Geek tip -- Why should you NOT use "full water" in your recipes?
Many
soap recipe calculators have a default "full water" setting of "38% water as % of oils", and that's what a lot of cold process (CP) soapers use. Many do so because they don't realize there are benefits from using less water. Or perhaps a soaping teacher or adviser has mysteriously cautioned against the perils of using "discounted water" recipes.
I would like to encourage you to try a bit less water when you make CP soap next time, and see what you think.
Why would you want to use less water? Here are some reasons:
... harder soap at the time of unmolding so you can unmold and cut sooner
... batter is faster to come to trace, which is nice for simple recipes or doing higher volume production
... faster rate of saponification which is good for recipes high in unsaturated fats (castile being the prime example)
... less chance of emulsion failure (separation) in the mold
... less likely for the soap to go into gel on its own (less need for fans, fridge, or freezer!)
... less likely to show streaking or mottling (aka glycerin rivers)
That said, a little extra water can sometimes be helpful. Here are some reasons for using more water --
... slower rate of saponification which is good for recipes high in lauric and myristic acids (100% coconut oil being the prime example)
... taming naughty floral and spice fragrances that want to accelerate trace
... batter is slower to come to trace for fancy decorative swirls and such
... more likely for the soap to go into full gel on its own
I will explain how to use less water in the next Geek Tip -- it's pretty simple!
Geek tip -- How to calculate a recipe with less water
As I said before, many
soap recipe calculators are set to a default of 38% water as % of oils.
To use less water, I encourage you to change from "water as % of oils" to "lye concentration" and things will be much much easier and more consistent. Pull up your favorite
soap calculator and figure out how to do that. For example, in
SoapCalc and in
Soapee, these settings are contained in Section 3. Click in the round circle to the left of "lye concentration" to change from "water as % of oils" to concentration. Simple!
Next, think about the soap you are planning. When you used the default of 38% water as % of oils, you were creating recipes that used an average lye concentration of about 28%. To make a recipe that uses less water, you will want to make the lye more concentrated -- in other words, you will want to type a larger number for the concentration.
I suggest you try a 30% lye concentration for your first experience and see what you think. I know -- a change of just 2% doesn't seem like much, but trust me -- a small change in lye concentration can make a definite difference in how your soap behaves. Don't go overboard!
As you get some experience with using less water, you'll soon figure out what basic lye concentration works best for your recipes and your soaping style. Once you find that sweet spot, then you can deliberately vary the lye concentration a bit to best work with various recipes, decorative techniques, accelerating fragrances, and different additives.
I will give you some numbers that work well for me and the way I soap. Pretty much all of my cold process (CP) soaps are made with 30% to 33% lye concentration. If I want extra time for swirling or if I am using a naughty fragrance, I'll choose a 30% to 31% lye concentration. For a soap without any fancy stuff or for a recipe that naturally moves slowly, I would likely use 33%.
There are exceptions to my general rules of thumb --
... For a castile (100% olive oil) CP soap, I would use a 40% lye concentration to encourage the soap to trace faster
... For hot process (HP) soaps and liquid soaps (LS), I would use 25% lye concentration to allow for water evaporation and easier handling
Remember -- just a percent or two change in the lye concentration can definitely change how a soap recipe behaves. So you do not need to make big changes in the lye concentration to see definite differences.
For more information about using lye concentration rather than "water as % of oils", please see this thread:
http://www.soapmakingforum.com/showthread.php?t=54095
...and a related discussion about why curing is not just about evaporation that morphs into a discussion of water content:
http://www.soapmakingforum.com/showthread.php?t=56363
...and finally this detailed discussion:
http://www.soapmakingforum.com/showthread.php?t=53642
Geek Tip -- What are the SoapCalc numbers?
I've posted this elsewhere, but I'm adding this info to this thread too--
When evaluating a soap recipe, you can look at the individual amounts of each fatty acid (myristic, lauric, stearic, palmitic, oleic, ricinoleic, linoleic, linolenic, etc) to determine the effect of each fatty acid on the soap ... or you can use the SoapCalc "numbers" to do much the same thing.
Unfortunately beginning soapers often get confused because the names of the SoapCalc numbers are rather misleading. Another thing beginning soapers do is endlessly tweak a recipe to get certain numbers "just right." The thing to remember is
the fatty acid profile and the SoapCalc numbers are just guidelines. They do not account for how the soap is made -- hot process, cold process, and all the variations. They do not account for the effect of superfat, water content, or cure time. And they do not account for the effect of any additives (sugar, milk, honey, sodium lactate, etc.)
I want to show you how the SoapCalc "numbers" are calculated, so you can use these numbers more effectively. To keep this explanation simple, I am going to choose a single fat -- cocoa butter -- and pretend as if I am going to make a soap from this fat.
