Lye Mix and Oils Temperature- Does it really matter?

[SaltedFig]

I do a heat check, if I've had to warm my oils, by holding my hand over the top. This check only takes a moment and there's no extra equipment or movement of liquid to worry about.

If I make a small batch of fresh lye, I check the outside of the lye container by hand. When it's comfortably warm to the touch, it's good to go.

I'm not sure where I got my aversion to thermometers ... I think I exploded a glass one a long time ago (hmmm ... an infrared thermometer could be a lot of fun!).

 

[Kittish]

I do a heat check, if I've had to warm my oils, by holding my hand over the top. This check only takes a moment and there's no extra equipment or movement of liquid to worry about.

If I make a small batch of fresh lye, I check the outside of the lye container by hand. When it's comfortably warm to the touch, it's good to go.

I'm not sure where I got my aversion to thermometers ... I think I exploded a glass one a long time ago (hmmm ... a laser thermometer could be a lot of fun!).

I use an infra-red thermometer to check the temps of my oils and lye, just to make sure they're not too hot. It's got a laser dot that helps with aiming. Takes just a couple of seconds- pick it up, point and press the trigger button. Let go of the button and look at the readout.

And, I'll admit, it's kind of fun to play with. Can't get a really accurate reading of body temp, since the surface of your skin tends to be a couple of degrees cooler than core temp. But for taking surface temps it's really fun.

 

[SaltedFig]

Yes ... infrared thermometer indeed!

(changed track from levels to thermometers ... ooops )

 

[DeeAnna]

Be careful how you use IR thermometers. They only read surface temperature, so if you're wanting an accurate temperature of a liquid, be sure to stir it well before measuring the temp. If you measure the temp of a solid (like a loaf of soap while it's saponifying), then you're only going to learn the temp of the surface layer. Not too long ago, a soaper was having trouble with partial gel but insisted her soap didn't gel because her IR thermometer said the molded soap was just barely warm. She didn't realize what was going on ... but we got her set straight.

 

[reinbeau]

I use an infra-red thermometer to check the temps of my oils and lye, just to make sure they're not too hot. It's got a laser dot that helps with aiming. Takes just a couple of seconds- pick it up, point and press the trigger button. Let go of the button and look at the readout.

And, I'll admit, it's kind of fun to play with. Can't get a really accurate reading of body temp, since the surface of your skin tends to be a couple of degrees cooler than core temp. But for taking surface temps it's really fun.

The issue with this is your getting surface temp only. I stir while using my infrared, you'll get a better reading.

 

[Arimara]

Yes, that is exactly what I would expect. But it's still not a wise thing to do, if only to prevent the batter from tracing unexpectedly too fast.

That's why I'd only consider it for a HP castile, where I know what to expect with OO. I still would urge soapers to use discretion and caution. Hot lye and fast tracing oils can equal a disaster and to couple that with known heaters- you'd be asking for trouble. And since not everything is known about the other fatty acids that make up our oils as far as how they handle saponification, I can't say that I'd totally vouch for hot lye + cooler oils as a good/safe method.

 

[Kittish]

The issue with this is your getting surface temp only. I stir while using my infrared, you'll get a better reading.

I do give my oils a stir before I take their temp, but as long as the reading is within 5 degrees or so of the actual temp, it's all good. The lye solution I double check by feeling the bottom of my lye pot after I take its temp.

With it coming on winter here, I think I'm going to kick up my soaping temp by about 15 degrees, though, and mix closer to 130. I did that with the batch I made last night, and it came together really nicely.

 

[penelopejane]

I do a heat check, if I've had to warm my oils, by holding my hand over the top. This check only takes a moment and there's no extra equipment.

I'm not sure where I got my aversion to thermometers ... I think I exploded a glass one a long time ago (hmmm ... an infrared thermometer could be a lot of fun!).

Infrared thermometers make soaping fun and scientific! (I am sure!)
I measure everything from my mixes to the room where my wrapped soap gels.

If I'm having problems with soap it's invariably a temperature problem one way or another.

 

[IrishLass]

If I'm having problems with soap it's invariably a temperature problem one way or another.

Same here. I've found temps play a big part in how my formulas behave, such as whether I end up with stearic spots, and/or whether my soaps gel or not, etc...

I use my handy-dandy Thermapen thermometer to keep track of my oil and lye temps before they meet up.


IrishLass

 

[DeeAnna]

Thermapen rocks!!!! Whoo hoo! :mrgreen:

 

[SunRiseArts]

I agree with Kittish. And when I started making soap I was obsess with everything. But I have calm down.

If the temperature is 5 degrees off, is not a big deal. If one poured 1.1 oz of oil, instead in 1 oz, is ok. With lye, as long as it not passes the correct exact amount, is ok. If my lye measurement calls for 2.25, and I poured 2.1, is ok. I superfat at 2 or 3 % so I have lots of wiggle room.

 

[sarasvati]

There is one safety issue about temperatures I want to mention. I know it's an unlikely scenario, but someone posted on SMF about this exact issue not all that long ago. Apparently the soaper's crock pot was improperly heating the oils way too hot. I'd guess the temp of her fats at the time she started soaping was somewhere around 200 F (95 C) or more.

The soaper slowly poured cooler lye solution into this very hot fat. The lye solution naturally dropped to the bottom of the container and rapidly heated and turned into steam. The resulting geyser of steam blew hot lye and fat all over the kitchen. It was a minor miracle no one was hurt!

