What is room temperature?

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As a newbie, I could use some help with “room temperature” from the experienced makers! Room temperature in Fahrenheit for my house is typically in the high 60s or, if I’m feeling chilly I may push the thermostat into the low 70s when the heat is on. Temps are typically in the high 70s or low 80s during the summer. During these early months of my soapmaking journey (with the house in the cooler temperature range) I’ve been starting at about 105 but I’m finding that my batter can cool down a lot if I’m using a recipe that is slow to trace and I’m experimenting with swirls and pours. The batter is cooling to 80 or possibly even a little bit lower. This will become less of a problem as the weather outside gets warmer and the room temperature in my house goes up.

I’m pretty clear from what I’ve been reading here on SMF that I should avoid high temps and especially adding cool lye to oils that are close to the boiling point of water. Soaping cooler will also help to slow trace. But I should stay warm enough to keep my hard oils/butters liquid... that’s where I am getting a bit hung up, because it seems to me that some are soaping at room temperature with recipes that have hard oils and butters. So, back to the question - what is room temperature? :)
 
I think how cool you can soap really depends on your recipe. I tend to use a lot of hard oils/butters, and cool them just so they don't yet solidify. I don't measure the temp usually, but it is in the "just warm to the touch" range (I would say around 90--100F). I guess that's not really room temperature, but f I go much cooler than that, my oils start getting cloudy (but I use beeswax and that requires higher temp than usual).
If your recipe has mostly liquid oils, or fats with lower melt temperature, then you can really soap at room temp.
Just experiment and see what works! Melt them, mix them, and see when they start solidifying again.
 
I generally think room temp is a catch phrase for using lye water that has completely cooled, and oils only just warmed to the point of being melted clear, no warmer.

For most of my soaps, room temp means that when I touch the outside of my bowl of oils, they don't feel warm or only just slightly warm. So blood temperature I guess. Since I soap with goats milk my lye mixture if I've been patient is usually cold when touching the outside of the bowl.

I should also mention I don't have a thermometer so unsure what actual temps I use
 
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The temperature that I can soap at and be able to use colors and different scents depends on the oils that are in the recipe.
If I am using a recipe with a high percentage of lard, soy wax or coconut ( some are and) then I will need to soap cool and move fast. Water content also makes a big difference ( I use water to lye (alkali) ratio).

If I am using a high percentage of lard and wax "room temperature" could be as high as 135 degrees F. If I have a slow moving recipe I can wait and soap cool as long as the oils will stay liquid (palm olive).

Just from memory so I may have some of this wonky.
Steve
 
IMO, room temperature is ... room temperature. Whatever the ambient air temperature is at the time you make soap.

If I warm something above the air temperature in the space in which I'm soaping -- even a little bit -- the warmed ingredient is not at "room temperature" anymore. I might call it slightly warmed ... lukewarm ... mildly warm to the touch. I might say it's 100 F or whatever. But I do not call it room temperature.

In the winter time I might make slight adjustments to my method to keep the soap from cooling down too much in the mold to avoid partial gel -- maybe a kitchen towel over the top of the mold to hold it a bit more warmth. In summer, I try to make sure the soap doesn't get overly warm -- maybe just cover the top with a sheet of waxed paper to keep the dust off.
 
To me 'room temperature' is the temperature of my room. Like you, Mobjack, my house is on the cooler side in the cool months and on the warmer side in the warmer months.

Of course not everyone likes their house temperatures as cool as we do in the cool months. I know people who keep their houses much warmer in the winter than I can tolerate. So it's a relative thing, when a soapmaker (or anybody else) talks about 'room temperature'.

What I have noticed is that some recipes don't do well at my cooler room temperatures in the cool months, so I soap warmer. It's still technically CP soap, but I have to start out warmer and maintain a warmer temperature to prevent false trace with harder oils.

Anyway, to avoid false trace, I try to maintain an oil temp that keeps the combined melted oils clear (not cloudy). And because I masterbatch my lye solution at 50%, it sometimes creates a problem with the lye being too cool. So when there are a lot of hard oils in my soap mixture, I heat the additional water before adding it the 50% lye solution. Not a lot of heat, just about 15-20 degrees F below my desired lye temperature. Then when I add the water, the solution heats up enough to be close to the temperature of the oils while they are still clear. This keeps the batter warmer and seems to work for me.

I tend to make smaller batches, so they can cool down pretty fast in a cool environment.
 
@earlene thanks for the tips. Given where I am on the learning curve, I’m still working with very small batches of a pound or less. They cool super fast when the room temp is in the high 60s! It’s definitely something to keep in mind for newbies who are sticking to small batches in the beginning. Even though I started warmer on a batch this morning, some of my batter got down to 77 df and I had to warm it up in a water bath.
 
