How hot is too hot?

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Shaylyn Valdez

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Hello! I just had a simple-ish question... How much should I cool down my lye before soaping? I sometimes get impatient and poor not long after I create my lye solution, and I want to know if I should wait till a certain temperature for my lye to be at before I mix with my oils. I want to force gel phase but am worried that if I soap too hot my soap will crack or I will get a soap volcano. How much do temps matter? What should my lye be? How do I ensure my soap does not crack but I still get gel phase?
 
Personally, I cool to 100. I wrap my batch in a blanket and always get gel without overheating. If it's really cool, I may put a heating pad underneath the blanket. The exception would be if I'm doing a milk soap. Those I only cover and don't wrap.
 
Type into the search engine - temperature of lye and oils, lots of previous threads come up, this is asked all the time. There is one from only 2 weeks ago.
 
Type into the search engine - temperature of lye and oils, lots of previous threads come up, this is asked all the time. There is one from only 2 weeks ago.
I’ve actually been searching the forums... none answered if it would affect my soap overheating which is why I asked....
 
I like my mixture to have a temp of 110 Fahrenheit or below...that being said, I have to have my oils above 90, so I don't have that much to work with in terms of temp for the lye water. Probably the hottest I've added it is 120F.
 
Hello! I just had a simple-ish question... How much should I cool down my lye before soaping? I sometimes get impatient and poor not long after I create my lye solution, and I want to know if I should wait till a certain temperature for my lye to be at before I mix with my oils. I want to force gel phase but am worried that if I soap too hot my soap will crack or I will get a soap volcano. How much do temps matter? What should my lye be? How do I ensure my soap does not crack but I still get gel phase?
The reason you're not getting a "simple" answer is because the exact temperature for your lye to just barely prevent overheating depends on your oils and their temperature, how much liquid you're using, what your liquids are, what your additives are, batch size, mold size, ambient temperature, and the behavior of your EO or FO. All of these things affect if, how fast, and how much your batter will heat up, and by extension, how cool you want your mixture, including your lye, to start with.
ETA: how much your batter is insulated also plays a factor in whether or not it will overheat.
 
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Depending on your soap formula, hot & even warm lye solution can cause the soap to overhet very quickly. Some soaps will crack as they set up in the mold when they overheat, but not all do; again, it depends on the formula & your environmental conditions as well, but more on the formula.

A soap recipe high in CO cracks easily. I have stopped the top from cracking from advancing by simply lifting the old up off the surface upon which it sat and placting it on a slotted rack which provides more air flow beneath the mold, and help cool it down faster. In that instance it was a hot day in Texas and the recipe was about 30% CO (not my recipe; I won't use soap with that much CO). When making 100% CO soap for laundry soap, even that doesn't stop it from cracking, but it doesn't matter because it's not for bathing anyway.

So the simple answer, is, Yes, temperatures do matter. But so does the formula. I prefer to soap with oils that are clear and not cloudy (the hard oils that are melted to liquid), which is usually fairly warm depending on which oils I use in a particular recipe, and the lye solution at room temperature or a bit warmer if my house is cold (like it is in the winter).

With a high liquid oil containing recipe, I can soap much cooler so in that case, I tend to do everything at room temperature.

And it's not only temperatures that can cause soap to heat up, but some fragrances and some additives & additional ingredients can as well. So that's why we say' it depends....'
 
Hello! I just had a simple-ish question... How much should I cool down my lye before soaping? I sometimes get impatient and poor not long after I create my lye solution, and I want to know if I should wait till a certain temperature for my lye to be at before I mix with my oils. I want to force gel phase but am worried that if I soap too hot my soap will crack or I will get a soap volcano. How much do temps matter? What should my lye be? How do I ensure my soap does not crack but I still get gel phase?

And as noted by others there can be a lot of contributing factors to having soap that cracks or volcanos beyond the temperature of your lye solution and/or oils and butters. As an example I make Goat Milk Soap with fresh goat milk; regardless that my lye solution is around 70F and my oils/butters are around 80F, I have to refrigerate my GMS if it is above 75F in my house. Believe me when I say that you do NOT want your GMS to overheat...you end up with gross smelling and looking, and oily soap. As another example I've used the 'heat transfer method'; it's where you take your freshly made lye solution that's about 220F and pour it directly in your container to melt your hard oils and butters.
 

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