FA Profiles in Soap Calculators: Who Copies Whom?

Soapmaking Forum

Help Support Soapmaking Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

ResolvableOwl

Notorious Lyear
Joined
Jan 14, 2021
Messages
2,571
Reaction score
6,980
Location
Germany
Since basically I learned that there are several soap calculators out there, I've been a bit surprised how they are agreeing on the actual numbers of the respective fatty acids.

Linoleic - Oleic - Palmitic - Stearic

52 - 18 - 13 - 13
Soapee Next
52 - 18 - 13 - 13 SoapCalc
52 - 18 - 13 - 13 Lye Calculator & Recipe Creator for Soap Making | LyeCalc
52 - 18 - 13 - 13 Soapmaking Recipe Builder & Lye Calculator
53.6 - 18.6 - 13.4 - 13.4 Soap recipe and lye calculator

Now I'm scratching my head when comparing these with non-soapy sources:

42 - 35 - 20 - 2 Fatty Acid Composition Of Some Major Oils
52.5 - 17.2 - 23.9 - 2.5 https://www.cotton.org/journal/2010-14/2/upload/JCS14-64.pdf

Particularly that last article is an awesome resource that discusses in great length how little can be changed in the fatty acid profile by breeding and growth climate.

I mean, we're putting more or less blind faith into the correctness of these numbers. But then it looks like someone was too lazy to look up the individual numbers for palmitic and stearic acid, and just divided the number of saturated FAs in half – not exactly inspiring confidence, or is it? And then everyone just fills their databases with blindly copied numbers from someone else, without checking. Umm… a good opportunity to not only copy errors, but also introduce new ones.

Fair enough, shuffling a few % of S to P is not a difficult task to correct the recipe, BUT this is a job that I should not have to do by myself, each time.
 
To which oil are you referring?

Oils do indeed vary in fa profile by season, climate, and genotype. Cotton may not vary much by breeding but other genus certainly do... Sunflower for example.

The searchable database at SOFA will illustrate these and more
SOFA (Seed Oil Fatty Acids, http://sofa.mri.bund.de/)

The list of different results for Prunus alone is staggering.

As to what that means *functionally* for soapmaking, find a calculator that works for you and stick with it as it should be internally consistent.

Or learn to hand calculate the sap's from the analysis for the oils you use... and do it for each new oil.

I recommend learning to hand calculate, even if you never do again, you'll know how.

And I recommend as well realizing that plant and animal oils do vary, which is why SAP values are given as ranges, and soap comes out fine even with variation.

You're not building a heavy water reactor. You can't force the details to be rigidly repeatable.
 
52.5 - 17.2 - 23.9 - 2.5 https://www.cotton.org/journal/2010-14/2/upload/JCS14-64.pdf

Particularly that last article is an awesome resource that discusses in great length how little can be changed in the fatty acid profile by breeding and growth climate.
i do not believe that this paper can be reliably used to conclude "little can be changed ... by breeding and growth climate"

they limited the varietal choices to "commercially acceptable cotton genotypes"
and stated "Although the results indicate that breeding cotton for modified oil composition should be feasible, the range of variation observed within the genotypes studied was insufficient to provide useful traits for breeding."

but ... thank you VERY much for pointing me in the direction of the article!
i now have a theory on why my chicken have gone off the lay a little (Cyclopropenoid Fatty Acid content in Mallow plants)
easy to test - i have some weeding to do ;)

edited to add
dear owl
you might find it surprisingly enjoyable to create your own calculator
🥰
 
Last edited:
To which oil are you referring?
To cottonseed oil in particular. I know now that I have to hand-calculate it, since no existing calculator bothers to use numbers that are anywhere close to the real values. And with “anywhere close” I mean that neither of the calculators comes closer than 11σ (palmitic) or 73σ (stearic) to the average of reported literature values. That's not some random fluctuation. That's a significance level for which you would get a Nobel prize in particle physics.

