sap value of essential oils?

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I do not, but I do know that one doesn't need to account for the SAP value of essential oils when calculating the lye. Not all of them are even saponifiable.
 
@AliOop just wondering, because I was recalculating things with the calculator from internet. And when I added in the % of oil scent the lye amount raised. So whats the reason then they add more lye in when it doesn't saponify?
 
Interesting! Did you enter the lavender EO as a soapmaking oil, or under the fragrance box? It should go in the fragrance box, and doesn't normally change the lye amount.
 
@Megan I found this on the internet: The carrier oils used in aromatherapy normally contain unsaturated fatty acids (except palm and coconut oils which are high in saturated fat) and are mostly poly-unsaturated fatty acids. Examples of these fatty acids are linoleic, linolenic and arachidonic acid - all of them being essential fatty acids.
 
@Megan I found this on the internet: The carrier oils used in aromatherapy normally contain unsaturated fatty acids (except palm and coconut oils which are high in saturated fat) and are mostly poly-unsaturated fatty acids. Examples of these fatty acids are linoleic, linolenic and arachidonic acid - all of them being essential fatty acids.
That is talking about carrier oils (usually coconut, olive, sweet almond, etc.) for the EOs - not the actual EOs.
 
@AliOop okay so not the pure distilled oil...
Correct :)

@AliOop I typed in the 5 % oil weight and when I change this to 0 it changed the lye amount downwards so less lye in the recipe.
Very interesting. I'm sure there is a reason for it, but I don't know why, unless perhaps they are using an average amount of carrier oil that might be contained in fragrance oils, as opposed to essential oils. You can post this question in the SMFr help forum and see if one of the admins can explain why this would happen:

https://www.soapmakingforum.com/forums/soapmakingfriend-com-support-forum.50/
 
@Megan I found this on the internet: The carrier oils used in aromatherapy normally contain unsaturated fatty acids (except palm and coconut oils which are high in saturated fat) and are mostly poly-unsaturated fatty acids. Examples of these fatty acids are linoleic, linolenic and arachidonic acid - all of them being essential fatty acids.
that's probably from adulterated EO's. If you buy/use pure essential oils, (which most soapmakers use) they will not have any carrier oils in them.

That is talking about carrier oils (usually coconut, olive, sweet almond, etc.) for the EOs - not the actual EOs.
haha we were typing at the same time.
 
@AliOop I typed in the 5 % oil weight and when I change this to 0 it changed the lye amount downwards so less lye in the recipe.

Please recheck this because I really don't see how this could happen.

Maybe you inadvertently changed the superfat perhaps? That setting is in Section 4.

I mocked up a recipe and changed the % of fragrance in Section 7 from zero to several other values. The NaOH weight did not change, no matter what the fragrance percentage was.
 
keeps changing, I tell you what I did so you can check it too if you want.

1) solid soap
2) percentages by total size 2000 grams
3) lye concentration 33,3
4) superfat 5 %
5) selecting oils as following: lard 40%, olive oil 35% coconut oil 25 %
6) sugar 3 teaspoons
7) 8% of oil weight also filled in the fragrances tab
8) notes somethings about the sugar I added

this is it and keeps changing
 
2) percentages by total size 2000 grams
I wonder if it is changing the lye value because of the setting that you want a batch only totaling 2000g? It makes sense that once you add/remove the EO, that it will adjust the oil and lye qty to make up for the EO that add/remove so that the batch size always remains 2000g.

*Note I have not checked this with the friend calc, as I don't use it. Just a guess based on reading the posts.
 
"...percentages by total size 2000 grams..."

This is the problem child.

The rest of us are using 2000 grams of oils, which I'd say is the more common way to calculate a recipe. There's nothing wrong with your approach, but constraining the total weight rather than the fat weight definitely alters how the calculator functions.

There's no sap value for EOs -- the changes in the recipe you're seeing have nothing to do with this. The "problem" is created by the mathematical gyrations required to keep the total batch size constant.

As you increase the % of EO in the batch, the rest of the ingredients have to be reduced to keep the total batch weight constant. And vice versa -- less EO means less fragrance weight so the weights of the other ingredients have to be increased.
 
Just wanted to chime in and add that unlike carrier oils, EOs are volatile oils, i.e. they evaporate. Depending on the EO, they evaporate at different speeds - that's why perfumes have top-middle-base notes, and why getting aromas to "stick" in soap can be challenging.
As many know, top notes evaporate the quickest, e.g. citrus, etc., middle notes are slower e.g. geranium, lavender, etc.), base notes last the longest and are often fixatives - they can prolong the evaporation rate and boost the strength of other notes in the composition e.g. patchouli, vanilla, frankincense, etc.
But there's a lot of interpretive flexibility here. Ylang ylang, for me, is somewhere between a middle and base note - especially in soap, while jasmine, which is often listed as a middle note, is a pretty damn robust aroma...but moreso in perfume than in soap. And then some middle notes can prolong certain top notes and vice versa. But the general principle holds. Seasoned noses use variations in volatility to their advantage. Before the advent of aromachemicals, the old school noses were so attuned as to be able to identify where the EO was grown. Give them three different vials of frankincense, they could tell which came from Kenya, which came from Somalia, and which came from Morocco (maybe a bad example, because those three are relatively distinguishable once you've had a chance to compare them, but you know what I'm saying).
Some EOs are changed by saponification - I remember Kevin Dunn saying something about lavender being one of the only EOs that actually gets stronger after saponification, while a lot of them just evaporate before you can even cut the soap (I'm looking at you, white grapefruit).
But no pure EOs can used as a carrier oil. As mentioned above - they don't have fatty acids.
 
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