Hot process, refined vs unrefined, optimal temperature, lye resistance

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Druantia

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Hi,

I'm about to make my first batch of soap and I would have some questions to which I did not find many answers.

  1. Does it matter whether I use refined or unrefined oils? (not for superfatting)
    My understanding of what really matters here is the ratio of the different fatty acids in oils and fats. Does the fatty acid ratio differ in the case of refined and unrefined oils?
    I would use unrefined oils only for superfatting (only if it doesn't have too strong smell)
  2. Material of Crockpot
    All crockpot has a ceramic inner bowl. Is ceramic resistant to alkalis? Can lye eat through ceramic over time? I see everywhere people using it, but I have concerns about it.
  3. Optimal temperature range for hot process
    What is the optimal temperature range for cooking soap? Slow cooker's low setting can vary a lot from brand to brand. Is 80-90C (176-194F) considered a good range?
  4. Almost every youtube video and article is about cold-process, but doesn't hot-process superior?
    I read many advantages of the hot-process (more stable and stronger essential oils, shorter curing time, controllable superfatting, etc...)
    Meanwhile, the only upside of cold-process is that the outcome is prettier which is not a priority for me.
    Isn't hot-process considered a much better, advanced technique? Why most of the tutorials, videos, and articles is about cold-process?
Thanks! :) :)
 
I can only answer the first question - unless it's for label appeal I would buy the cheapest version of oil available. For OO - extra virgin may be great for haute cuisine but it's not necessary ( and very expensive) to use in soap. The fatty acid profile remains the same which ever you use.
I don't consider hot process more advanced - but you will need to ask an expert there. I only do cold process because I don't like the rustic look of hot process.
 
I agree with @KiwiMoose that using unrefined oils is primarily for label appeal. Refined oils will often give you a lighter colored soap, where as unrefined oils (EVOO, for instance) can really change the final soap color.

Hot process is not a "more advanced technique" than cold process. It does have the advantage that the soap is fully saponified when it goes into the mold, but hot processed soap still needs to cure just as long as cold processed soap. Just like cold process, without 4-6 weeks of curing time, your hot process soap will melt away quickly in the shower, and will be more harsh on the skin. After a good cure, the bars will last longer and be more mild on the skin.

Many people enjoy cold process because they can make more intricate designs, and they don't have to stand over a hot stove or crockpot to watch the soap cook. Thus, making CP soap is much less time-consuming than HP, and uses less utilities. That being said, many CP soapmakers do "cook" their soap after pouring it in the mold, by putting it in the oven or on a heating pad. That ensures it is fully saponified within 24 hours and also safe to use at that time. But again, all soap needs to cure if you want it to be ideal, as opposed to merely "safe to use."

I'm not against hot process - that's how I made soap for the first 5-6 years. It does require less fragrance, and the fragrance can last a bit longer. It's also nice for using "naughty" fragrances that would cause acceleration or ricing in cold process soap. Still, I've gradually moved away from HP and do mostly CP today. It really is much more convenient, and the bars come out looking much more smooth and pretty, even without fancy designs. Hot processed soap almost always has air pockets inside and uneven spots on the top.

After weighing all the pros and cons, you should make whatever type of soap you like to make. And when you do, we hope you will share pictures with us!
 
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Thank you both for the advice!
The heating pad or the oven seems a nice combination of the two methods.
Maybe what concerns me more is that the lye somehow disintegrates the essential oils, but I will put it to test.
I will try several recipes both with CP and HP, I'm curious about how much difference will be in design, smell, and texture.
And yes, I definitely will document it and I'll be back with some pictures and my experiences!
 
Hi,

I'm about to make my first batch of soap and I would have some questions to which I did not find many answers.