I'm totally aware that this particular case plays no practical role, since the most important part in soap calculations is getting saponification value/lye balance right, and on top of this the similarity of P and S hides imprecisions. I'm just unsettled of the observation that the aura of infallability of soap calculators is crumbling. For hand calculations I need numbers, and where do I get the numbers from? It was private curiosity that I did some research into cottonseed oil, and only then I found out that the soapcalc numbers aren't sound. Nobody tells me for which ingredients I better should do an in-depth scientific journal research session next.

The searchable database at SOFA will illustrate these and more
SOFA (Seed Oil Fatty Acids, http://sofa.mri.bund.de/)
That sounds like an exciting resource, but it isn't accessible at the moment, and archive.org to no avail :(
 
Care to share? I don't have the energy to read a long scientific article tonight, but egg production has been shocking lately...
from owls cottonseed article "Cottonseed oil also contains modest levels of cyclopropenoid fatty acids, which are considered anti-nutritional."
the mallow family contains Cyclopropenoid fatty acids
the anti-nutritional issue (after a quick look) is with reproduction

tl;dr
i wanted to know what Cyclopropenoid fatty acids were and why they were consider anti-nutritional

I looked around and found that cottonseed is bred to contain less of these
and that the main issues are with reproduction (in cows, people, sheep, poultry etc)

another article gave a list of plant families that contain cyclopropenoid fatty acids
the mallow family contains Cyclopropenoid fatty acids

i found an egg board article, but closed it before i saw your question (keyphrase white/pink egg)

CPEFA might be useful to lower rat/mice populations on farms but that is totally OT ;)

a link
Foods magazine in 2020 www.mdpi.com/2304-8158/9/7/901/pdf
"There is a substantial interest in CPEFA determination due to the physiological effects that they may produce in animals and humans [1,2,6]. Seed lipids naturally containing cyclic fatty acids are extensively consumed, especially in tropical areas [2,3]. Sterculic, malvalic, and dihydrosterculic acids are present in cottonseeds, particularly those of Gossypium hirsutum (0.5–1% of total fat) [7]. Cottonseeds, cottonseed oil, and cottonseed meal are commonly included in the diet of dairy ruminants, notably in cotton-producing areas of the Southeast Asia countries (including China), Brazil, and USA [8]. CPEFA have been linked to potential constraints of cottonseed-based diet because of their possible deleterious effects on animal performance and animal health (reproductive disorders, growth retardation and altered lipid metabolism), not only in ruminants but also in other animal species, including rainbow trout, rodents, and poultry"
 
For hand calculations I need numbers, and where do I get the numbers from? It was private curiosity that I did some research into cottonseed oil, and only then I found out that the soapcalc numbers aren't sound. Nobody tells me for which ingredients I better should do an in-depth scientific journal research session next.
numbers for the common commercial fatty acids should be the most reliable
 
Last edited:
To cottonseed oil in particular. I know now that I have to hand-calculate it, since no existing calculator bothers to use numbers that are anywhere close to the real values. And with “anywhere close” I mean that neither of the calculators comes closer than 11σ (palmitic) or 73σ (stearic) to the average of reported literature values. That's not some random fluctuation. That's a significance level for which you would get a Nobel prize in particle physics.

I'm totally aware that this particular case plays no practical role, since the most important part in soap calculations is getting saponification value/lye balance right, and on top of this the similarity of P and S hides imprecisions. I'm just unsettled of the observation that the aura of infallability of soap calculators is crumbling. For hand calculations I need numbers, and where do I get the numbers from? It was private curiosity that I did some research into cottonseed oil, and only then I found out that the soapcalc numbers aren't sound. Nobody tells me for which ingredients I better should do an in-depth scientific journal research session next.


That sounds like an exciting resource, but it isn't accessible at the moment, and archive.org to no avail :(
Hmmm it was there last time I looked, last spring.

