So as you know, I’m a sucker for a good soap recipe. I’ve made a lot of cold process soap, which is kind of my go-to really. But I wanted to show you how hot process soap works, because there are a couple of advantages to HP recipes over CP soap.
It can take a little longer to master, but stick with it because you might actually prefer this method!
Hot process soap, also known as crockpot soap, will produce a wonderful, luscious soap that is infused with the gorgeous aroma of sweet orange essential oils. It smells so good I almost wanted to take a bite out of it, but don’t do that because that’s just crazy talk.
Sweet orange essential oil is one of the lowest costing essential oils on the market, so don’t worry too much about breaking the bank on a failure if this doesn’t work quite right the first time around. You absolutely can substitute it for fragrance oil if your prefer.
Making Hot Process Soap
Hot process soap can be a little trickier, mostly because you’ve gotta keep your eye on it. However, the main thing I love about it, is that it’s just so much quicker than cold process. There is no waiting 4 weeks for it to cure. Within a couple of days your gorgeous soap is ready to use or even gift!
The application of heat makes the difference here. Nevertheless, this means you’ve gotta keep a watch for up to an hour as it cooks in your crock pot. As I’ll discuss later, you can use a timer to make this a little easier on yourself.
It’s also much hotter and firmer when you pop it into the mold, so you’ve gotta be prepared to work even quicker and more carefully than you with cold process. It’s also worth mentioning that this soap can be a little soft for up to a week after you cut your slices. If this bothers you, make use of the sodium lactate to harden up your soap much faster.
I’ve estimated it can take you up to an hour and a half, maybe even 2 to get this recipe right. So make sure you’ve cleared your morning or afternoon schedules to accommodate for this. While this recipe doesn’t really require a crockpot, I find it’s just so much easier than doing it on the hob. These days they’re not really that expensive, and you can find one for a very reasonable price on online.
But let’s take a look at the ingredients and equipment you’ll need to whip up this fabulous crockpot soap.
Sweet Orange Hot Process Soap (HP)
- 400g Olive Oil
- 200g Peach Kernel Oil
- 200g Castor Oil
- 100g Coconut Oil
- 40 mls Sweet Orange Essential Oil
- A few drops of Orange Soap Dye
- 120g Sodium Hydroxide (lye)
- 297g Distilled Water
- 3tsp Sodium Lactate (Optional)
- Measuring Jug
- An assortment of Spatulas and Spoons
- Stick Blender
- Soap Mold
- Personal protective equipment (Glasses and Gloves as a minimum)
Gather all your ingredients and equipment, taking the time now to weigh out everything you’ll need. It just makes everything so much easier later on when you need to work quickly.
This recipe has been calculated so that it works properly, so be quite strict with your measurements. Be especially strict with the amount of lye you’re using.
Switch on your crock pot to a Low setting and place all of your oils into the pot. You want to leave this to melt (as coconut oil is a solid at room temperature).
Make sure to exclude your essential oils and the soap dye, we’ll be using this later on.
While your coconut oil melts into the rest of your oils, pour your sodium hydroxide into the water, creating your lye solution. Give it a bit of a stir so that it dissolves fully into the water. Never pour the water into the lye to minimize possible splashing.
Wear your personal protective equipment for this step, just to be safe. You’ll either want to pop it outside or place near an open window to allow the fumes to ventilate.
If you have kids about, make sure your little ones can’t get to this as even a little can burn intensely. If this is a concern, set them up in a different room with cartoons or coloring, far away from your crafting space. Better to be safe than sorry.
Once your solid oils have melted, compare its temperature to the lye solution. While I find balancing is much less of a problem for the hot process soap method, you don’t want your lye solution to have completely cooled. aim for around 130 to 110f.
If you’re planning to use the Sodium Lactate, add it to the lye when it’s temperature drops below 130f and give it a good stir. This is the best way to get it into your soap.
Once you’re ready, turn your crock pot off and pour a little of the lye into your oils and give it a stir. Make sure you’re wearing your personal protective equipment. If you see little or no reaction, go ahead and add the rest of the lye.
Give the oil and lye solution a good mix with a spatula or spoon.
Now we need to get the batter to a light trace. While it’s possible to do this next step by hand, it’s much much easier and quicker to do this with a stick blender. You’ll want to blend your batter in short bursts, stirring each time you stop blending.
