Speed up drying/curing time of CP soap?

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Kevin Dunn did a presentation in which he describes his research into what happens when soap is made with milk. The sugar (lactose) in goat milk chemically reacts with NaOH or KOH and changes color in the process -- that's why milk soap tends to be darker than the same soap made without milk. The protein (casein) only slightly reacts -- not enough to worry about. And obviously the milkfat (butterfat) reacts.

Dunn concluded that using reconstituted goat milk as a 100% replacement for water will raise the superfat by 4% to 6% due to the reaction of the lactose as well as milkfat with the NaOH. To compensate for this, since soap recipe calculators don't have a saponification value for actual goat milk, you could reduce the superfat % by that much. I calculated that the fat in full fat milk raises the superfat by about 1% if milk is substituted for the water, so the remaining 3% to 5% increase is coming from the sugar.

As to whether milk sugars or other sugars will cause the soap to volcano, that is not a problem in my experience, so I don't spend any time worrying about it. The volcanoes I've seen and heard about have been triggered by the use of fragrances that contain known accelerants (such as eugenol) or to slowly pouring cool lye solution into unusually hot fat or to heating soap batter on the stove top and not watching the temperature carefully enough.

As far as food and similar ingredients decomposing or otherwise going bad in soap, the high pH of soap will inhibit microbial decomposition if the soap maker is sensible. I've seen evidence of mold or other decomposition on soap in only a couple of instances. One was when a bar of soap at a sink was contaminated with stuff from a person's very dirty hands and the bar was left dirty, damp, and untouched for some time. Another was when the soap maker heavily sprinkled botanical/food ingredients like flower petals or oatmeal flakes on the top of the loaf. In both cases, the contaminated areas were ON the soap, not IN it. Food type additives have been used IN soap for centuries, including potatoes, starches, eggs, and dairy, so the idea is nothing particularly new or unknown. As IL points out, additives like these should be in small particles or liquids, not big chunks. They should be used in low to moderate amounts and mixed well into the soap.
 
Thank you DeeAnna...

Most people call it CPOP nowadays -- ITMHP is going to get you a lot of blank looks.

I'd also say most people here don't do the "170 degrees F for an hour" method anymore.

That much heat for that long often causes problems. Instead, preheat the oven to 120 to 140 F (some folks shoot for 110 F), turn the oven off, and then put your soap in the oven. Leave it in the oven for at least several hours. All you need is sufficient gentle warmth to encourage the soap to reach gel temperature.

CPOP isn't about "aging" the soap, and it's not the only way to accomplish the goal of gently warming the soap. You can often get similar results by using a heating pad, putting the soap in an insulated cooler, etc.

Avoid CPOP if you have a recipe you know will warm up well on its own -- recipes with added sugars or beer, or recipes with a lot of coconut oil are examples.

Yes, you can do CPOP in a cardboard mold although tape or glues may fail, especially if you decide to use the 170 deg F method.


Your explanations are one of the main reasons that I read thru all of the threads on a pretty regular basis. The above explanation is really clear and thorough, as are all of your explanations. Thanks for all of your contributions to this forum! :)
 
I can attest to the "don't cook at 170° for an hour" thing. I had a recalcitrant soap last night that, after an hour, wasn't reaching gel phase in the oven.

Being tired, and it being late, I heated the oven to 170°, left it go for 30 minutes, then turned the heat off. Gel phase commenced shortly thereafter. Boiling also commenced shortly after gel phase. Which was then followed by a severe loss of scent.

The soap is already unmolded and rock hard, but also has boil pockmarks. It's acceptable--barely--for gift-giving.
 
Thank you for the information, Deanna!

Now I'm a bit concerned about the oatmeal soap I made a few days ago. I don't want the oats in my soap to sour. I put in more than I usually do but I ground them up fine in my spice grinder.

Half of them sunk to the bottom in the thin CP soap,so there's a big chunk of them sitting on the bottom. I swear, I have had more problems with cool CP soaping! I am considering going back to cooking it all. Maybe I'll get a slow cooker just for soap.
 
In response to the topic... I once had to get a batch of soap made and shipped in a week. These were "Pass the Bar" soap favors to celebrate my nephew becoming a lawyer. My sister in Seattle asked and I was happy to oblige. The party was 2 weeks away.

