Newbie: Lye temperature reccomendations?

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mikvahnrose

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I have made a few batches of soap and read that the lye and oils have to be around 120 degrees farenheit. So i have stuck in that range for fear of making bad batches. All of my soaps so far went really well but i am now seeing that people make soaps at different temperatures.

Like just now i wanted to know how to make soap with goats milk or milk in general, and people say the lye has to be chilled.
So my question is, can the lye temperature actually be room temperature to still make soap? I figured it was the heat that sorta "mends" the oils and lye mix together.

How does the temperature of the lye affect the soap? I know hotter lye/oil can gel the soap (which i did on accident once.)

But how does cold lye solution work. Does a cold lye solution also slow down trace?

Thank you
 
Yes it can be room temperature and many of us masterbatch our lye solution so it is always room temp when soaping with it. For milk soaps you can mix your lye 50/50 water to lye or even higher with the water. Then add the balance of liquid with the milk. When doing this method I like to add the milk in after adding the lye slowly to your batter. Milk heats batter, especially goat's milk. If you want to make milk your 100% liquid I find it best to freeze the milk solid, put the pitcher you will be mixing in in an ice batch then start mixing the lye and milk by pouring some of the lye over the milk cubes, stir then repeat process until fully mixed. Do keep it in an ice batch the entire time. Milks especially goat's milk will overheat and turn dark orange if you add lye directly even to cold milk.

As for gelling, if you do not want your soap to gel put it in the fridge or freezer. The higher liquid use in soap the hotter the gel, so with milk soaps they are best if put in the freezer. I personally would start out with using less milk and adding it after the lye solution meets the oils, as mentioned above.

Lye that is to hot mixed with an ingredient that contains sugars can actually cause a nasty volcano. I never soap with lye hotter than room temp and your oils and lye do not need to be the same temp. Just do not use hot oil, heat accelerates trace and the risk of overheating and volcanoes, on the other side of the fence chilled or cold oils, when using lard or tallow can cause a false trace where the soap thicken quickly and you think you have trace. As soon as the lye heats it up it can liquefy and separate.

There is a definite learning curve to soap, but it is sure addicting. I would get a few batches under my belt before trying Goat's Milk Soap.
 
Wow thank you!
So you are saying that lye and oils can be different temps as in
have room temperature lye
and heated oils? But the oils can't be ((too)) hot?

So what would be a good range in temperature of your oils when mixing with your master batch lye solution. And how does that affect the time to get to trace? Because everything i have read is have the oil be the same(ish) temperature as the lye solution.
 
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The cooler everything is, the longer trace will take, generally speaking. Saponification generates and is also increased by heat, so by soaping colder you are not helping your soap along with the heat so it will take longer to get started. As it saponifies, it can gel or partially gel the soap as it warms up.

Many people use room temperature lye and the oils that are touchable but not too cold.

Others still use the heat transfer method, where the hot lye solutions is allowed to cool, rather poured over the unmelted oils so that they melt in the heat of the lye solution. So many options!

But for milks, as Carolyn said, you want to keep things colder if possible.
 
"...everything i have read is have the oil be the same(ish) temperature as the lye solution. ..."

There are a lot of ideas that seem to make "common sense", but actually make soaping more complicated than it needs to be. This rule is one of them. It might have been created to keep beginning soapers out of major trouble, but then it took on a life of its own.

Think about it -- when the lye solution at one temperature and fats at another temp are mixed, the mixture quickly evens out to a temp somewhere in the middle, no matter what temp each one was to start with. The average temperature of the batter just needs to be not overly warm for the purposes you have in mind. That means, within reason, the ingredients can be at any starting temperature and they will still make good soap. Cool lye, warm fats. Vice versa. Warm lye, warm fats. Cool lye, cool fats. Etc.

Once you start making soap with ingredients that are temperature sensitive or want to use more complicated decorative techniques, then you do have to think about what you need to do to respect the requirements of that ingredient or technique.

Milk soap is one example -- it needs to be soaped cooler as the others are advising.
A soap with beeswax or stearic acid is another -- the batter needs to be quite warm.
A soap with a high % of lard, tallow or palm needs to be somewhat warmer than a soap with a smaller % of these solid fats.
A soap with a fancy design probably needs to be soaped on the cooler side.
 
Wow thank you!
So you are saying that lye and oils can be different temps as in
have room temperature lye
and heated oils? But the oils can't be ((too)) hot?

So what would be a good range in temperature of your oils when mixing with your master batch lye solution. And how does that affect the time to get to trace? Because everything i have read is have the oil be the same(ish) temperature as the lye solution.