I've never taken temps, and I've always gone with the 'warm to the touch' approach ( that's both my oils and my lye solution). I use soy wax, shea butter, and coconut oil in every recipe and with soy wax at 20% I have to be careful it doesn't get too cool. My standard recipe is about 48% hard oils/52% soft oils. I estimate that I soap at 95 - 100f.
I had awful problems with soap over heating this past summer - we had some very hot and humid days. However, I'm interested to see what will happen next summer - we have installed a whole house central heating/cooling system which allows us to maintain a uniform temperature which will be around 20 degrees I guess (circa 70f). We are coming into winter soon and I don't think we will get too cold in here for the same reason.
 
I've never taken temps, and I've always gone with the 'warm to the touch' approach ( that's both my oils and my lye solution). I use soy wax, shea butter, and coconut oil in every recipe and with soy wax at 20% I have to be careful it doesn't get too cool. My standard recipe is about 48% hard oils/52% soft oils. I estimate that I soap at 95 - 100f.

Thanks @KiwiMoose :). Based on the feedback, the mixtures with waxes and butters need to be “warm” but they don’t need to be above the melting point temp for the ingredient that has the highest melting point. That’s what I was thinking at first. Even though the melting point of soy wax is around 120-140 F, you have success in a cooler temp range. My recipes vary a bit, but most have hard oil proportions close to yours. My biggest challenge so far has been keeping my mini-batches warm enough while I’m layering, swirling, etc. Even if I start at 110 F, the batter can fall to below 80 F before I’m done. Summer is coming here so I expect to have less of a problem as my house warms up.
 
Your geek word for the day is hysteresis (hiss-tur-EE-sis).

The melting point of a non-uniform material like fat is not necessarily the same as its solidifying point -- the point at which the liquid fat starts to turn solid again. Typically, fat will have to cool somewhat below its melting temp before it starts to solidify again. This behavior is an example of hysteresis.
 
Your geek word for the day is hysteresis (hiss-tur-EE-sis).

The melting point of a non-uniform material like fat is not necessarily the same as its solidifying point -- the point at which the liquid fat starts to turn solid again. Typically, fat will have to cool somewhat below its melting temp before it starts to solidify again. This behavior is an example of hysteresis.

Perfect! One of my best friends was a chemical engineer, but she died almost 10 yrs ago. She would have gotten a kick out of my sudden deep interest is chemistry! I really appreciate it when you share your deeper knowledge of what’s going on. The article you wrote (on your website) about the changes in soap over time is a great example. We use the term hysteresis in ecology, too, when we’re talking about how ecological systems don’t necessarily recover to the same state they were in before a disturbance once the disturbance is gone.
 
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When I soap at room temp I have had trouble getting my soap to go thru gel stage, even with “blanketing” , tho I have not tried an oven or heat pad...since I use micas for colorants, I want the gel phase to “ bring out the Bright”.
 
"...We use the term hysteresis in ecology, too, when we’re talking about how ecological systems don’t necessarily recover to the same state they were in before a disturbance once the disturbance is gone...."

Yep, the word is useful in a lot of disciplines. It's a word I seldom get to use so I just had to trot it out here since it applied so nicely to the discussion. It's one of those words that have a seriously cool meaning, but is utterly inappropriate and weird in normal conversation. Other favorites of mine are nucleation and thixotropic, but neither apply to your thread here, so I'll save 'em for another time. :rolleyes:

I'm a chemical engineer too. I'm sad to hear your friend passed.
 
I don't really understand the pros of "room temperature." What's the difference what you call it? I guess just to be clear for communication. I use the heat transfer method. It never fails me, summer or winter but that would depend on where you keep your harder fats.

Sorry, not trying to steer O.T.
 
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I don't really understand the pros of "room temperature." What's the difference what you call it? I guess just to be clear for communication. I use the heat transfer method. It never fails me, summer or winter but that would depend on where you keep your harder fats.

My interpretation of the discussion is less about the pros and cons of the so-called "room temperature method" or the "heat transfer method" and more about the fact that cold process soap making can be fairly sensitive to the ambient temperature if you pay close attention to the details.

If your ambient room temperature in winter is maybe 60 F / 20 C, you might want to use slightly different techniques to ensure a good outcome than when you make soap in summer when the ambient temp is more like 90 F / 68 C or hotter. This sensitivity to ambient temperature increases when making small batches, as Mobjack is doing, because the size of the batch also affects the ability of the soap to remain warm enough while saponifying.
 
I don't really understand the pros of "room temperature." What's the difference what you call it? I guess just to be clear for communication. I use the heat transfer method. It never fails me, summer or winter but that would depend on where you keep your harder fats.