  1. Does it matter whether I use refined or unrefined oils? (not for superfatting)
    My understanding of what really matters here is the ratio of the different fatty acids in oils and fats. Does the fatty acid ratio differ in the case of refined and unrefined oils?
    I would use unrefined oils only for superfatting (only if it doesn't have too strong smell)
  2. Material of Crockpot
    All crockpot has a ceramic inner bowl. Is ceramic resistant to alkalis? Can lye eat through ceramic over time? I see everywhere people using it, but I have concerns about it.
  3. Optimal temperature range for hot process
    What is the optimal temperature range for cooking soap? Slow cooker's low setting can vary a lot from brand to brand. Is 80-90C (176-194F) considered a good range?
  4. Almost every youtube video and article is about cold-process, but doesn't hot-process superior?
    I read many advantages of the hot-process (more stable and stronger essential oils, shorter curing time, controllable superfatting, etc...)
    Meanwhile, the only upside of cold-process is that the outcome is prettier which is not a priority for me.
    Isn't hot-process considered a much better, advanced technique? Why most of the tutorials, videos, and articles is about cold-process?
Thanks! :) :)
Although, people someone correct me if I'm wrong, but I don't think you [edit: fully] control which oil(s) will remain as the superfat anymore with HP than you do with CP [edit: even if you all the SF oils to the soap after the HP cook is done]?
 
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Although, people someone correct me if I'm wrong, but I don't think you control which oil(s) will remain as the superfat anymore with HP than you do with CP?

Unless you add it after the cook is finished?
That's right, you add the oils after the cooking process, when all the lye reacted. You are not able to do that with CP.
 
That's right, you add the oils after the cooking process, when all the lye reacted. You are not able to do that with CP.
I knew about this, but remember reading somewhere on this forum that even if you add the SF oils at the end to the fully cooked HP soap you still didn't have full control over which oils remained as the SF... Guess my memory is playing tricks on me.

@Dawni ?
 
Although, people someone correct me if I'm wrong, but I don't think you control which oil(s) will remain as the superfat anymore with HP than you do with CP?

Unless you add it after the cook is finished?
But honestly, after I've done quite a few batches now, I don't think there would be too much of a difference. I equally enjoy both methods, although I think HP is less messy, the cleaning after the soap-making is also easier. And if you play with the recipe and use the right additives, temperature, etc, HP could result in the same nice and clear appearance.
Most of the people use waaaay too much heat. Forget about the slow cooker, the bubbling, boiling soap that makes vulcanos. If you see any of these, you use too much heat. A double boiler is the way to go, despite you will see slow-cooker in almost every video and book.
Look at this video - how beautiful, controlled, and clean the HP really is. (I recommend you to watch the whole video btw., it's quite meditative. :) )
 
On cold process I always add my EOs to the fats before the lye.

When I first started i used to worry about the lye monster eating my precious EOs, but my life got soooo much easier when SB told me she doesn't do it that way.

It's difficult to get EOs fully mixed into already lightly traced soap before the EO accelerants cause the soap to sieze prior to my getting a smooth pour into the mold.

I prefer stickblending EOs into the oils immediately before adding lye solution. The scent survives the lye just fine and I don't have to be nearly as careful; adding EOs after trace to cp soap is like heart surgery to me...
 
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I use HP if I’m concerned about the fragrance.

I get distracted when I’m making HP in the crock pot… I haven’t quite figured out if it’s done for sure (does it look like Vaseline? Is it getting dried out?) so it’s all a little more stressful than I like. I just don’t enjoy it as much.

I’ve been making my HP in a crock pot that was already imperfect - there are a couple bumps on the bottom where the glaze is chipped off. It’s black and isn’t quite so shiny inside after a few batches of HP, but it’s holding up. With ceramics the glazing can “craze” (develop a lot of tiny cracks) and it hasn’t done that yet. I had a crock pot develop a crack and you either get a replacement or use a liner. I thought about trying to use a liner with HP since I have some around, but I haven’t dared.
 
I’ve used the same ceramic inner bowl for HP for about 6 years now and it’s still good. Just make sure there is no coating or paint on the bowl. I used one once a long time ago that had a coating on it, and the coating came off because of the lye.

176-194 F is a good range. I keep a meat thermometer in my crockpot and will adjust the crockpot setting as needed. With my formulas, I know if the temperature reaches 210 it will volcano.
 