That rule does appear in lots of places! But I think it's a rule that has been taken out of context. I think the rule was something like "oils and lye should be within 100-120 degrees" and people took that too far.

As far as temp - IMO, cooler is generally better than hotter. It's easy to fix a mistake made if your oils and lye are too cool - but too hot lye and oils can cause what we call "volcanoing". That's when heat builds up in the center of the log of soap. If you see the middle of your soap start to bulge upwards and form cracks along the top, that's the beginning. If you see that, get in there and stir stir stir! Stirring releases the trapped heat. If you don't release the heat, it will continue to build. Your soap may overflow your mold or in some very very dramatic cases, spew (like a volcano). It may also separate. These things are messy and unsafe.

If your soap batter is too cool, you can put the pot on gentle heat on the stove. See how much easier that is? :)

IMO, 120 is on the high side. I really like 100ish degrees.
 
I have gotten to the point I rarely take the temp of my stuff anymore.

I master batch my lye at 50% concentration. I make up the rest of my liquid with aloe juice. I heat my oils just until they are clear, since I use either lard or palm as my main oil. If the oils look cloudy they are starting to solidify and could cause false trace.
 
I started off soaping by checking temps too. Many of us do. I eventually switched to room temp soaping because things move a little slower, and that's usually a good thing, by soaping standards. If I'm planning to soap tomorrow, I try to make my lye solution today, and let it sit, covered, until tomorrow, so that it's fully at room temp. If I make the lye today, then that's one step out of the way for tomorrow, and all I have to think about is the oils. Then tomorrow, I would melt my solid oils and butters til just melted, add my olive oil, and feel the side of the stainless steel pot with the palm of my hand. This is one reason why I like using SS, because you can get a good idea of the temp by feeling it. I start to soap when it's just warm to the touch. One thing to watch for with room temp soaping is that your oils cool off so much that they start to solidify. If that happens, warm them just enough to liquefy everything before adding the lye, and you're good to go! There are many different ways to soap, and eventually you'll find the one that fits you best. :grin:

P.S. When melting your oils, you should aim to heat them just enough to melt them, you don't want to get them HOT, just melted. They should be clear, not cloudy, but they don't need to be hot.
 
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When I started making soap I tried to keep oil and lye at about 115-125 degrees. Now I soap at 85 degrees with oil and lye within 7 or so degrees of each other. I don't get too crazy about so it could be anywhere from 75-90 degrees. With my fast tracing fo's it is always at least 85 or cooler. I need time for all my swirls!
 
This thread has been super informative and i never would have thought you can "master batch" your lye solution. Honestly that sounds a lot easier.

But..How do you guys go about that? Ratio wise? I read one has 50/50 so is that 50 lye 50 water? That looks super concentrated. How much lye to water is needed in percentages. I have been using oz method on Brambleberry but switching to % to be able to scale up and down a recipe.

Is your solution kept at a measurements of the way you like to possibly superfat your soaps too? I like to superfat my soap around 5%.

Thank you!
 
A 50:50 solution of NaOH is a mixture of 50% NaOH and 50% water by weight.

Is your solution kept at a measurements of the way you like to possibly superfat your soaps too?...

I don't quite understand what you mean. Taking a stab at some kind of answer --

I make a bunch of lye solution ahead of the time I want to soap. I make more than enough for several typical recipes. It doesn't matter what the superfat is -- I just make a bunch of lye solution and use it up.

When I want to make soap, I weigh the correct amount of lye solution for the recipe I want to make. If my recipe calls for 100 g of NaOH, then I weigh out 200 g of NaOH solution if it is at 50% concentration. If you always use a particular NaOH concentration -- say 33% for example -- then you can make a master batch of 33% NaOH solution rather than 50%.

Any lye solution used for soaping is highly concentrated and should be treated with the same level of safety equipment and respect. Frankly, a 28% NaOH solution will do just as much damage in the eyes just as quickly as a 50% solution. Only when the lye concentration drops well below 10% NaOH does the danger level start to drop off.
 
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When I want to make soap, I weigh the correct amount of lye solution for the recipe I want to make. If my recipe calls for 100 g of NaOH, then I weigh out 200 g of NaOH solution if it is at 50% concentration. If you always use a particular NaOH concentration -- say 33% for example -- then you can make a master batch of 33% NaOH solution rather than 50%.

Yes that is what i meant for superfatting. I was thinking that for superfatting there is lye discount rather than water discount, yes?

So as far as concentration goes, is 33% the standard? Because you mentioned that a 50% concentration would call double the amount of solution. Why is that? Would 33% call for triple the amount? Sorry if i am bombarding with all these questions!
 
