Written by Alison
This is my attempt at making a cold process soap, using Sally in Wales' instructions from the forum, which can be found here.
Sunflower Oil 300g
Olive Oil (cheap pomace grade is fine) 300g
Coconut Oil 200g
Sodium Hydroxide (caustic soda) 112g
Water (bottled or distilled is the most reliable, but I do use tap water as well) 250ml
Stainless steel, glass or sound enamel pan. DO NOT use aluminium
Glass or stainless steel jug or bowl for mixing the lye
Stainless steel spoon, or wooden spoon
Rubber gloves, suitable eye protection and apron
Balloon whisk or stick blender (optional, but it speeds things up)
This recipe is aimed at those who have not made soap before.
Please make sure you fully understand the following points before starting:
1. Lye is in this case caustic soda crystals. It can often be bought from larger chemists where it is sold as a drain cleaner. Never use a ‘brand name’ drain cleaner instead unless you are certain that it only contains caustic soda. Boots often have it in the household cleaners bit.
2. Always add lye crystals to water, Never the other way around (it could spit). Lye and water generate a lot of heat and nasty fumes, best step outside to mix it.
3. Lye in any form is strongly alkali and can burn skin, if you splash it on yourself you will notice itching first. You can neutralise this with vinegar and then wash the area well. (Keep an open bottle of vinegar to hand when soap making as a precaution.) Wear rubber gloves as well and consider eye protection.
4. Lye reacts with some metals, I recommend you stick to glass or stainless steel jugs and bowls when making soap.
5. Raw (freshly made) soap is also too alkaline for use immediately. Give it time to mature and the pH will come down. The traditional way to tell if your soap was mild enough to use was to touch some to the tip of your tongue. If it is still caustic, it will ‘bite’. Use caution if you decide to try this approach and never try it the day you unmould your soap! It will take several weeks for your soap to mature enough to try this with any degree of safety.
Weigh and measure all of your ingredients as precisely as possible.
Wearing suitable protective gear, add the crystals to the water (never the other way around) and stir.
Warm the oils over a low heat (ideally aiming for hand-hot, but don't try sticking your finger into hot fat).
If you have a thermometer, you can check that the oil and lye are at a similar temperature, ideally in the region of 50-60°C/120-140°F, but it's not that critical in my opinion as long as they are broadly similar. Take the oil off the heat.
Pour the lye mixture into the oil after giving it a few moments to cool down and stir with a metal spoon or balloon whisk.
The lye will start to react with the fat to form molecules of soap and glycerine. In practice it will look a little like thin custard. Keep stirring, this stage may take as little as 10 minutes, or as much as an hour. You want to keep mixing the fats and lye together. If you have a stick blender, this will speed up the mixing to about 2 minutes flat, but beware of splashes.
You are looking for the moment at which the mixture leaves a trace; this is simply the point at which you can see the trail left by the motion of the spoon for a few seconds. You don't want it too thick, that custard analogy is a good one, you are aiming for a ‘pouring custard’ consistency.
This is when you add any additional ingredients such as essential oils, oatmeal or herbs. A batch this size will need between 5-10 ml oil. Make sure you know it is suitable for skin use!. I used about 2 tablespoons of ground pumice, some powdered orange colouring and 5 ml orange essential oil.
Alternatively, make plain soap and you can grate it later for mixing with a variety of scents.
At this point pour it carefully into a mould (a small plastic food container works well). Smooth a piece of clingfilm onto the top (optional but it gives a nice finish), then wrap the whole thing in a large towel to help keep the heat of the reaction in, and leave in a warm place to finish reacting and setting. I used rinsed-out, foil-lined packets as moulds as they can be peeled off easily to get the soap out of the mould.
As it reacts the soap will pass through a gel phase, where it generates a lot of heat and turn darkly transparent. It will slowly cool and become opaque after this. Two days later you can unmould the soap and cut it into bars.
It is not ready for use yet! It needs to be aired for a few days then wrapped in greaseproof paper and put safely away (an airing cupboard is ideal) for at least four weeks, during which time the pH will decrease and the soap will become gentler on the skin.
Soap is fairly soft when first cut, but gets much harder with age. The longer the curing, the nicer the soap.
You can use it as laundry soap before it has fully cured; just grate a bit off and use around a tablespoon of grated soap in the machine, with an optional half cup of white vinegar in the rinse aid drawer.
Making it smell nice if you made plain soap!
You could try storing the wrapped bars in a bag of herbs to impart a delicate scent.
Once the soap has cured (wait at least 2 weeks) you can grate it finely, mix in dried herbs or spices, moisten it with boiled water, herb tea or rosewater and squidge it into 'soap playdough'. This can be pressed into moulds or rolled into balls. It is a good way to try several scent variations without having to make lots of batches of soap. These will need to air-dry for a week at least before use. (Soap playdough is very popular with young kids who want to make presents for granny/aunty/teacher - just make sure the soap is not still harsh (the tongue test) and ensure they wash their hands very carefully afterwards. You may also want to put a bit of moisturiser on them afterwards, as handling soap for prolonged periods does make your skin dry.
This is not my normal recipe, but it was very easy to follow. I chose the orange and pumice flavour and texture to use as an after-gardening soap.