What is milk soap and why is it beneficial.
Milk soaps are so popular and with good reason. They are a truly luxurious , creamy soap and often revered by those with skin conditions such as eczema and psoriasis.
There are no restrictions on the kind of milk you can use. Goats milk is extremely popular and possibly the most common, particularly here in the UK but you can use any kind of milk including plant based, such as coconut milk.
Do all milks give the same result?
Well no, not necessarily. They will all generally contain proteins to one degree or another and fatty acids, some will have naturally occurring vitamin E and Omega 3 and various nutrients, others will be high in sugar. Animal derived milks will contain lactose and therefore lactic acid within which Alpha-hydroxy acid (AHA) is found. You may recognise AHA as something often found in cosmetic products for breaking down dead skin cells and brightening the complexion.
I won't be going down the route of extolling the virtues of one milk soap over another or making claims of what it can do for your skin care regime as to be quite honest, I don't have that knowledge and it is certainly not my area of expertise but I do love both my goats milk and coconut milk soaps and find they both have a lovely, creamy lather. I am fortunate that I do not suffer any skin complaints so I cannot comment from that perspective but my skin always feels lovely and soft and moisturised after using my milk soaps.
What kind of milk should I use for my soap making?
First and foremost your milk of choice will depend on your dietary preferences. If you are vegetarian or vegan then you will be looking for a plant based milk. Otherwise, you can also choose from a range of animal derived milks. The fat content is one of the most important factors as this contributes towards the overall feel of the soap.
As a guide goats milk has around 4% fat, cows milk is 3 to 4%. Make sure you choose the full fat versions and shake it well before you use it.
I have been unable to find a definitive fat content for coconut milk but it is without a doubt significantly higher, most sources state it is 21% to 24% but some state a whopping 50% fat. Wow - no wonder it makes a fabulous bar of soap ( and is also extremely calorific). I think the variation in % is down to the differing extraction plants and the fact there is no industry standard , or at least not a specific figure that has to be attained. The soaps below are my coconut milk pebbles which are coloured with activated charcoal and cocoa powder and which I teach in my milk soap classes.
By contrast, other plant based milks are made by grinding or extracting the nut or grain and then adding water. Some of these are extremely low in fat, rice milk has around 1% so I would be inclined to avoid that.
What I would say however is go with whatever is your preference, usually we replace some or all of our water with milk so whichever one you go with will give your soap that added boost.
How to make soap with milk?
You can use both the cold and hot process methods for soap making but as milk is quite high in sugars you need to keep it as cool as possible. Generally we freeze it before adding our sodium hydroxide to it. If you let it get too hot it will scorch and burnt milk smells awful. Don't let it gel, you could even pop it straight in the fridge after putting it in your mould to ensure this doesn't happen.
With hot process soap you would still use frozen milk but you would then cook on low, very slowly and make sure you melted butters and oils are at a low temperature too. It will take longer than usual and it may well still have an odd smell initially until you have added your essential oils.
If you would like to learn more about making milk soaps I run intermediate salt and milk soap classes in person from my workshop in Dorset and as live online Zoom tutorials also (basic soap making knowledge is required for both of those)