bar soap

Why We Lye

Why We Lye
If you've ever had anyone tell you they can make soap without lye, they're lying. Haha..sorry for the pun.

But in all seriousness you cannot make soap without sodium hydroxide, aka lye. You can use potassium hydroxide but that's for liquid soaps. Bar soaps must have lye. 

What you've probably heard and read about lye is true. It's very caustic. It will burn and cause problems if you're not handling properly. I've learned lessons the hard way because as we get more and more accustomed to doing something, we tend to shortcut and try to speed up the process. I've had lye splash in my eye, burn my arms and even my feet when wearing flip flops. Now I NEVER go without safety glasses or arm coverings. (I do still sometimes forget to change shoes though.)

You've probably heard the word 'Saponification' before and it's on my ingredient label. It simply means the process of turning lye into soap. Once the curing process (4-6 weeks) is complete, there is no lye left in the soap. Without getting too "sciencey" if that's a word, the molecules in the lye bind with the molecules in the oils and milk, in my case, to form a hard bar of soap. 

The main difference between using milk and water as the liquid is handling. Because the milk has sugar, it will tend to heat up extremely fast when the lye is added. This will cause the milk to essentially scorch and turn an unsightly shade of orange and therefore mess up the batch of soap. This is why I freeze my goat milk into cubes. The frozen milk will cause the lye to dissolve more slowly and avoid the scorching. 

So what you're left with is a moisturizing bar of soap and depending on the superfat level of your recipe, you'll have a wonderful cleansing and natural bar of soap. Superfat is another soapmaking term I will elucidate on in a future post. :)

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