Try this, it uses their data
PlantFAdb: Gossypium hirsutum - Upland Cotton
https://plantfadb.org/plants/10683
I couldn't remember more than Genus for cotton, picked one... but you can search for thousands of plants at the main search page here:

https://plantfadb.org/plants
 
More soap calculator quirks :eek:

1630369576606.png


11+8+33+50=
102

By now I'm used to FA profiles of the usual suspects (coconut, mustard, cupuaçu…) don't quite add up to unity. But here it's above 100%???
(SoapCalc and Soapee have the same numbers)

If you ever wanted your soap to surpass expectations just by the few % that make all of a difference, place your bet on pumpkin seed oil! 😂
 

Attachments

  • 1630369326269.png
    1630369326269.png
    34.4 KB · Views: 8
Maybe. It's just barely possible to get close to 100 if all the values are generously rounded up by 0.5.

Another possibility is that whoever compiled the FA database in the first place, took numbers from different sources. And/or unreliable numbers with systematic error. Unfortunately we will never know, since soap calculaotrs are so reluctant to delegate responsibility (acknowledge sources, good scientific practice) :(.
 
curiously the saturated to unsaturated does add up to 100
(19:81, so the "error" is in either oleic acid or linoleic acid)
 
AND just to throw a monkey into the works, not all Fatty Acids are even listed in the first place. What about the trace ones? I don't think any calculator is going to be 100% accurate for any given oil 100% of the time, because the profile for a given oil can change with each crop.

We keep getting reminded that these numbers are GUIDELINES not absolutes.
 
Botanic and seasonal variability is indeed a thing, but I'm having a hard time to accept this as an excuse to miss ALL FAs (particularly those for which the ingredient is unique for; FWIW, myristic acid is not a minor FA) and make up fantasy values for others (???).

Btw, all calculators, tables, and vendors agree with the saponification value of Ucuúba butter, so it's not just a shifted line while manually transferring numbers from a table. (What then? I'd like to know, if only for my own reassurance that I don't have to worry to recommend soap calculators.)

To achieve that tabulated SAP of 0.146, the missing 20% balance in the SoapCalc/SMFriend profile would have to be comprised of unsaponifiables + minor fatty acids only, and have a SAP close to coconut oil. That would make Ucuúba either a fabulous source of exotic phytochemicals or a better MCT source than coconut/palm kernel.
 
It wonder if the various calculators copied from similar sources (databases or books) and filled in what wasn't covered from the sources they found independently. I mean if it's hard for us hobbyists I wonder how much info there actually is out there to draw from. It's kind of a simple process to find SAP values with basic chemistry and a bit of math, kind of unfortunate that it's probably far more difficult to derive individual FAs from oils. Regardless, this topic is interesting as hell and worth an examination. I hope there are soap calc builders here online taking notes. A ripe opportunity to separate from the masses and provide accurate and up to date data, hell I know that would be worth paying for.
 
I was wondering about coconut 92 deg (fully hydrogenated). The calcs are not adding the extra stearic acid that will come with hydrogenation of coconut oil. Coconut 92 deg should have:

Stearic: 13
Oleic: 0
Linoleic: 0

But the calcs still show the same FA composition as coconut 76 deg:

Stearic: 3
Oleic: 8
Linoleic: 2

In SMF I have added my own coconut 92 deg with the correct FA composition.
 
I was wondering about coconut 92 deg (fully hydrogenated). The calcs are not adding the extra stearic acid that will come with hydrogenation of coconut oil. Coconut 92 deg should have:

Stearic: 13
Oleic: 0
Linoleic: 0

But the calcs still show the same FA composition as coconut 76 deg:

Stearic: 3
Oleic: 8
Linoleic: 2

In SMF I have added my own coconut 92 deg with the correct FA composition.

I've just ran both through on soap calc and they have the same exact FA numbers for both 92 and 76. Was not even aware there was a difference otherwise. Ok, now I'm totally with RO and getting a little pissed about this, as I had not known there was a pretty large difference between CO-based specifically on the calc numbers. I understand that these tools are free and designed for convenience, but there is an aura of authority when claiming specific values for specific fats. Perhaps there was a mistake in tabulation, however I've learned a valuable lesson here, as the old precious metals forums used to say: DYODD (do your own due diligence).
 
Back
Top