What happens if lye water is below room temp and oils are ~120F?

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ahauer88

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Will any adverse effects happen? Just curious. All of the advice I've seen is to have the lye water and oils as close as possible in temperature.

Here's what's going on, I went home for my lunch break and mixed up lye and water and measured my oils for this goat's milk soap I want to try making later, just so I can cut down on the amount of time involved in the project when I'm home for the evening.

I put the lye water out in the garage and my oils are ready to go in the kitchen. But now I'm thinking duh, now my lye water is going to be cold and my oils warm when I'm ready to mix! Since it is a GM soap I am going to stick it in the fridge or freezer afterwards anyway to prevent partial gel but I guess I never really knew if a big temp difference between the lye water/oils when combined would have any "bad" effects.

Thanks a lot for helping out this newbie.
 
The temp difference between the lye solution and the fats isn't particularly important. What does affect the outcome of your soap making is the initial temp of the batter right after you mix the lye solution and the fats.

If a person follows the suggestion to have the temps of the lye and fat be similar, then they can safely say the batter temp is going to be pretty close to that temp too. That can be a good way to get a beginning soaper started on the right foot, but it's not strictly necessary after a person gets more experience. Equalizing these temps is time consuming and not really necessary.

On the other hand, if the lye and fat temps are far apart, it can be harder to estimate the initial batter temp. A person can't assume the temp will be exactly in the middle between the fat and lye temps, because there is typically a lot more fat in a batch of soap than lye solution.

The initial batter temp in my experience tends to be somewhat closer to the fat temp than the lye temp for a basic soap recipe. There can also be some unexpected warming effects that can occur when the lye reacts with additives such as sugars and additional water. These things can also affect the starting batter temp -- usually the temp is somewhat higher than expected.

The way to learn what will happen is to take the temps of your lye solution and fats, and then the temp of the starting batter. Even just feeling the side of the containers -- cool to the hand, neutral temp, lukewarm, toasty warm? -- is good enough if you don't care to use a thermometer. This information will help you learn how to predict what the batter temp will be.
 
When I soap in summer, I mix my lye with 100% ice instead of water and put it in the fridge to cool down even more so it's almost always below room temperature.
When soaping with room temp or just slightly warmer oil i found it may got some stearic spots when using lots of hard oil.
When soaping with very warm oil I don't see anything out of usual, no issue related to temperature whatsoever.
 
Will any adverse effects happen? Just curious. All of the advice I've seen is to have the lye water and oils as close as possible in temperature.

I was told in a soap class I took a half dozen years ago that lye and oils HAD to be at 110F. I’ve since learned that it’s not true.

When I started making soap earlier this year, hubby had a bit of a reaction to the smell of lye so the next time I mixed it in the garage and waited for it too cool. It was such a PITA having to wait FOR-EV-ER for the lye to cool, so I started mixing up a bunch of containers the night before and letting it cool in the garage. That got old fast because sometimes something would come up and now I’ve lye sitting in the garage.

Then I saw someone on YouTube use frozen distilled water. No fumes, no nasty lye smell and no waiting.

I soap at all sorts of temps depending on what I’ve got going on.
 
I was told in a soap class I took a half dozen years ago that lye and oils HAD to be at 110F. I’ve since learned that it’s not true.

When I started making soap earlier this year, hubby had a bit of a reaction to the smell of lye so the next time I mixed it in the garage and waited for it too cool. It was such a PITA having to wait FOR-EV-ER for the lye to cool, so I started mixing up a bunch of containers the night before and letting it cool in the garage. That got old fast because sometimes something would come up and now I’ve lye sitting in the garage.

Then I saw someone on YouTube use frozen distilled water. No fumes, no nasty lye smell and no waiting.

I soap at all sorts of temps depending on what I’ve got going on.
I mix my lye and oils at 110*. This, for me in my soaping environment, ensures gel, avoids stearic spots and weird lumps and bumps and gives me consistent results. Each to their own.
 
I make several batches at one time, but mix the lye for each first. I need to start master batching lye, but don't have the containers for that yet. By the time each oil recipe is ready, my lye solutions are usually at room temp and the oil/butters are warmer (usually 90 - 120 depending on what I'm making, additives, etc).

My experience is similar to what @DeeAnna posted above - the soap batter temp is most important. In general, the warmer my batter is after mixing lye with oils, the faster it will trace. That temp for me has always depended on not only the lye and oil temps, but also any additives that might cause an increase in heat to the batter as the saponification starts.

Since there are so many variables (temps, additives, what your fragrance does to the batter, etc), the best you can do is measure the temps before combining and make lots of notes. This is how I know that I usually don't have any issues with room temp lye and warm oils. Hot oils (120 or greater) tend to be ashier soaps and trace quickly even when I add room temp lye. I know some people have no issue with using these temps, so the humidity in my soap studio probably has an affect as well. "Soap Science" is interesting :)
 
I mix my lye and oils at 110*. This, for me in my soaping environment, ensures gel, avoids stearic spots and weird lumps and bumps and gives me consistent results. Each to their own.

Personal preference. I work full-time outside the home with a 2+ hour daily commute so I only get to soap on the weekends. I also have a husband who is sensitive to certain smells that can trigger headaches and nausea and as he is already disabled, I don't need to add to it. The smell of freshly made lye is one such trigger and using frozen distilled water works for him to the extent that he doesn't even know that I have mixed any lye. And then there are the scents...I absolutely cannot make bath salts in the house even if I open all the doors and windows, something in the Poly80 changes the FO and he is down for the count for at least 12 hours. Last batch I made...in the garage...while he was gone...with the door open...and it was still 24 hours before he could go into the garage. Sometimes it's a guessing game on what scents I can and cannot use while he is home...we're working on a list.
 
Personal preference. I work full-time outside the home with a 2+ hour daily commute so I only get to soap on the weekends. I also have a husband who is sensitive to certain smells that can trigger headaches and nausea and as he is already disabled, I don't need to add to it. The smell of freshly made lye is one such trigger and using frozen distilled water works for him to the extent that he doesn't even know that I have mixed any lye. And then there are the scents...I absolutely cannot make bath salts in the house even if I open all the doors and windows, something in the Poly80 changes the FO and he is down for the count for at least 12 hours. Last batch I made...in the garage...while he was gone...with the door open...and it was still 24 hours before he could go into the garage. Sometimes it's a guessing game on what scents I can and cannot use while he is home...we're working on a list.
I don't use fresh made lye. I masterbatch and pour out the required amount. Then I add the extra water to the lye and it starts to heat up again. It doesn't smell when it does this. I wait for it to cool again - takes about as long as it takes me to organise my oils - and mix together at about 110*F.
 
I don't use fresh made lye. I masterbatch and pour out the required amount. Then I add the extra water to the lye and it starts to heat up again. It doesn't smell when it does this. I wait for it to cool again - takes about as long as it takes me to organise my oils - and mix together at about 110*F.

I haven’t tried master batching yet, no real reason as I’m not making soap everyday or making larger quantities.
 

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