Moral of that experience -- do not add coolish lye to really hot fat! You'd be safer adding boiling hot lye to cool fat than the other way around, not that I'm recommending that either.

I know this is not the situation y'all are talking about here, but I thought it was worth mentioning. Sometimes people try some extreme methods (the "fluid hot process" method comes to mind) and problems do happen (like malfunctioning crock pots) so I thought it was worth mentioning that there are some outer limits to keep in mind.

This is great advice. Thank you!

 

[Arimara]

I don't think the person realized there was a problem until it was too late. Yes, cooling down the fats would be the solution if you caught the problem in time to make a correction.



Yes, that is exactly what I would expect. But it's still not a wise thing to do, if only to prevent the batter from tracing unexpectedly too fast.

I've since learned my lesson. Better to be safe and controlled (within reason) than to be sorry from recklessness.

 

[Richard Perrine]

As a newbie in soap-making, I have quickly learned to ignore the temp of my oils/lye as long as when I am ready to mix that the two are within 10-15-degrees of each other. Also, I wait until my lye/oil mixture is below 120 degrees before I quickly add the EO or natural FOs. I add my mica colors at hot temps as I don't feel it make any difference.

 

[Lin19687]

Again.......... it also depends on your recipe. I can't do RT, but I have used 140 oils and 85 Lye no issue.

Trial and error happens as you learn. And if you are set on one recipe you will figure out what will NOT work quickly.

ALSO remember that if your FO has a FLASHPOINT, you BETTER know what it is to be on the safe side.
If I have a FO that has a FP of around 150, then I try to soap cooler at 120 or 110

 

[DeeAnna]

Flash point is the temperature at which the vapor will burn if exposed to open flame. If you're a fire fighter or emergency response person, it's important to know these things to properly respond to spills and fires. If you're a supplier, you need to know these things to ship properly. As a soaper, unless you cook your soap over open flame, knowing the flash point is honestly not all that critical from a safety point of view.

Many soapers use the flash point as an indicator of volatility (how fast the scent evaporates), and that's not correct at all. If you really want to know which scents evaporate quickest, the property you want to know is the vapor pressure, not the flash point.

To control the loss of scent, then add it at the lowest possible temperature that's reasonable for what you're doing and minimize the time at which the scent is at a warm/hot temperature. This advice holds true for all scents, regardless of flash point.

 

[yearomare]

There is one safety issue about temperatures I want to mention. I know it's an unlikely scenario, but someone posted on SMF about this exact issue not all that long ago. Apparently the soaper's crock pot was improperly heating the oils way too hot. I'd guess the temp of her fats at the time she started soaping was somewhere around 200 F (95 C) or more.

The soaper slowly poured cooler lye solution into this very hot fat. The lye solution naturally dropped to the bottom of the container and rapidly heated and turned into steam. The resulting geyser of steam blew hot lye and fat all over the kitchen. It was a minor miracle no one was hurt!

Moral of that experience -- do not add coolish lye to really hot fat! You'd be safer adding boiling hot lye to cool fat than the other way around, not that I'm recommending that either.

I know this is not the situation y'all are talking about here, but I thought it was worth mentioning. Sometimes people try some extreme methods (the "fluid hot process" method comes to mind) and problems do happen (like malfunctioning crock pots) so I thought it was worth mentioning that there are some outer limits to keep in mind.

I did this very same thing today (added cooled lye to hot oils in my crock pot) and I could not get emulsification no matter how much I stick blended the stuff. Fortunately I did not get the geyser of steam that was mentioned here. I thought it might not be the brightest of ideas, and I totally should have known better, but I decided to give it a try. Lesson learned, I had to throw the whole mess away. Next time I get a bright idea (not!) like this I will come to this forum first, like I should have done today.

 

[shunt2011]

I did this very same thing today (added cooled lye to hot oils in my crock pot) and I could not get emulsification no matter how much I stick blended the stuff. Fortunately I did not get the geyser of steam that was mentioned here. I thought it might not be the brightest of ideas, and I totally should have known better, but I decided to give it a try. Lesson learned, I had to throw the whole mess away. Next time I get a bright idea (not!) like this I will come to this forum first, like I should have done today.

There was something else going on. Using cool lye into warmer oils is not the problem. I sometimes add room temp lye to oils at 110 or a bit warmer. Never had a problem.

 

[Richard Perrine]

There was something else going on. Using cool lye into warmer oils is not the problem. I sometimes add room temp lye to oils at 110 or a bit warmer. Never had a problem.

I agree. I routinely use room temp lye solution in hot oils with no problems.

 

[DeeAnna]

@yearomare -- I agree with Shari and Richard. Once the lye and fats are combined, the temperature of the resulting mixture is all that applies. Whether your lye solution was warmer than the fats or vice versa -- this is simply not an issue after these ingredients are mixed together. If your batter didn't emulsify, there is something else amiss.

The geyser thing will only happen if your fat temperature is near or above the boiling point of the water in the lye solution. This is very unlikely to happen. If you're fats were somewhat hotter than your lye solution, but not that hot, nothing bad is going to happen. I don't want people to get overly anxious about this issue, because it's only going to be an issue in unusual situations. Like I said in my earlier post, "... Sometimes people try some extreme methods (the "fluid hot process" method comes to mind) and problems do happen (like malfunctioning crock pots) so I thought it was worth mentioning that there are some outer limits to keep in mind...."