For me, I do room temp because I use 100% frozen goat milk in place of water. So I can't heat transfer. I also have ingredients that are prone to heating up, especially when I then add honey. So I soap as cool as possible to avoid my soap overheating. I also prevent gel phase where possible to keep the soap lighter otherwise it affects my colours, soaping at room temp usually lets me do that without having to put the soap in a fridge or freezer like most GM soapers do (my moulds don't fit lol)

In a more general sense, room temp soaping can also slow down trace and give you more working time
 
For me, I do room temp because I use 100% frozen goat milk in place of water. So I can't heat transfer. I also have ingredients that are prone to heating up, especially when I then add honey. So I soap as cool as possible to avoid my soap overheating. I also prevent gel phase where possible to keep the soap lighter otherwise it affects my colours, soaping at room temp usually lets me do that without having to put the soap in a fridge or freezer like most GM soapers do (my moulds don't fit lol)

In a more general sense, room temp soaping can also slow down trace and give you more working time
Got it. I don't like gelling either. My moulds are also too big to fit in the fridge.
 
I did not ask my question in the most direct way, but it was mostly focused on just how low the batter temperature can go without risking a firming up of the hard butters and oils that leads to false trace. Is it 80 F, 75 F, 70 F, etc.? What I’ve learned is that makers who work at room temperatures that are on the cool side may start with the batter a little warmer when the recipe has a higher fraction of hard oils and butters. That allows them to compensate for cool rooms temps, masterbatched lye and avoid false trace. Earlene also compensates by using warmer water to make up the difference when she uses masterbatched lye.

I can say from experience that the working time and the batch size also make a difference. Soap cools down while you’re pouring, swirling, layering, etc, especially if you’re slow like I am. Let’s say for a starting point that the critical temperature for avoiding false trace is 80 F, your batter starting temperature is 85 F, the batch is small and the room temperature is 65 F. The batter could easily cool down to below 80 F in the time it takes a newbie to build layers or make swirls. I’ve had small batches of batter (1 lb of oils) cool down from over 100 F to less than 80 F twice now while I’ve been trying to build layers and let them set up a little. The problem is exacerbated when the batter is split up for different colors or additives. Yesterday I had to stop what I was doing and heat my batter in a water bath because it was down to 77 degrees. I’m sure this cooling will become less of a problem as my technique gets better/speeds up. Newbies like me should probably stick with easier designs early on while learning about how recipes, trace, temperature and batch size influence batter behavior. That’s a lot of variables to take into consideration without even bringing up the effects of FOs, clays, other additives and the mighty stick blender. After trying something pretty complicated yesterday, which went okay but not exactly the way I hoped it would, I followed up by making a much easier soap. It was still fun and I know it will get easier to make the complicated designs when I gain more experience.
 
I did not ask my question in the most direct way, but it was mostly focused on just how low the batter temperature can go without risking a firming up of the hard butters and oils that leads to false trace. Is it 80 F, 75 F, 70 F, etc.? What I’ve learned is that makers who work at room temperatures that are on the cool side may start with the batter a little warmer when the recipe has a higher fraction of hard oils and butters. That allows them to compensate for cool rooms temps, masterbatched lye and avoid false trace. Earlene also compensates by using warmer water to make up the difference when she uses masterbatched lye.

I can say from experience that the working time and the batch size also make a difference. Soap cools down while you’re pouring, swirling, layering, etc, especially if you’re slow like I am. Let’s say for a starting point that the critical temperature for avoiding false trace is 80 F, your batter starting temperature is 85 F, the batch is small and the room temperature is 65 F. The batter could easily cool down to below 80 F in the time it takes a newbie to build layers or make swirls. I’ve had small batches of batter (1 lb of oils) cool down from over 100 F to less than 80 F twice now while I’ve been trying to build layers and let them set up a little. The problem is exacerbated when the batter is split up for different colors or additives. Yesterday I had to stop what I was doing and heat my batter in a water bath because it was down to 77 degrees. I’m sure this cooling will become less of a problem as my technique gets better/speeds up. Newbies like me should probably stick with easier designs early on while learning about how recipes, trace, temperature and batch size influence batter behavior. That’s a lot of variables to take into consideration without even bringing up the effects of FOs, clays, other additives and the mighty stick blender. After trying something pretty complicated yesterday, which went okay but not exactly the way I hoped it would, I followed up by making a much easier soap. It was still fun and I know it will get easier to make the complicated designs when I gain more experience.
Yes, I see what you mean. I can't really answer to that. When I started soapmaking many years ago, I learned only one method. Cold process, having melted your hard fats, adding your liquid oils, cooling to 95 degrees, having lye water mixed ahead of time so that it also could be cooled to 95 degrees before adding that to the oils. Stirring without knowing anything about a stick blender! Yes, stirring for 50 minutes to reach a medium trace. It was a good slow method that gave me plenty of time to watch the batter and think.
 
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