Day 1: Make soap. CPOP (Cold Process Oven Process). Pre-heat oven to 170°F. Put soap in. Turn oven off. Leave in oven overnight.
Day 2: Unmold. Cut into bars. Allow 24 hours before next step.
Day 3: Grate it up. Rebatch in a SS pot, in 250°F oven for an hour. Mold it up. Leave it overnight.
Day 4: Unmold. Cut into bars.
Day 5: Rebatch again.
Day 6: Unmold. Cut into regular-size 5 oz. bars. Then cut those in half again to make 2.5 oz. bars.
Day 7: Wrap (in cigar bands that allow soap to breathe) and ship.

I used one of my favorite recipes -- plain Jane white bar -- nothing fancy, but lathers like a mad dog. I kept one bar to check its progress. It was smooth creamy white with no off-putting odor or blemishes at all. But I don't recommend this method to anyone -- it was a lot more work than I expected but fun to do and well worth the effort.
 
Thank you for the information, Deanna!

Now I'm a bit concerned about the oatmeal soap I made a few days ago. I don't want the oats in my soap to sour. I put in more than I usually do but I ground them up fine in my spice grinder.

Half of them sunk to the bottom in the thin CP soap,so there's a big chunk of them sitting on the bottom. I swear, I have had more problems with cool CP soaping! I am considering going back to cooking it all. Maybe I'll get a slow cooker just for soap.

I would just watch it. I use oatmeal finely ground or baby oatmeal in my soaps frequently and have never had them get moldy. I blend the oatmeal into my oils and stick blend them well before adding my lye. That way I know they are mixed I well.
 
They were finely ground and I put them in before stick blending. It might be ok. I'll see what it looks like after it's hard. I can always rebatch it but I'd rather not.

A friend in Ontario wants some from me for Christmas so I might cook it anyway so it's ready to send to her soon, maybe. I plan to make more shortly, so I might cook the new ones and leave the oatmeal as is...maybe. But then again, I'm not that happy with the oatmeal distribution so I might rebatch it. Ha! Ha! I'm great at making decisions. lol

If I can find a good slow cooker at the thrift store cheap I might buy it and just make all soap in it. It looks easy on the 'net. I have always cooked it in a pot on the stove but tend to over cook it. It would make rebatching easier too.

Anyone cook soap in a slow cooker?
 
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They were finely ground and I put them in before stick blending. It might be ok. I'll see what it looks like after it's hard. I can always rebatch it but I'd rather not.

A friend in Ontario wants some from me for Christmas so I might cook it anyway so it's ready to send to her soon, maybe. I plan to make more shortly, so I might cook the new ones and leave the oatmeal as is...maybe. But then again, I'm not that happy with the oatmeal distribution so I might rebatch it. Ha! Ha! I'm great at making decisions. lol

If I can find a good slow cooker at the thrift store cheap I might buy it and just make all soap in it. It looks easy on the 'net. I have always cooked it in a pot on the stove but tend to over cook it. It would make rebatching easier too.

Anyone cook soap in a slow cooker?

DeeAnna was talking about full oats being sprinkled on top of a soap being a possible problem. She was not talking about finely ground oatmeal added to a mix. Yours will be fine.
 
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Yep, Carolyn and Shari are right. Finely ground IN the soap should be fine. Whole oat flakes ON the soap -- not so good.
 
I have a bar that I have made for years that uses a large amount of whole oats with no issues. I never put any type of botanical's or large salt grains of top of soap for decorations. Never Never Never :). I usually use Oat Flour except in my DB soaps because men tend to like a bit scrubbier
 
If I can find a good slow cooker at the thrift store cheap I might buy it and just make all soap in it. It looks easy on the 'net. I have always cooked it in a pot on the stove but tend to over cook it. It would make rebatching easier too.

Anyone cook soap in a slow cooker?

For my all HP batches and any rebatches, I just use my oven (set to 180F/82C), and a stainless steel soup pot with a cover. Unlike the stovetop, the oven provides even heat all around, so there's no chance of the bottom scorching.


IrishLass :)
 
Now I'm a bit concerned about the oatmeal soap I made a few days ago. I don't want the oats in my soap to sour. I put in more than I usually do but I ground them up fine in my spice grinder. Half of them sunk to the bottom in the thin CP soap,so there's a big chunk of them sitting on the bottom.
I wouldn't worry too much about the chunk on the bottom -- you can always say you planned to make it that way! You know, a scrubby side and a smooth side to the soap. Sounds like a winner to me!

As Carolyn mentioned, I also prefer to use Oat Flour -- Bob's Red Mill from the grocery store or Whole Foods -- I add it to my warm oils, mix for 1 full minute, before adding the lye solution.

