soap warming up after its been cut.

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candicec003

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So, I've made 10 logs of soap in the last week or so and out of 10 a couple of them have warmed up after I've cut them. Its so weird. Why? I soap at a cooler temp like 83°f to avoid gel phase, I put it in the freezer for the first few hours then move it to the fridge over night. In the morning I take it out and let it sit a room temp for the entire day and cut in the early evening. One of the soap recipes I used was coconut milk and water for the liquid. The other recipe that also warmed up was a chamomile tea for liquid and chamomile infused olive oil. After i cut the coconut milk batch I noticed it warming less than an hour later, and the chamomile soap started to warm the next morning.
Does anyone have some insight as to why my soap is warming up after being cut? They are kept in a cooler well ventilated area as well.
 
You are not alone! Although I have never had this happen myself (because I gel pretty much all my soaps), I have heard of this happening to several other soapers from time to time....... usually with milk soaps that they have stuck in the freezer.

Hopefully some of them will chime in soon.


IrishLass :)
 
I don't have personal experience with this phenomenon. However, it sounds like the soap wasn't done saponifying. There's probably active lye still in the soap, and as it comes to room temp the lye and oils can finish reacting. That would explain the heat, since saponification is exothermic reaction. It may need an extra day or two to saponify chilled.
 
So, I've made 10 logs of soap in the last week or so and out of 10 a couple of them have warmed up after I've cut them. Its so weird. Why? I soap at a cooler temp like 83°f to avoid gel phase, I put it in the freezer for the first few hours then move it to the fridge over night. In the morning I take it out and let it sit a room temp for the entire day and cut in the early evening. One of the soap recipes I used was coconut milk and water for the liquid. The other recipe that also warmed up was a chamomile tea for liquid and chamomile infused olive oil. After i cut the coconut milk batch I noticed it warming less than an hour later, and the chamomile soap started to warm the next morning.
Does anyone have some insight as to why my soap is warming up after being cut? They are kept in a cooler well ventilated area as well.

I believe tigersis is spot on. A soap that's kept warm after trace will take about 4 hours to finish saponifying. If you put it in the freezer and the fridge, you are slowing the reactions to a crawl. A better way to avoid gel is to decrease water. I don't know how alternative liquids might affect this, but with just water and a 40% lye, you could even cpop the soap and it won't gel.
 
Even soaps made at room temp will go through gel stage, my luck with preventing gel hasn't been good, when I froze my soaps, after I thawed them they would still go through a gel stage heating up. when I left it in the refrigerator without freezing, it would give me a partial gel.
 
Nature's Garden, Lilly of the Valley is hateful and will do this. I had that puppy on molded and the next day it decided to heat back up. Thankfully it was sitting on a plastic tub lid. Very messy...
 
Even soaps made at room temp will go through gel stage, my luck with preventing gel hasn't been good, when I froze my soaps, after I thawed them they would still go through a gel stage heating up. when I left it in the refrigerator without freezing, it would give me a partial gel.

How long were you leaving them in the freezer? Even here in hot and humid Mississippi, I can pull my soaps out after 10-12 hours (overnight usually) and let them thaw on the counter and they don't heat back up.
 
I've had that happen a lot, actually. It has happened after I've cut it (I'm dreadfully impatient so rarely leave a soap inthe mold for longer than a day, even ungelled) and it's almost always right around the 24 hour mark. Never happens with gelled soap of course but the ungelled ones will try to go through gel stage. Because they are cut, the bars don't get hot enough to turn into blobby gel (thankfully) and I have never gotten the partial gel ring with this because the heat is dispersed. It can actually pop your colors out a bit, which is nice. I don't worry about it because it has never caused a mess but I have assumed that either the exposure to air has triggered saponification to speed up or the timing is a factor in the saponification cycle because I could practically set a clock by it. It lasts for maybe an hour, max.

This has happened with soap I have not refrigerated or frozen, so it seems for me to be any ungelled soap.
 
How long were you leaving them in the freezer? Even here in hot and humid Mississippi, I can pull my soaps out after 10-12 hours (overnight usually) and let them thaw on the counter and they don't heat back up.
Overnight and the naughty fo still overheats after it is thawed. I am not talking about just gelling, this is gelling and going liquid after thawing. I finally got past it by leaving it 72 hrs in the freezer which is the magic number for saponification and it did not happen. But then problem #2 the scent fades terribly
 
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I out them in the freezer for 3-4 hours, then move it to the fridge over night. Wait all day for them to cone to room temp, then cut.
 
Yes, I have had partial gel after taking milk soap out of the freezer. I now leave it in the freezer for a couple of days or more.
 
Can you tell me more about this 40% lye? I have my recipe at 7%SF, will the 40% lye effect this? I used the Brambleberry lye calculator to figure out my recipe. I haven't done much research for the lye and water discounts.
 
The concentration of the lye water doesn't affect your SF in any way because the amount of lye needed is set; the only thing changing is the amount of water. When you use a strong lye solution (smaller amount of water for the same amount of lye) that is 40%, you can have much longer to work with your soap at emulsion and light trace as long as you don't overSB (you stop SB'ing at emulsion) and you use an FO or EO that has no acceleration, and I mean no acceleration. It seems counter intuitive that you would have a longer working period, but it's true.
 
^^^ While I agree with Newbie for the most part, but a fast moving recipe can still trace faster with a high lye concentration. I find a 34% lye concentration easy to work with and does not heat up like a lower lye concentration of 25-27%, which is soap calcs default of 38% water as percent of oil weight
 
So I learned that my soap recipe was at 28% lye concentration, so I tried the same recipe done at 32% lye concentration. Ive also learned that my recipe has a high iodine value which makes it softer. Ive always tried to avoid gel phase, usually make soap around 83 degrees Fahrenheit, this recipe wants to gel no matter what I do (put in freezer) but after it comes out and comes to room temp it gels anyway. Been so frustrating getting partial gels, to ive decided to embrace it and encourage gel and today the new batch at 32% lye concentration, didn't start to gel until like 15 hours later, I thought gel phase occurs within the first few hrs.
 
So I learned that my soap recipe was at 28% lye concentration, so I tried the same recipe done at 32% lye concentration. Ive also learned that my recipe has a high iodine value which makes it softer. Ive always tried to avoid gel phase, usually make soap around 83 degrees Fahrenheit, this recipe wants to gel no matter what I do (put in freezer) but after it comes out and comes to room temp it gels anyway. Been so frustrating getting partial gels, to ive decided to embrace it and encourage gel and today the new batch at 32% lye concentration, didn't start to gel until like 15 hours later, I thought gel phase occurs within the first few hrs.

If you are looking to ensure full gel, you should use a higher water amount. Maybe 28-30% lye concentration.

If you would rather avoid gel, use a higher lye concentration, 35-40%. If your recipe is very eager to gel, go with 40% if you want to prevent it.

As you discovered, fridge and freezer are not only an inconvenient way to soap but often ineffective.
 
If you are looking to ensure full gel, you should use a higher water amount. Maybe 28-30% lye concentration.

If you would rather avoid gel, use a higher lye concentration, 35-40%. If your recipe is very eager to gel, go with 40% if you want to prevent it.

As you discovered, fridge and freezer are not only an inconvenient way to soap but often ineffective.


Thank you so much for your input! :)
 

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