Is it important that oil & lye/water temps be within 10 degrees when blending?

Soapmaking Forum

Help Support Soapmaking Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

akseattle

Well-Known Member
Joined
Apr 10, 2023
Messages
449
Reaction score
736
Location
Seattle, Washington
Okay, gang, I have another newbie question.
Is it important that oil & lye/water temperatures be within 10 degrees of each other when blending?
In a SoapQueen Tutorial, she says:
" For most soapers, the preferred temperature of soaping lye and oils are 120-130 ° F. In addition, many soapers and books believe it is helpful to have the lye and oil within 10 degrees of each other."
She gives an extensive explanation about the pros and cons of the temperature of oils.
Curiously, she doesn't say WHY it's helpful to have lye and oil within 10 degrees of each other. I'm wondering, is this important? and Why?
Who follows this rule and who doesn't?
Thank in advance!
 
No it's not important at all. However, mine tend to naturally be within this range anyway because I mix the lye solution first and set it aside in an ice bath to cool while I melt all my oils and prepare the molds/colours etc.. SO by the time all that is done the oils are usually around 45 degrees celsius (113f) and the lye solution around 38 (100f).
I guess as newbie it might eliminate potential problems by making you think this is necessary, but I'm not sure what they might be.
 
Last edited:
The one reason it can be helpful to have lye and oils somewhat close in temperature is to prevent false trace. This happens when some of the fats congeal because they have cooled too quickly by coming in contact with a cooler lye solution. Because false trace makes the batter look thick, the soaper can mistakenly believe that trace has been reached. The soaper then stops blending, leaving the lye not mixed in well at all, and subject to separating later in the mold, or leaving parts of the soap with excess lye in it.

When false trace happens, you can wait a bit for the batter to heat up. Within a few minutes, it will thin out again so you can see the oily separation.

That being said, I have never experienced false trace, even though my recipes are high in hard fats, such as tallow, lard, and a bit of butters, melted to 160F and cooled to anywhere between 95F and 105F. I combine this mix with master-batched lye solution that is room temperature (70F to 80F based on time of year). So I'm never within 10 degrees, and it doesn't affect my batter at all. YMMV.
 
@KiwiMoose and @AliOop , thank you for your responses. Looks like I don't need to kill myself to honor the 10 degree rule, but, your advice is well taken. As a newbie, I might as well do myself a favor and minimize potential confusion / chaos over false trace!

@AliOop I'm glad you mentioned your oils and butters heat to 160F.
In my first batch, the temperature of oils shot to 170F for a second before I was able to get it off the double boiler.
In my second batch, I sacked the double boiler and just did it directly on my electric stove-- easier to control. But the oils still spiked to 160F. I didn't really know how high is too high.
In M&P, oils are supposed to stay no higher than 165 degrees or properties can start to change, or it smells or other things.
How do you heat your oils?
 
I heat mine on the stove top ( not in a double boiler) and I have no idea what temperature they heat to. I put in the CO, Soy Wax, and Shea in there until they are fully melted (not cloudy) and then turn the heat off. Then I add the liquid oils into that.
 
In M&P, oils are supposed to stay no higher than 165 degrees or properties can start to change, or it smells or other things.
How do you heat your oils?
Well, you can't compare melting M&P melting oils for CP. Recommendations for M&P melting temperatures will be specific to each brand and sub-type of M&P, which is pre-saponified soap with lots of additives - quite different than melting just oils. :)

I mostly use the microwave for melting my oils, but occasionally melt them in stainless pot directly on the stove. With low heat, there is no need for faffing about with a double-boiler. ;)
 
I think the "10 degree rule" can be helpful for the new soap maker. It's easy to see if the fat is at 90F and the lye solution is at 100F, then the soap batter will be around 95F. So it keeps beginners out of trouble and gives them confidence they're doing it "right".

But once a person gets the hang of making soap and what temps they like, this "10 degree rule" can be ignored. The chemistry of saponification doesn't care.

I think the main issues about the initial batter temp are these: If the soap batter is too cold and you're using solid fats like lard, tallow, palm, nut butters, etc. then you risk having to deal with false trace. If it's too hot, then the batter is likely to trace more quickly than you want.

There's a lot of flexibility in how soap makers can measure their temps. You can measure the temp of the ingredients and estimate the initial batter temp from the temp of the ingredients. That's probably a more beginner friendly method. Or you can measure the initial temp of the batter itself, which is more what I do. You can measure the temp with a thermometer if you prefer that or, with more experience, you can estimate the temp using the palm of your hand on the side of the soap pot.
 
Lots of temps and ranges can be used. However, there are a lot of variables that can change the way your soap batter traces and thickens (temps, fragrance, water amount, recipe). I think keeping the temps within 10 degrees and keeping the temps close to the same for each batch helps with consistency and that can allow you to build confidence faster when you are a new soap maker.

I heat oils in a stockpot over the stove. No issues. Think of a restaurant that fries food and it smells bad. Too hot and used the same oils too long. That is what you want to avoid. Also, you don't want to have an accident with hot oils in your kitchen. So, I try to pay attention to the melting and turn off the heat when most of the hard oils are small pieces. Stirring will distribute the heat and the rest will melt.
 