There is no standard for lye concentration. It can safely range from about 25% to about 50%. Not all of the NaOH will dissolve at concentrations above 50%, so you cannot go higher than that. Concentrations below about 28% should be avoided for cold process soap making, but hot process soap is often made with a 25% NaOH solution. I would say the normal range for cold process soap making is from 28% to 40%. I'd say the most commonly used concentrations that people mention they use are from 28% to 33%.

Lye discount and superfat are roughly the same idea. Water discount is totally different.

"...a 50% concentration would call double the amount of solution. Why is that? Would 33% call for triple the amount?..."

An NaOH solution that is at a 50% concentration contains 1 gram of water for every 1 gram of NaOH. If you measure out 100 grams of 50% solution, only 50 grams of that is actual NaOH.

An NaOH solution that is at a 33% concentration contains 2 grams of water for ever 1 gram of NaOH. If you measure out 100 grams of 33% solution, only 33 grams of that is actual NaOH.

Edit -- At this point in your soaping career, I think it would be best if you don't masterbatch your lye. I get the feeling you need the practice and structure of making lye solution from scratch. When you get more experience, masterbatching is nice. But not at first when you're still figuring out the math and methods.
 
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An NaOH solution that is at a 50% concentration contains 1 gram of water for every 1 gram of NaOH. If you measure out 100 grams of 50% solution, only 50 grams of that is actual NaOH.

An NaOH solution that is at a 33% concentration contains 2 grams of water for ever 1 gram of NaOH. If you measure out 100 grams of 33% solution, only 33 grams of that is actual NaOH.


I am starting to get it. There is just certain things i have read on this thread that is a bit contradicting (i think?). Hold up lemme find the quotes.

For milk soaps you can mix your lye 50/50 water to lye or even higher with the water. Then add the balance of liquid with the milk.

I have gotten to the point I rarely take the temp of my stuff anymore.

I master batch my lye at 50% concentration. I make up the rest of my liquid with aloe juice.

Here they have a 50/50 concentration. So as you say for every gram of lye is one gram of water. I get that now. If the recipe calls for this amount of lye, and your batch is 50% concentration; keep adding until the amount of lye is equivalent to what is needed.

What i don't get is like when they "make up the rest" of the liquid with milk or aloe (like examples given above). If the rest of the liquid (say aloe) doesnt have lye in it, wouldn't the concentration of lye be even lower since you are "diluting" it with more liquid (the aloe)

I hope you are following me (i feel like im confusing myself lol) By your logic, if the recipe calls for 100 gm of lye and you double the amount (because it 50% concentration), how do you formulate a proper amount of lye solution when adding a different liquid (aloe/milk/whatever) after the fact?

OR is that where the water discounting comes into play? To make up for the milk being added. So if your recipe calls 50% milk, 50% water. Should the water to lye ratio be even more concentrated since later on it will be diluted with milk? This is what is troubling me.


I AM SO SORRY. For all these questions. But they are bound to come around sooner or later and eventually i will have to dive in and just do it. So i figure i might as well understand it now than get stuck in a "bad habit" of doing things an odd mathematical way.
Thank you and i hope i am not asking too many questions. I know i am, but i am really interested in getting this right.
 
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I am starting to get it. There is just certain things i have read on this thread that is a bit contradicting (i think?). Hold up lemme find the quotes.

Here they have a 50/50 concentration. So as you say for every gram of lye is one gram of water. I get that now. If the recipe calls for this amount of lye, and your batch is 50% concentration; keep adding until the amount of lye is equivalent to what is needed.

What i don't get is like when they "make up the rest" of the liquid with milk or aloe (like examples given above). If the rest of the liquid (say aloe) doesnt have lye in it, wouldn't the concentration of lye be even lower since you are "diluting" it with more liquid (the aloe)

I hope you are following me (i feel like im confusing myself lol) By your logic, if the recipe calls for 100 gm of lye and you double the amount (because it 50% concentration), how do you formulate a proper amount of lye solution when adding a different liquid (aloe/milk/whatever) after the fact?

OR is that where the water discounting comes into play? To make up for the milk being added. So if your recipe calls 50% milk, 50% water. Should the water to lye ratio be even more concentrated since later on it will be diluted with milk? This is what is troubling me.


I AM SO SORRY. For all these questions. But they are bound to come around sooner or later and eventually i will have to dive in and just do it. So i figure i might as well understand it now than get stuck in a "bad habit" of doing things an odd mathematical way.
Thank you and i hope i am not asking too many questions. I know i am, but i am really interested in getting this right.


First, in the beginning masterbatching lye might be to complex. Get comfortable making CP soap first.