Picking up a slow cooker, or as it is more commonly referred to, a "crock pot", at a thrift store is a good idea. Get the largest one you can find cuz you need some head room for turning/stirring plus the soap can bubble up to the lid... and beyond ...the minute your back is turned!

You'll also want one with a removable insert so you can put it in the dishwasher. I found mine at a thrift store. It's a 6 quart Rival with a black ceramic pot insert. It's a good investment because you can also use it to infuse oils for herbal products; make liquid soap; etc. in addition to hot process hard bars.

Just a stab in the dark here, but I'd venture to guess that just about everyone responding on this thread has used a crock pot to make soap.
 
Thanks everyone for the information! I going to keep my eyes open for one at the thrift store this winter. I can use a pot on the stove, as I have done many times, but the crockpot method looks so much easier and safer.

Zany: Good idea. I think I will leave it as is, provided it still looks good when dry and works well. I'm too lazy to rebatch unless I need to. :)
 
As to whether milk sugars or other sugars will cause the soap to volcano, that is not a problem in my experience, so I don't spend any time worrying about it. The volcanoes I've seen and heard about have been triggered by the use of fragrances that contain known accelerants (such as eugenol) or to slowly pouring cool lye solution into unusually hot fat or to heating soap batter on the stove top and not watching the temperature carefully enough.

I want to also add some thoughts to DeeAnna's informative post what I have already learned from her and other's experiences over the past years.

I have never had a volcano in my soaping experience but I think that when we add at trace ingredients such as reactive sugars (fructose, lactose, maltose while table sugar is almost non reactive with NaOH) or fragrances that accelerate saponification, we encourage a volcano to happen.

Trace is a stage when saponification is at its very start producing heat and whatever reactive ingredient we add at that time we add more reaction and thus more heat and if we had already mixed lye and oils at a relative higher than normal temperature, then the total temperature of the mixture could possible activate a volcano.

So I always encourage new soapers to avoid adding anything at trace and instead they should add the reactive sugars (honey, fruit juices, milk, ect) at the very beginning at the lye solution or even better at water prior NaOH in a way that they will not be scorched.

That way the reactive sugars will free all the heating from their reaction just before the saponification starts.

People tend to add valuable ingredients at trace but we already know after Kevin's Dunn lab tests that at trace there is as much as 80-90% available NaOH to react with anything it can find on its way...

If for any coloring of fragrance purposes one must add a reactive ingredient just before molding the mixture, then it is a good practice to add it at full emulsification of oils and lye just as the member newbie has already shown here:

[ame]https://www.youtube.com/watch?v=39pLHKMtN6o[/ame]
 
Even in proper amounts, all sources of sugars (including milks, beer, wine, honey, fruits, vegetables, etc) can encourage volcanoes no matter when you add them in. That includes table sugar. You just have to know your recipe, know your fragrances, know your soaping temperatures, and watch it like a hawk to avoid a mess. I am not saying to never use sugars, I am saying use due diligence to avoid volcanoes.
 
Whatever you do, don't put them in a food dehydrator. I stupidly made the mistake of trying to speed the hardening time of some rebatch soap that I added too much liquid to by putting them in there. The whole house smelled great, since all the FO worked is way out of the soap, and they all warped shape. I'm certain it was the heat, not the airflow that was the problem. Anyways, don't be stupid and put them in a food dehydrator like me :)
 
Kevin Dunn did a presentation ... the contaminated areas were ON the soap, not IN it... They should be used in low to moderate amounts and mixed well into the soap.

Thanks for this very informative post, DeeAnna. By that token, can fresh orange zest be added at thin trace to the soap? If yes, is there a rule of thumb on how much is acceptable, and will it retain any smell at all, if I add a little arrowroot? I plan to mix the oils and lye solution at room temperature (about 72-75 degrees F) in the hope of retaining the fragrance.

The other question I have is a most basic one -- how does one figure out that a CP soap is actually cured? In an objective rather than subjective way, I mean -- for example, if my recipe is at 38% (and 2.7 x lye weight) and I use 228 grams water and 600 grams oil, and the wet soap mixture is about 910 grams, can I assume that my soap is cured when its weight (total of all the now cut pieces) reduces by about half the water weight (about 115 grams)?
 
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Fresh orange zest will rot inside of the soap. I bought some soap early in my soaping experience with some in it. At about 3 weeks after purchase, the bar had little rotten spots all in it, followed by a fine case of DOS.

If you make a batch of soap today, then another in 6 weeks, you could test them against each other and tell one is cured and one is not. Or you could test your batch weekly and see when the lather and overall quality stops improving. That is when your soap is cured. Far more is going on than moisture loss.
 
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