Cocoa butter has a fatty acid profile that looks something like this:
Lauric 0
Myristic 0
Palmitic 25-35% (average is about 30%)
Stearic 28-38% (average is about 33%)
Ricinoleic 0
Oleic 29-41% (average is about 36%)
Linoleic 2-7% (average is about 4%)
Linolenic 0
Lots of numbers, right? Let's look at how SoapCalc groups those numbers into fewer bits of useful information:
Hardness 61
Cleansing 0
Condition 38
Bubbly 0
Creamy 61
So now, okay, how does a person translate from the fatty acid profile to the Soapcalc numbers? Here's how:
Hardness: The hardness value is the sum of Lauric + Myristic + Palmitic + Stearic acids.
These are the saturated fatty acids. The Hardness number is a measure of the physical hardness-like-a-rock. It tells you how relatively easy it will be to unmold a particular soap after saponification. It does NOT necessarily tell you how long-lived the soap will be -- I'll get to that in a bit.
Hardness number from the fatty acid profile (above) = 0% + 0% + 30% + 33% = 63%.
Soapcalc Hardness = 61%.
Is the difference between 63% and 61% important? Nope, not too much. Keep in mind that any fatty acid profile for any particular fat is only an estimate. The SoapCalc folks calculated their Hardness number from slightly different data than we are using. Bottom line -- don't agonize over differences of a few percentage points.
Cleansing: The cleansing value is the sum of Lauric + Myristic acids.
It is a measure of how water soluble the soap is -- meaning it is a measure of how easily the soap dissolves in difficult situations such as hard water, cold water, or salt water. The Cleansing number does NOT tell you whether the soap will actually get your skin clean, which is the usual misinterpretation of the Cleansing number. A soap with a Cleansing value of zero will clean your skin; it is just not as water soluble in hard/cold/salty water as a soap with a high Cleansing value.
The cleansing value is also a rough measure of how harsh the soap may be to the skin. The more lauric acid there is in the soap, the higher the cleansing value will be and the more likely the soap will be drying or irritating. People with sensitive or damaged skin are more likely to react to a soap with a high cleansing value than people with normal skin. That is a big reason why some folks are fine with 30% coconut oil in their soap recipes and others shudder at the thought of any coconut oil at all in their soap. Most of us fall somewhere in the middle, based on what many soapers report.
Cleansing number from the fatty acid profile = 0% + 0% = 0%
SoapCalc Cleansing = 0%
Conditioning: The conditioning value is the sum of Oleic + Ricinoleic + Linoleic + Linolenic acids.
These are the monounsaturated and polyunsaturated fatty acids. As the conditioning value goes up, the cleansing value goes down, and vice versa. Since the two are closely related, I focus on the cleansing value, since it has more influence on how my skin feels after bathing. I do not pay too much attention to the conditioning value.
Conditioning number from the fatty acid profile = 0% + 36% + 4% + 0% = 40%
SoapCalc Conditioning = 38%
Bubbly: The Bubbly value is the sum of the Lauric + Myristic + Ricinoleic acids.
This is a measure of how much loose, fluffy lather is produced. A "bubbly" lather is produced quickly by a soap, but doesn't last long.
Remember that the first two fatty acids make a soap that is very soluble in water, so it makes sense that a soap that has a lot of these two fatty acids would make lots of lather, right?
Ricinoleic acid does not make soap that lathers well on its own, but combined with other fatty acids, it enhances the lather the other fatty acids produce. Does a low or zero Bubbly number mean the soap doesn't lather at all? Nope -- just that the soap might not have a lot of fluffy big bubbles.
Bubbly number from the fatty acid profile = 0% + 0% + 0% = 0%
SoapCalc Bubbly = 0%
Creamy: The Creamy value is the sum of the Palmitic + Stearic + Ricinoleic acids.
Palmitic and stearic are the fatty acids that produce lather that is fine textured (like whipped cream) and longer lived. Ricinoleic, as mentioned before, enhances lather, whether it be big, bubbly lather or dense, creamy lather.
Creamy number from the fatty acid profile = 30% + 33% = 63%
SoapCalc Creamy number = 61%
Long life: The longevity of a soap is the sum of the Palmitic + Stearic acids.
Palmitic and stearic acids create a soap that is relatively hard and relatively insoluble in water.
Long-lasting number from the fatty acid profile = 30% + 33% = 63%
SoapCalc Long-lasting number = ???
I said I'd get back to this issue. SoapCalc numbers do not directly measure longevity. Many people confuse the Hardness number as being a measure of how long lived the soap is, but that is not strictly correct. If you are working in SoapCalc, the fastest way to estimate the Long-lasting number is this:
SoapCalc Long-lasting number = Hardness number - Cleansing number
For cocoa butter, it's a no-brainer -- the Hardness number is the same as the Long-lasting number. For a Coconut Oil soap, the story is quite different:
Hardness = 79
Cleansing = 67
Long-lasting = 79 - 67 = 12
Compare that to 63 for cocoa butter. Bottom line -- a coconut oil soap will not last nearly as long as a cocoa butter soap, all other things being equal.