Thank you both for the advice!
The heating pad or the oven seems a nice combination of the two methods.
Maybe what concerns me more is that the lye somehow disintegrates the essential oils, but I will put it to test.
I will try several recipes both with CP and HP, I'm curious about how much difference will be in design, smell, and texture.
And yes, I definitely will document it and I'll be back with some pictures and my experiences!
I only use essential oils and only make cold process. There is a separate sub-forum here about them and worth reading. There are blends that last longer than others. I have soaps that still smell great after 12 months, some even after 24 months. I'll be impatient for photos. Good luck!
 
  1. Does it matter whether I use refined or unrefined oils? (not for superfatting)
    My understanding of what really matters here is the ratio of the different fatty acids in oils and fats. Does the fatty acid ratio differ in the case of refined and unrefined oils?
    I would use unrefined oils only for superfatting (only if it doesn't have too strong smell)
  2. Material of Crockpot
    All crockpot has a ceramic inner bowl. Is ceramic resistant to alkalis? Can lye eat through ceramic over time? I see everywhere people using it, but I have concerns about it.
  3. Optimal temperature range for hot process
    What is the optimal temperature range for cooking soap? Slow cooker's low setting can vary a lot from brand to brand. Is 80-90C (176-194F) considered a good range?
  4. Almost every youtube video and article is about cold-process, but doesn't hot-process superior?
    I read many advantages of the hot-process (more stable and stronger essential oils, shorter curing time, controllable superfatting, etc...)
    Meanwhile, the only upside of cold-process is that the outcome is prettier which is not a priority for me.
    Isn't hot-process considered a much better, advanced technique? Why most of the tutorials, videos, and articles is about cold-process?
Thanks! :) :)
1) It's a matter of personal preference. I use Extra Virgin Olive Oil to cook with, but I use regular Olive Oil for soap making. I like the smell of 'raw/natural' cocoa butter and shea butter. The only time I use a 'refined' Cocoa Butter is for certain FOs that don't go well with Cocoa Butter. And honestly, using ANY expensive oil/butter in soap is a waste of money unless you are going to label appeal.

2) From what I have seen from folks who use crock pots for soap making is that the heating element will fail before the ceramic does. And from a conversation with @DeeAnna, the ceramic doesn't absorb anything so you could use the crockpot to cook in. Speaking solely for myself, if I did HP on a regular basis I would use a separate crockpot just because I like not having to worry about if something is clean or dirty when I got to soap or if I'm being lazy, I can let me soaping equipment hang out for a few days.

3) My understanding is anywhere between 165F to 200F.

4) It's a matter of personal preference; no one process is 'better/superior' to the other because the end results are the same...soap. There are Pros and Cons to both Hot Process and Cold Process. With HP you can have 'soap' in just a few hours; with CP it takes 24-48 hours before the soap is fully saponified. Yes, you can control your SuperFat in HP as opposed to CP because the SF is added AFTER the batter has saponified. I don't know about EOs...seems to me that the same rules would apply.

There is NO shorter curing time with HP...that is a lie; it's an excuse that greedy folks use to sell bad soap quicker. Whether saponification takes place within four hour or twenty-four hours, the outcome is exactly the same...soap. And soap NEEDS to cure. It BEGS to be cured. Now there is a whole bunch of magic (okay...it's science) that takes place during the curing process. One part of the curing process is water evaporation...which leads to a harder and longer-lasting bar of soap. The other part of formation of the crystalline structure...which leads to a gentler bar of soap, and often more bubbles and lather. If you have any doubts...take a freshly bar of soap and wash your hands with for a day...then wash your hands the next day with a bar of soap that has cured for six weeks...there is a WORLD of difference.

My personal preference is for Cold Process...takes me 30 minutes to whip up a batch of soap and clean up and then I can do other things while the soap is sitting in the garage. In fact, in the time it takes a lot of folks to make a batch of HP soap...I can make several batches of CP. Given that I wait eight weeks for my soap to cure...waiting one day doesn't make a difference.

If you need to make more soap, then buy more molds. Don't skimp on the process. Badly made soap reflects badly on ALL soap makers.
 
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