CP: Does temperature matter? (lye/oils)

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Unless things have changed IR thermonenters are for surface temp, and the middle of your batter can be much different so I would use a probe type. I am like JCandleattic that does not check temp, but like DeeAnna if it is comfortable to my hand it is fine, I even soap tallow, palm and lard recipes when they are a little cloudy, but I force gel by putting my molds in a long shallow crate with a heat blanket on top and heating pad on the bottom. My molds will not fit in my oven so I had to come up with a different way. I just do not have the time to fiddle and worry about temps, I also work with master batch 50/50 lye solutions unless I am making a full vinegar soap
 
That I am aware of , but still prefer a probe if I want actual temperature especially if working with lotions
Yep, agreed, with lotions I absolutely take temps, and I also prefer a probe thermometer, - I've never liked the IR thermometers, but with my soapmaking - nope, I find there is no need, and it's just an added unnecessary step for me.
 
If you ever are concerned about your oven temperature not reading correctly when you CPOP (I do because I have experienced oven malfunctions in the past, so I remain diligent about that), then you can always buy an oven thermometer that hangs from the rack for a much more reasonable price (around $3.00 more or less, depending on where you go.)

I know what CPOP is but what is the purpose of it? Oops, sorry - just read Irish Lass above & it was explained.
 
Since I soap room temp with my oils barely and sometimes hazy I put my molds in long plastic totes with lids on a heating pad with an electric blanket wrapped around them. If I layer 3 totes I put a lap heat blanket between the totes, then cover with the electric blanket. My soaps are always very hard to force them to gel. This does no apply to naughty heater type fo's such as some florals. If something goes south and the soap separates (does not happen often) the tote will catch any leakage. I will caution to keep an eye on progress and do not let it overheat or leave blankets on if leaving the house. One time I had a mess in my oven from an overheated soap and that ended the oven method for me, plus the fact my molds do not fit in the oven well and I always make multiple batches.
 
Temperature control is important in soap making. Get the little IR thermometer from Harborfreight Tools. $11.99 -- cheap!
I always prefer to control all variables. Even in a highly controlled setting, CP soap sometimes has a personality of its own. Being a bit more careful and scientific about the process doesn't make it less artistic.
 
I have seen on Youtube that people put hot lye in cold oils, to save time and make it easy since the hot lye will melt the hard oils. And it looks like they are getting nice soaps in the end. So I doubt that oil and lye have to be within 10 degrees of eachother to make great soaps. But I have not tried, so I have no idea.

But I do know that a little too hot oils mixed with sizzling hot lye when doing countertop hot process, will end with a massive volcano and vaseline stage almost in an instant. Especially with a lye concentration of around 45%. And it will harden up almost in front of your very eyes. So that can be a challenge :-D So I will watch my temperatures a little bit more the next time I do hot process, to reduce the stress factor.
 
I have seen on Youtube that people put hot lye in cold oils, to save time and make it easy since the hot lye will melt the hard oils.
This is an advanced technique used by many CP soapers I know. Once the hard oils are melted by the hot lye solution, the liquid oil(s) is warmed before adding to the batch and SB-ing to trace. I tried it once. Works quite nicely and it does speed up the process -- you don't have to wait for the lye solution to cool down before combining with the fats.
 
And this "thermal transfer" method works best for recipes that don't have a high % of lard, tallow, palm, or butters. If there are enough of these solid fats, there's not enough thermal energy in the lye solution to fully melt the fat.
 
And this "thermal transfer" method works best for recipes that don't have a high % of lard, tallow, palm, or butters.
Hmmm. This is the recipe I used, in case anyone wants to try it:
Alan's Tallow.png
 
And this "thermal transfer" method works best for recipes that don't have a high % of lard, tallow, palm, or butters. If there are enough of these solid fats, there's not enough thermal energy in the lye solution to fully melt the fat.
I was wondering about that myself, Thanks
 
I have done Lye almost 20 degrees hotter then the oils, but under 130, and all it good. But the oils were melted.
The oils just cool off faster then the Lye does.
I don't have Ice cubes, we use the "re-usable" ones. Small freezer :(

edit to fix wrong word
 
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As I always say on this topic, the idea of the oils and lye being a similar temperature gives beginners something to aim for. If no information on that front is given, what would you do? Let it cool down or use it hot and fresh? As we know, that can cause issues. The advice is good advice to make a successful batch, but is not a rule for general soaping.
 
I keep my oils in the basement. For me, thermal transfer works okay in the summer - when the basement is between 70-80. But it doesn't work in the winter, when the basement is colder. But I also use a lot of lard.
 
I have several IRL soaper friends, and between the 4 of us we all use different methods.

Friend 1 (who taught me how to make soap) Melts her oils together, mixes her lye, covers everything and mixes it all together the next day. I believe this is "true" room temp method. *note, she also does not have children or other people living with her, or naughty cats that get on the counter. Her recipe is +60% liquid oils. When she taught me, she had me bring each temp to 110°F approximately.

Friend 2 soaps at 95°F.

Friend 3 uses heat transfer with fresh lye to melt her coconut oil and adds in her room temp liquid oils. She doesn't use tallow or butters.

I use 'kind of' heat transfer method. I masterbatch all of my oils into big buckets - I use tallow, cocoa butter, shea butter and coconut for hard oils at 65% of my recipe. If my soap lab is really warm, I have to do a lot of mixing as there will be some liquid in the bucket. I do not use my MB oils if it doesn't incorporate back in, or if there are visible solid chunks. I measure out my MB, which is very creamy consistency, and add fresh lye.

I have tried the "true" heat transfer method with other recipes, some of the trick is adding in solid oils one at a time in order of highest melting point first, and using smaller chunks. (For butters I have only tried this with shea, I have not tried it with cocoa butter, or other hard butters.) I think the recipe I used it for was 1:1 hard to liquid, with lard, coconut, and shea for hard oils, and olive and castor for the liquid. These were small batches at 1lb oils, so for larger batches I could imagine the results would vary if I were to try it again at larger amounts.

It is interesting that everyone has different methods, and different results based on recipes, but yet we all end up with soap. I agree with TEG that bringing everything to similar temps is a great way to start out and brings reliable results. It certainly teaches one lessons when one tries other methods.

(For a good laugh, before I found this forum, I thought I invented the heat transfer method because I couldn't find it anywhere in my reading. It occured to me at my third batch that the lye is hot and would melt my oils - at that time I was doing 30/30/30/10 lard, coconut, olive and castor - and I tried it and it turned into soap! I thought I was a genius! A year later I joined here and discovered that it is more common than not...)
 
The only time that heat transfer was a big issue for me was with cocoa butter. It was in "disc" form, about 2cm diameter. They did not want to melt at all.

Usually, if I measure out my oils and then look at making my lye solution, the oils have softened enough to be okay. I normally have 50% lard and around 20% co, neither of which are particularly hard to melt, though, especially if they have been sat waiting in the pot while I mix my solution.
 
Since I use a fair bit of Palm I heat the oils, don't want Stearic spots which I got when I didn't heat oils high enough. So I am not comfortable with heat transferr.
 

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