Hot processed versus cold processed in terms of curing

[Jen74]

Hey everyone,

So I have made so far 2 batches of soap in the last few months. Still kind of a beginner on all of this. My question is, When I made the soap, I used a pot to heat up the stuff until it became like a thick pudding before putting it into molds. I am guessing this is considered the hot process am I correct? My next question is, how long does hot processed soap take to cure versus cold process soap? I have been letting my soap sit for 6 weeks before using it. I just read somewhere that hot processed soap will completely cure very quickly though, that it is the cold process soap that is never heated that takes longer( 6) weeks to fully cure and be mild. Is this correct? How long does it take for hot processed soap to become mild and go fully through the saphonification process to where it is ready to use??

 

[Arimara]

Hey everyone,

So I have made so far 2 batches of soap in the last few months. Still kind of a beginner on all of this. My question is, When I made the soap, I used a pot to heat up the stuff until it became like a thick pudding before putting it into molds. I am guessing this is considered the hot process am I correct? My next question is, how long does hot processed soap take to cure versus cold process soap? I have been letting my soap sit for 6 weeks before using it. I just read somewhere that hot processed soap will completely cure very quickly though, that it is the cold process soap that is never heated that takes longer( 6) weeks to fully cure and be mild. Is this correct? How long does it take for hot processed soap to become mild and go fully through the saphonification process to where it is ready to use??

The blue is a very common misconception about hot process. A lot of those people writing blogs and cheap-overpriced books on soap making believe and spread this misconception too. Hot process soaps can sometimes need a longer cure than cp soaps because they need a bit more water when you make them. so if your recipe needs 6 weeks to cure, if you prepared it via hot process, depending on how you did it, it could take the same six weeks or longer.

The reason people think Hot preocessed soaps is cured out of pot is bcause they don't know the difference between saponification and cure. The two processes are not the same. Saponification is when the oils are being changed by the active lye until there is no more lye to react to your oils. Cure is often likened to the fermentation since it is through that process where soap gains their characteristcs as per your recipe. the longer you cure, the better your soap should be (unless your recipe was poorly formulated).

 

[Bladesmith]

Yes, you are doing hot process.

As far as curing, I would say that both hot process and cold process are about the same (and length depends on your soap and oils you used). The main difference is that with hot process, the soap is fully saponified when going into the mold and could, theoretically, be used immediately. Whereas with cold process, the saponification happens over the course of a few days and you could burn your skin if you tried to use it too soon.

Once both are fully saponified, it is a matter of waiting for soap to do it's thing.

 

[shunt2011]

I echo the others. CP & HP both need a good cure. Sometimes HP needs longer as more liquid is used to make it than CP.

 

[Jen74]

Thank you for the replies. This is The recipe I used and I made 2 pounds using the HP using these ingredients. I am highly sensitive so this concotion seems to work for me.

Water: 9.18 ounces
Lye: 4.52 ounces
oils: 32.00 ounces in total

This is a breakdown of the oils and amounts below are what I use according to SoapCalc.

Palm Kernal oil: 6.40 ounces
palm oil: 25.60 ounces
Glycerin: 1.6 ouces

I have left it cure for about 7 weeks. Does it need to cure longer than this?

 

[amd]

Why are you adding glycerin? Glycerin is a by-product of soapmaking so your soap will have glycerin naturally.

As far as water content, it looks like you used a standard amount (33% concentration) so a normal cure time would be expected. Although... I will say that when I have done HP with 35% concentration it seemed to take twice as long to get the HP soap to feel the same as the CP soap, but it's been a handful of years since I did HP so maybe my experience would be different with the recipe I use now.

 

[shunt2011]

A 6 weeks cure should be adequate for your recipe. I too wonder why the glycerin? Also, what made you decide on that recipe? It's a bit odd. But if it works for you that's all that matters. And it should move fairly quick as you've got no liquid oils in there.

 

[jcandleattic]

I also agree with the others, especially what Arimara said here.

difference between saponification and cure. The two processes are not the same.

Technically once saponification is complete you can safely use your soap from either cold or hot process, however, it will be harsh and drying until the cure is complete.
HP will feel a little milder a little sooner than CP, but that doesn't mean it's completely cured. My recipe, once it's completely cured, I can't really tell by feel which one is which. Only by the look of the bar. The HP bar might yield a better lather, however the actual feel of the bar is the same (if using the same recipe that is)

 

[Jen74]

I also agree with the others, especially what Arimara said here.

Technically once saponification is complete you can safely use your soap from either cold or hot process, however, it will be harsh and drying until the cure is complete.
HP will feel a little milder a little sooner than CP, but that doesn't mean it's completely cured. My recipe, once it's completely cured, I can't really tell by feel which one is which. Only by the look of the bar. The HP bar might yield a better lather, however the actual feel of the bar is the same (if using the same recipe that is)

IS there a specific way you can tell when your soap is completely cured? Like what does it look like? I have let mine sit for about 7 weeks now so I think it should be cured. It is more soft though after it gets wet. It does lather, but is still on the softer side. That might be normal though. I was just wondering if there is a way to tell when a soap is completely cured or not??

