genuine stainless steel pot. Do not let it get to boiling point, this is way too hot. Do this while the lye solution is cooling down and the lye should start looking more clear (less murky) with time. Make sure that all the caustic soda crystals are dissolved by stirring with a stainless steel spoon.
- Combine oil and lye: Once both the oil and lye solution are roughly the same temperature, combine them slowly and start mixing with an electric mixer. Mixing by hand can take hours! Make sure the stove is turned off at this point. You can check the temperature with a cooking thermometer, or you can do what I do and use your sense of touch. I determine this by seeing when both containers are warm to the touch (i.e. not so hot that I have to move my hand away immediately, but warm enough that I can touch the pot for a few seconds).
- Mix until you reach “trace”: Trace is basically the state when the soap mixture is ready to be transferred into your moulds. You know you’ve reached trace once the mixture has the texture of instant pudding. When drops of the mixture fall back into the pot and show a visible trace of themselves on the surface, this is trace. The droplets shouldn’t sink back in quickly/ disappear immediately. The time it takes to reach trace depends on your oil and the speed of your electric beater. It normally takes me about 15-20 minutes to reach trace with olive/ coconut oil. If my description has just confused you more, I do hope the picture helps!
- Add your extras (optional): If you’d like to add scent, herbs or a few drops of food colouring – Now is the time.
- Transfer mixture into your mould: I like to use empty ice-cream and margarine containers, because the plastic is thick enough not to melt, yet flexible enough to get the soap out easily once it hardens. Some people use proper wooden soap moulds lined with wax paper, or even silicone baking moulds. Do not use tin foil to line your moulds, and do not use your metal baking tins as moulds – you will destroy both the soap and the tins.
- Insulate your mould and store in a warm and dark place overnight: I put the lids on my ice-cream/ margarine tubs, wrap the containers in towels for insulation and store in a cupboard overnight.
- Cut soap into bars: Remove from mould and cut soap into bars: Do this after 24-48 hours. Cut your soap with a stainless steel knife. Do not use your soap at this point, it still needs to cure. If you use it, your skin might suffer from a chemical burn. The lye is still reacting with the oil, only once this process is complete (curing), then you can use your soap.
- Let your soap cure: Like good wine, good soap needs a long time to cure. The saponification process is still taking place, and your soap is still not safe to use. Place your bars in a well-ventilated place, away from direct sunlight and allow them to cure for 3-6 months for best results, but a minimum of 1 month until it is safe to use. The longer the cure, the better (but not more than 10 months). Remember to turn them occasionally (every week is good), so that each side gets exposure to the air.
- Lather up! You can use this soap as a body wash, shampoo bar or to wash the dishes. You can even grate it up and put about half a cup in the washing machine for laundry. It’s that versatile!
- The time that soap takes to cure. This recipe uses the room temperature/ cold process method, but if you’d like to cut the curing time substantially, then you may want to consider the hot process method. This method requires you to be much more precise with temperatures, you need a crock pot/ slow cooker and the method is much longer (2 hours to the mould step), but the curing stage is much shorter (2 weeks). Whereas, the cold process method is quick (30 minutes to the mould step), but the curing stage is much longer.
CHERRY ON TOP
- You can completely customize this soap recipe. You can use any oil, and also add essential oils/ scents, colouring and textures according to your preferences.
- You can make organic soap in bulk, and save the cost of purchasing it all the time.
- It has many uses. This castile soap bar can be used as a body wash, shampoo, dish washing soap and laundry soap (just grate it and put half a cup in the washing machine). Read my post on how to make liquid soap from a hard bar of soap.
- Eco-friendly and only contains what you need – there are no unpronounceable chemical additives.
Let me know how your soap making journey goes in the comments below. I’d also love to know what additives or oils you’ve chosen to use, so please share.