Keep going until you reach ‘trace’. You’ll know when you’re there when the consistency of the batter changes. You should be able to run a spatula across the top and it leaves a nice trace behind it, or if you pick some up with a spoon and let it drip back onto the surface of the batter it shouldn’t sink in straight away.
I’d say this process will take about 2-3 minutes, but this can vary depending on the temperature of the oils or even the temperature of the room you’re working in. So just watch for a change in consistency.
Now that we’re at trace, we need to reapply the heat. Turn your crock pot back on and put it on a low setting. You’ll also need to pop the lid on so minimal heat can escape.
You’ll now want to leave your batter to ‘cook’ for anywhere from 40 minutes to 1 hour, stirring in intervals. I like to set my timer for 20 minute intervals, returning to stir it up when the buzzer goes. Make sure you’re wearing your glasses and gloves when you stir.
Don’t be alarmed if your soap better changes quite dramatically during this period. When you return to it, it’s totally normal for it to look a bit weird and foamy like it does in my picture below. Just stir the foam back into the batter and leave it for another 20 minutes.
After about 20 minutes to half an hour, your soap should begin to look a bit like apple sauce. I call this the apple sauce phase, as it really does look a bit like stewed apple. This is fine and totally normal, just give it a good stir, replace the lid and set the timer for another 10 to 20 mins.
When your batter starts to look more translucent, almost like Vaseline, you’re pretty much done with the cooking stage, so turn off the heat and give it another stir. This is called the ‘gel phase’, which is a phase that your cold process soap would go through on its own, under all those towels and blankets over a 24 hour period.
A good test to see if your soap is ready is to scoop out just a smidge and leave it to cool on a plate. After a minute, roll it between your fingers. If it feels greasy or leaves some kind of an oil trace, leave your batter for another 5-10 minutes to cook a little more and then test again.
When I made this recipe, it took about 50 minutes to get it to gel phase, but keep going for up to an hour if you need to. It is possible to burn the soap during this period, so make sure you keep your eye on it, or be strict with yourself when that 20 minute timer goes off.
When you’re not stirring, this is a perfect time to get on with any clean up that can be done, or even weigh out your essential oil or fragrance oil so you’re ready for the next few steps. If you won’t be using a silicon mold, also use this time to line your mold with some baking parchment.
If you want to make use of a soap dye, now is the perfect time to mix it in. Add a few drops at a time and stir until you reach a desirable color. Remember that your soap will darked once it hardens in the mold, so be conservative with your dye.
Now add your essential oil or fragrance oil, stirring well once you’ve poured it in. Make sure you do this relatively quickly, as the batter will continue to cook even though we’ve turned off the heat.
Now we need to get it into the mold, and work relatively quickly but also carefully. Pour your batter into your pre lined or silicon mold, being careful not to spill any. If your soap has gone a little bit over, you can use a spoon to shovel it into the mold.
If your mixture isn’t particularly level, you can give it a bit of a bash to level it out some. You could also try using a spoon or spatula. I find it extremely difficult to get a smooth surface on hot process soap, and I’m definitely not alone in this.
I tend to just embrace it and use a fork to make some interesting peaks. It makes the soap look wonderfully rustic, and also makes it look like you did it on purpose.
You’ll want to leave your soap for 24 hours to harden up in the mold. After this, remove it and leave for a couple more days, which should be long enough for the soap to dry out a bit. The last thing we want is a sloppy soap.
And the final step is to cut your soap! You can use either a standard knife or a cool patterned cutter that is designed to give your soap an interesting texture. Either way, this soap should look great, smell amazing and feel absolutely fabulous on the skin!
While this method can be trickier than the standard cold process, I absolutely love how this soap turned out. You’ve just gotta keep your eye on it, and you should be absolutely fine. You might need to give this a few tries first before you’re more confident, but this is totally normal. I think I made this maybe 3 times before I got a good result.
Feel free to experiment with different ingredients. I definitely recommend making use of a lye calculator to make sure you get the quantity of water right, as that can make or break your soap.
Although the soap is safe to use a few days after making it, I found that leaving it to cure for a week or two does result in harder milder bars.
This makes a perfect gift for a friend or loved one, but you can also use it just to spoil yourself. It’s quite a luxurious soap, and everyone needs a pampering from time to time.
So I hope you’ve enjoyed reading my new homemade soap recipe! Give it a go yourself and let me know how you got on in the comments section below. Also share on social medias to spread the word that hot process soap is just as cool as cold process!
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