 

[jcandleattic]

IS there a specific way you can tell when your soap is completely cured? Like what does it look like? I have let mine sit for about 7 weeks now so I think it should be cured. It is more soft though after it gets wet. It does lather, but is still on the softer side. That might be normal though. I was just wondering if there is a way to tell when a soap is completely cured or not??

Not really, other than how the bar feels at weekly intervals. Take a small sample size and use it every week and test how it feels. Once it starts feeling the same each time you use it (much more mild, harder and the sliver will last longer) then a cure is achieved.
I"m not sure if it being on the softer side is normal or not for your bars, as I've never used your recipe.

 

[amd]

I have let mine sit for about 7 weeks now so I think it should be cured. It is more soft though after it gets wet. It does lather, but is still on the softer side. That might be normal though. I was just wondering if there is a way to tell when a soap is completely cured or not??

I wonder if the added glycerin is what is making your soap soft? With all hard oils, your soap should be reasonably hard. Maybe define what you mean by "soft after it gets wet" and "on the softer side". Like can you press it and leave finger dents or is it normal "Oh this soap is being used and dissolving" soft? Once the wet soap dries out, does it return to its former hardness?

 

[Jen74]

I wonder if the added glycerin is what is making your soap soft? With all hard oils, your soap should be reasonably hard. Maybe define what you mean by "soft after it gets wet" and "on the softer side". Like can you press it and leave finger dents or is it normal "Oh this soap is being used and dissolving" soft? Once the wet soap dries out, does it return to its former hardness?

Like for instance, today I just used a bar that I made back on April 5th. So it has been seven weeks curing. It is hard, but after I used it to shower, It does seem more soft now. I mean it is still hard, but if I press hard enough I can push it in in a spot. I notice these bars do not last a long time either. I think maybe that is because of the oils used? Not sure.

 

[Misschief]

One of the things that helped me get to know my soap when I first got into it (seriously into it) was to weigh my soaps on a daily, then weekly basis. As soap cures, water evaporates from it. In the early days, you'll see daily weight loss and then it starts to slow, usually at about the 4 week mark. It will continue to lose weight for some time but once that weight stabilizes, I consider it ready for use. Generally speaking.

 

[Jen74]

One of the things that helped me get to know my soap when I first got into it (seriously into it) was to weigh my soaps on a daily, then weekly basis. As soap cures, water evaporates from it. In the early days, you'll see daily weight loss and then it starts to slow, usually at about the 4 week mark. It will continue to lose weight for some time but once that weight stabilizes, I consider it ready for use. Generally speaking.

So here is a couple pictures of my soaps below....

 

[Jen74]

So here is a couple pictures of my soaps. I notice on one of them there was this werid dry spot. This happened pretty quickly after I made them( like the second day). It is like on the surface, you can scrape it away. Has this ever happened when you made soap? This was HP made... I will try and attach the
Pictures.

 

[jcandleattic]

Looks like ash, especially if you can scrape it off, but weird it's in a circular spot like that.

 

[Jen74]

Looks like ash, especially if you can scrape it off, but weird it's in a circular spot like that.

What is ash? I mean is this something that soap does?

 

[Bladesmith]

What is ash? I mean is this something that soap does?

Ash is something that forms when active lye comes into contact with the CO2 in the air. This is not something that usually happens with hot process since the lye should be pretty much gone by the time you put it in the mold. It is something that frequently happens in cold process soapmaking though.

That is pretty odd to have a spot like that. I only do hot process and I've never seen anything like that. Maybe someone else can come up with an idea of what's happening.

 

[jcandleattic]

This is not something that usually happens with hot process since the lye should be pretty much gone by the time you put it in the mold.

It sounds to me that while, technically the OP did a form of hot process, it didn't cook it fully through saponification. That could be why there is a little bit of ash.
Ash is as @Bladesmith said, but mainly is technically harmless. It's mostly and aesthetic problem.

 

[jangmb]

The blue is a very common misconception about hot process. A lot of those people writing blogs and cheap-overpriced books on soap making believe and spread this misconception too. Hot process soaps can sometimes need a longer cure than cp soaps because they need a bit more water when you make them. so if your recipe needs 6 weeks to cure, if you prepared it via hot process, depending on how you did it, it could take the same six weeks or longer.

The reason people think Hot preocessed soaps is cured out of pot is bcause they don't know the difference between saponification and cure. The two processes are not the same. Saponification is when the oils are being changed by the active lye until there is no more lye to react to your oils. Cure is often likened to the fermentation since it is through that process where soap gains their characteristcs as per your recipe. the longer you cure, the better your soap should be (unless your recipe was poorly formulated).

absolutely yes.