I’ve had many questions pop up in the last few weeks about making milk soaps, so today we are going to start a 5 post series for milk soaps using the Half and Half Method.
Preparing to add lye to water.
1) Calculate the amount of lye and liquid needed for the oils you plan to use.
Adding lye to the water.
3) Measure the lye and set aside.
4) Measure HALF of the needed liquid as water and set aside. Measure HALF of the needed liquid as milk and set aside. Milk should be room temperature, not frozen or heated.
Almost completely melted oils.
Adding the lye solution to melted oils.
7) Add fragrance. Pour into prepared SHALLOW molds (1 inch deep or so). Milk soaps can get very hot and shallow molds help the excess heat dump into the air. This will prevent the milk sugars from interrupting the saponification reaction.
This is called the Half and Half Method, because you use half water, half milk, and add the milk half way through the blending of the batch.
Collect needed items:
| Ingredients Hydrogenated Soybean Oil Coconut Oil Olive Oil Sodium Hydroxide Cows Milk Water |
Equipment Scale Soap Spoon Gloves Extra Large Square Tray Mold Square Tray Mold Immersion Blender |
| Time spent: Weighing time: 8 minutes Adding lye to water: 15 seconds, followed by 60 seconds of stirring Heating of oils time: 3 minutes Pouring lye solution into the fat mixture: 10 seconds Using immersion blender to mix soap solution: 90 seconds Adding milk to the batch: 20 seconds Using immersion blender to completely mix milk into soap: 40 seconds Pour into molds: 60 seconds Allow soap to rest: 24 hours |
| Recipe in ounces: 40 ounces weight Hydrogenated Soybean Oil 20 ounces weight Coconut Oil 20 ounces weight Olive Oil 11.1 ounces Sodium Hydroxide |
Tomorrow we will make a Goats Milk Soap. Later this week, we will make milk soaps with Buttermilk, Soy Milk, and Almond Milk.
Don’t forget to submit your blog or video posts to win the MMS Perfumer’s Kit. Remember, this kit is worth $280! Submissions are due by March 1st for posts during February.
 Mixing the oils to halfway to trace.  Adding the milk to the batch.  Pouring the soap into the Extra Large Square Tray Mold.  Filling a Square Tray Mold.  Ready to cut the soap. |
 The soap is almost ready for the milk.  Using the immersion blender to mix batch completely.  The Extra Large Square Tray Mold is almost completely filled.  Soap after 24 hours.  Pile of cut soaps. |
Thank you for this series. Is this raw cows milk you are using in this soap? Will you be addressing the types of milks that can be used (raw milk, low fat or whole milk from the store, organic milk, goat milk, cream, etc.)? I hear the name “goats milk soap” a lot. I also like the detailed photos throughout the process. That is really helpful. Thanks again for the great information. Emily
Emily,
I don’t have a cow, yet. 🙂 And in my state it is illegal to sell raw milk. So, this milk is from the grocery store section. It is 1%, I think. All milks will give a different color, but the process is the same. No adjustment in the lye, and follow the same key points and temperatures. You will be fine. At the end of the week I will show you a color comparison of the milk soaps. All milks will give a different color. You can even reconstitute dry milk powder.
I can’t wait to see the rest of the series on milk-based soaps! Do have a question – the only molds I have are the wooden ones I’ve made, “log” style and I see you use a flat tray mold; can I still use my “log” mold or will the soap be adversly affected by this style of mold? BTW after reading a gozillion “informative” soap making sites, getting A LOT of misinformation – I have to say your web site AND your technical support staff are THE most informed of all. I can’t say thank you enough! TY TY TY 😉
You can use the log style molds. Use the cooler temperatures and if you generally pour 3 inches deep, try a 2 inch pour. When we make milk soap we try to never go above 1″ deep. We do this so heat can’t build up in the mold. We want enough heat to make sure the reaction is complete, but we don’t want a run-away horse in temperature. The deeper your pour, the more likely you are to get the super hot temperatures. The more shallow you pour the soap, the less likely you are to get the volcano soap.
When people freeze their milk, they are slowing the reaction down at the beginning to prevent this same problem. The issue with freezing, is that we also stall saponification. I can’t tell you the number of people who call and say they can’t produce soap fast enough because they don’t have space for the “curing” of their soap for 5 to 6 weeks.
If we make soap this way, the Half and Half method, we won’t stall saponification AND we can get the soap dried out much sooner. It is a win for complete and safe soap, and a win for the production room which all equals a win for the bottom line!
I have talked to soapers who use goat milk to make soap and they put it in the oven to gel after they’ve poured it into the molds. How can they do that if milk soap is so prone to overheating?
I am not sure what they are doing. Is the oven on? Is it a “no drafts” location? Are the molds individual instead of a large mass? I don’t know. Please tell more.
I tried to use the half and half method today with almond milk. When I mixed the lye into the half water amount, after a bit there was a white film forming on the top of the water. At first I thought that my spatula was disintegrating into the water/lye mix. Now I’m thinking that the lye started to separate out of the mix. Is this possible? I went ahead and made the batch but I’ll definitely be ph testing before touching.
It is showing all of the minerals in your water. Your soap will be just fine.
Thanks!! I’m so glad I discovered this blog!!
As Cynthia says above, after reading NUMEROUS websites, blogs, & watching YouTube videos, your website has succinctly answered one of my 2 questions. The other is what about adding pureed fruit and using it in this Half & Half Method?
The problem with fruit is decomposition. The fruit will rot. I suggest using a teaspoon and making the soap as normal. If all is good then make another time and add 2 teaspoons.
I wasn’t able to rate this, but I give you 5 stars!
hi….
I have made a liquid cow’s milk soap .. but my soap does not last long ..
entering the third week of my soap has begun moldy … what causes it? and I expect natural remedies from you … thank you …
This means you have too much material in the soap, fresh fruit or some thing. Send us your ingredient list and your process and we will help you get this fixed.
wonderful soap , i aim for the same results the next time i’m making soap because the first batch i’ve made failed “undissolved lye ” ..but i need to ask : why do we need to heat the oils? should they be at a specific temp. before we add the lye?
Amalia,
We need the oils to be at least warm enough for our reaction to take place. I recommend having your oils and lye solution both around 110 F.
This way you are warm enough for saponification to occur without other issues from excess heat.
Taylor
Thank u Taylor