This post is part of my series on making goat milk soap. You'll find the links to the previous posts at the end of this one.
Cold process and hot process begin the same way; in fact, you'd follow the instructions for making cold process soap up to the point of pouring the soap into the mold. That's where this post begins.
First, the legal stuff:
These are the safety procedures I use.
Please note that I am not responsible for accidents;
this post is for educational purposes only.
What additional equipment is needed to make hot process soap? A slow cooker. That's it. You might be able to find an older model at a thrift store or yard sale. I looked for quite some time but didn't find one, so I bought a new Crock-Pot (affiliate link) for my kitchen and dedicated my old one to soapmaking.
All right, let's begin at the end of the cold process post when the soap reaches "trace" - the raw soap thickens and turns opaque. Instead of pouring it into a prepared mold, I pour it into my old slow cooker. I plug it in, turn it on and set it on Low, put the top on and leave it alone.
I check on it every 15 minutes or so. As the soap cooks, it climbs up the sides of the slow cooker and sort of folds over on itself.
More and more of the cooked soap is visible, and the uncooked center gets smaller and smaller.
Eventually there's no smooth, uncooked soap left in the middle. This takes about an hour in my old slow cooker, which tends to heat up a bit more than more modern models. I stirred it up before taking the photo below.
The consistency is rather like waxy mashed potatoes. This is the time to add fragrance or essential oils if you're going to scent your soap.
The soap is spooned into the mold. There is no "pouring" of this soap, it has to be scooped up and plopped in the mold. Once it's all in, I do my best to pack it down and get rid of air bubbles. I gently bang the mold a few times on the table to help settle it in place.
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Any soap that was left in the slow cooker, on the spoon, or dropped on the top of the workbench has dried immediately. It's a good idea to cover your workspace with newspaper before this step.
Notice that the top of the soap in the mold doesn't have any resemblance to "smooth". It sets up really fast; there is no way to smooth it out.
As soon as the log of soap is hard enough, it can be removed from the mold and cut into bars. If you don't want this interesting-looking top on your bars, you'll need to cut the top off when you cut your bars.
It's unmolded and cut into bars in the same way as cold process; we'll do that in the next post. Hot process soap doesn't need to be cured as long as cold process soap. It's ready to use in about a week, but it will be harder and longer-lasting if it cures for a longer period of time.
I prefer not to go through this extra step and I usually stick to the cold process method, but hot process does have its place if you're in a hurry. Which method would you prefer?
You'll find all of the items you need to make soap in my Amazon storefront, where you can browse the items I use every day plus some fun and functional items that I'm sure you'd love to have as much as I would!
In this series:
What You Need to Make Goat Milk Soap
How to Measure Oils for Soapmaking
Making Soap with Goat Milk: Cold Process
Making Soap with Goat Milk: Hot Process
Making Soap with Goat Milk: Unmolding, Cutting and Curing