After you have done a few batches or made soap for a few months or 6 months or more, if infrequently, then give master batching a go.

To answer the questions, though. Say you run your recipe through soapcalc ir soapee or whatever lye calculator you are using 33% lye solution and you indicate your SF, and plug in your oils. The lye calculator tells you how much water and how much lye you need to get that 33% lye solution.

This is where you do your math. You have a 50% lye solution already. So you double the NaOH weight to get the right amount of lye. THEN you deduct the that amount from your total of water and lye as indicated by your lye calculator and THAT is the remaining amount of liquid needed.

That remaining amount of liquid is what they mean by 'make up the rest.'

Here is an example recipe using soapee for a Castile soap:

500 g Olive Oil
130.6 g Total Water Weight
64.3 g Total NaOH Weight
15g Fragrance Oil Weight
Total Batch Weight 709.9g
Superfat 5%
Lye Concentration 33%

To get 33% lye concentration using a 50% lye master batch and additional liquid:

Total lye + water weight (64.3g + 130.6g = 194.9g)
(Minus) - Total weight 50% lye masterbatch (2 x 64.3g = 128.6g)
(equals) = Remaining liquid needed (194.9g - 128.6g = 66.3g)

So if you were making straight castile soap you would add in another 66.3g water to the measured out amount of your masterbatch.

Or if you wanted to make a milk castile, you would add 66.3g of milk to the lye solution. Or whatever OTHER liquid. That is 'making up the rest' as referred to by previous poster.
 
No. You are right. I master batch my lye at 50% concentration, and store it in a plastic jug.

When I make soap, however, I want to use a 33% concentrate. So, I put my oils in the calculator. It tells me I need X amount of lye. So I pour twice the amount of my master batch lye. This gets me x amount of lye and x amount of water.

Then I measure out X amount of aloe juice. This gets combined with my lye. So now I have my 33% lye, 1 part is water, 1 part is aloe and 1 part is NaOH.
 
Let's say you want to make a soap and use a 33% water amount. You have a master batched solution at 55% (because you don't always use one specific solution strength when soaping).

You add in the 50% solution until you have enough NaOH in there. But you don't have enough liquid yet - you're at a 50% strength still. Do then you add in a liquid until the amount liquid and NaOH is at a 33% solution strength. In the examples above, people were using liquids other than water, but I have done this with water before. I add in my master batch and then some more water until the water amount works for my recipe

Edit. Many questions is good. Just also be sure to check to see which topics are already currently open, try not to hijack other threads with a new question and don't ask the same question in many different posts. We love answering questions, but ideally when the way they are asked is nice and friendly - which they are so far [emoji106]
 
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"...What i don't get is like when they "make up the rest" of the liquid with milk or aloe (like examples given above). If the rest of the liquid (say aloe) doesnt have lye in it, wouldn't the concentration of lye be even lower since you are "diluting" it with more liquid (the aloe)..."

Yes, that is correct. You've gotten good explanations from three competent soap makers, so hopefully you're making sense of it all now!

"...OR is that where the water discounting comes into play?..."

Not really. Water discounting isn't directly related to the use of masterbatched lye. Here is what the terms "water discount" and "full water" mean to most people most of the time --

"Full water" means a soap recipe that uses an NaOH solution at roughly 28% NaOH concentration. This 28% concentration is supposedly the "normal" amount of water for making soap (although it's really not). If you use a more concentrated lye solution than that -- say 33% lye concentration for example -- then you are "water discounting" or using "less than full water" to make your soap.

It makes no difference how you make the lye solution -- you can make it by mixing water and solid NaOH or you can make it from a masterbatched lye solution. The essential point is "full water" is about 28% lye concentration and "discounted water" is a more concentrated lye solution.

I personally think terms "water discount" and "full water" have no truly useful purpose, but they are firmly part of soap making lingo, so I live with 'em.
 
Thank you guys! You all have been so helpful and i finally get it now! You pour in the extra amount of liquid to get to the concentration you need. The 50% is the "stock" but you correct the concentration at time of usage. k
chaystack probably described it the easiest way possible for me to visualize it. But i will learn that formula Susan as it is likely an essential component to know.

Once again, thanks for being so patient with me and putting up with my oddly described questions :3
 
I am going to reiterate what a couple of people have said above. Please make soap for at least 6-9 months before trying to masterbatch. Why, you ask? Because you need to figure out which concentration would work best for you. You need to know if you prefer 28% or 33%. And, indeed, if you want to masterbatch at all. I don't. I would much prefer to store dry NaOH then add the liquid of my choice than to store a jug of lye water.
 
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