My process is the same as @KiwiMoose . When I was a noob, I was obsessed with temperatures. Now I feel the melted oil pot and the lye solution container. When both are 'warm to the touch', I mix 'em. However, in the winter, in my cool basement soap shop, I do stick a thermometer in the oils and tend to soap at 110-120 just because I'm skirred of stearic spots.
 
Okay, gang, I have another newbie question.
Is it important that oil & lye/water temperatures be within 10 degrees of each other when blending?
In a SoapQueen Tutorial, she says:
" For most soapers, the preferred temperature of soaping lye and oils are 120-130 ° F. In addition, many soapers and books believe it is helpful to have the lye and oil within 10 degrees of each other."
She gives an extensive explanation about the pros and cons of the temperature of oils.
Curiously, she doesn't say WHY it's helpful to have lye and oil within 10 degrees of each other. I'm wondering, is this important? and Why?
Who follows this rule and who doesn't?
Thank in advance!
Frankly I think a lot of the advice from “SoapQueen” is just wrong. She mixes her lye solution in a glass bowl which really bothers me. Even if you disregard the fact that lye etches glass, those large glass bowls are heavy and slippery. Temperatures of 120-130 are really hot. The hotter you soap, the faster it moves. She just has bad advice .
 
I think it's interesting to think about how soapmaking has evolved. The craft has come so far, and we've learned so much from each other! I found a copy of Soap by Ann Bramson, one of the pre-internet pioneer makers, and she states definitively "You are ready to make soap when the lye solution and fats are between 95 and 98 degrees. No lower than 95, no higher than 98." Does anyone still recommend that temp range?

Those tutorials on the old SoapQueen site are aimed at novice makers, and I found them very useful when I started. But even then, most of the instructions say that oil and lye solution temps should be ideally within 10 degrees of each other. I didn't make a note at the time so can't provide the source, but I do recall a video from a few years ago of Anne Marie mentioning that she's no longer as fussy about temperatures as she was when a beginning soapmaker (which for her must have been more than 25 years ago).
 
Measured temps once, never again, too fiddly and time consuming. I sometimes make my lye the day before, then melt the solid oils until just melted and then add lye. No measuring temps, no trouble and less stressful.
This is what I do. But I masterbatch the lye and EDTA sometimes a week before, then get my lard heated enough to melt completely, add my liquid oils, then the lye and EDTA. No fret, no sweat.
 
What temperatures? 😂

Yep. I melt / mix everything the night before & make my soap the next day when everything has cooled off at room temperature. But the actual temperature of everything when I make the soap? No idea :smallshrug: I do occasionally take a temperature reading while everything is heating up, but after that, I don't really care. My oils / butters get up around 185º or so during the melting phase. That's enough to melt everything really well & for my oils & butters to 'come together', so to speak.

To avoid stearic spots, which @Zing mentioned, I also heat everything together, liquid oils & solid butters, and allow them to cool overnight all together after giving them a good whiz with my stick blender. I have not yet experienced stearic spots, so it seems my method of preparing things helps me avoid them.

I don't bother with a double boiler unless I am making salves, lip balms, body butters & related. For soap making oils & butters, I heat directly on my gas stove in a large stainless steel pot. I don't do microwaves, ever, for any reason.
 
Well....I'm fixin to get my booty in here and try it. The time thing has really slowed me down as far as trying to find a rhythm or system. Slimlining the time it takes to make soap. Questions: Using ice in lye- do you measure the water and then make ice cubes out of it? Or measure the ice cubes weight??
 
Well....I'm fixin to get my booty in here and try it. The time thing has really slowed me down as far as trying to find a rhythm or system. Slimlining the time it takes to make soap. Questions: Using ice in lye- do you measure the water and then make ice cubes out of it? Or measure the ice cubes weight??
Doesn’t matter, ice and water are the same weight. Whichever way works for you. I use my master batched lye solution, melt my hard fats, and add my liquid oils to the melted hard fats which cools it down. I don’t really take temperatures anymore. Just feel the outside of the container.
 
Well....I'm fixin to get my booty in here and try it. The time thing has really slowed me down as far as trying to find a rhythm or system. Slimlining the time it takes to make soap. Questions: Using ice in lye- do you measure the water and then make ice cubes out of it? Or measure the ice cubes weight??
I measure the water, then make ice. Then measure the ice.
 
Well....I'm fixin to get my booty in here and try it. The time thing has really slowed me down as far as trying to find a rhythm or system. Slimlining the time it takes to make soap. Questions: Using ice in lye- do you measure the water and then make ice cubes out of it? Or measure the ice cubes weight??
I freeze my distilled water and aloe juice in ice cube trays, then store them in buckets in my freezer. When making soap, I weigh the ice and add more water to get the correct amount of liquid for my recipe. I always add sodium citrate, so I make sure that there is enough water to properly dissolve that, as well as any other additives that need some of the batch water to dissolve when they are included in the soap I am making. Doing this, I rarely have to wait for my lye solution to cool.
 
Back
Top