# What does SF mean in a recipe?



## misfities (Apr 5, 2015)

This is probably obvious, but I am new. I found some soaps that interest me and the lady lists her ingredients online. She abbreviates everything. I get that FO is fragrance oil and EO is essential oil. What is SF though? If she's using castor oil as part of the recipe, why not list it under ingredients with the other oils? I emailed her a while ago, but no response. 

http://anitaslalaland.blogspot.com/2011/06/021-canola-sunflower-soap.html#comment-form

Ingredients:
15% Olive Oil、30% Canola Oil、20% Sunflower Seed Oil、20% Coconut Oil、15% Palm Oil

SF : Castor Oil、Wheat Germ Oil
FO : Jasmine
Additives: Menthol Crystal


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## cmzaha (Apr 5, 2015)

Looks like she is superfatting with castor and Wheat Germ Oil. If making cold process soap it makes no difference what you superfat with because lye will take what it wants. Plus Castor is a weird oil, in my opinion to superfat with. It is thick and sticky and is really used to support lather in soap. With Hot Process you can add in super fat oils after the gel stage without the risk of the lye using up all the super fat oils.


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## Dorymae (Apr 5, 2015)

SF means superfat. When making HP soap you can add oils after the cook. These oils will not react with lye to make soap (the reaction is done) and stay as oil in the soap. She separated them out so you would know which oils are still oils and not oil turned to soap.


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## KristaY (Apr 5, 2015)

Sorry misfities, but I haven't heard that and couldn't find it on the "acronym and abbreviation" sticky. SF is super fat, but can't find FS. Is it a typo, maybe?

But, jeez. When I first read through your thread, I read the last line as Crystal Meth. You can tell where my work leads at times, huh? :crazy:


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## Obsidian (Apr 5, 2015)

You mean SF? that means superfat, if you make HP, you can choose which oils you want for SF so some people list it separately. If you are making CP,  all the oils go into the pot together.

Personally, I would never use castor for SF in HP, it needs to be saponified in order to help make big bubbly lather. Seeing that she doesn't list how much castor, I would lower the canola by 5% and replace it with castor. I wouldn't use the wheat germ.

Actually, I wouldn't make that recipe, its heavy on canola which could lead to DOS. I suggest keeping canola at 15% or less. I'm not crazy about sunflower oil either but plenty of other people are. If you can find it, high oleic sunflower is better to use.

You might check out some of the recipes here, just make sure to resize them as most are pretty large batches and being a new soaper, you should stick to 2 lb batches.
http://www.millersoap.com/


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## not_ally (Apr 5, 2015)

You all are such great advisors.  I have been thinking of making my first batch of HP, goodness knows what would happen without you.  I did not know that (among the myriad things) about castor as a SF choice in HP.  Misfities, we are lucky.


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## misfities (Apr 5, 2015)

I get it now. Seems so obvious. Since I only do cold process, I don't know much about superfatting. So it means she adds castor and wheat germ as 5% of her oils as a safeguard to cover the lye amount?


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## Dorymae (Apr 6, 2015)

misfities said:


> I get it now. Seems so obvious. Since I only do cold process, I don't know much about superfatting. So it means she adds castor and wheat germ as 5% of her oils as a safeguard to cover the lye amount?



Not really, the soap is already cooked and zap free so it is used for the skin benefits more than for a safeguard.


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## The Efficacious Gentleman (Apr 6, 2015)

You currently do superfat in cp. It is often also called a lye discount - you use 5% less lye than is required, so 5% of your oils remain as oils, not soap. 

In cp, it will be pretty much a split of all your oils based on their ratios. So if you make a cp soap with 50% lard, 30% oo and 20% co, your 5% superfat will be made up of a similar ratio of those oils. 

In hp, you can finish the saponification of a soap with 0% lye discount and then add in an oil or oils - none of it will saponify as the lye is already gone. 

As for this one here, she only lists a recipe. Looking at the image I can't tell if it is hp or cp though.


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## McSpin (Apr 9, 2015)

The Efficacious Gentleman said:


> In cp, it will be pretty much a split of all your oils based on their ratios. So if you make a cp soap with 50% lard, 30% oo and 20% co, your 5% superfat will be made up of a similar ratio of those oils.



From things I've read, I was under the impression that different fats did not saponify at the same rate, so ratios would change with the slowest saponifying oils left at the end.  So, you're saying the different fats saponify at the same rate, which would have to happen for the ratios to remain the same?


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## The Efficacious Gentleman (Apr 9, 2015)

McSpin said:


> From things I've read, I was under the impression that different fats did not saponify at the same rate, so ratios would change with the slowest saponifying oils left at the end. So, you're saying the different fats saponify at the same rate, which would have to happen for the ratios to remain the same?


 

Which is why I said "Pretty much" not "totally 100%" - different oils do indeed saponify at different rates, but with the oils and lye well mixed throughout will mean that, while it won't be 100% the same it won't be too far off.


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## McSpin (Apr 9, 2015)

Some fats go to trace at a rate that seems much faster to me, than other fats. For instance, a lot of the solids oils seem to trace in less than a minute, while some of the liquid oils (like olive) seem to not trace for many minutes of stick blending.  Isn't this a sign that some are saponifying much faster? And if so, doesn't it mean that they would be saponified completely before the ones slower to trace?


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## Susie (Apr 9, 2015)

Trace is the _beginning_ of saponification, not the end.  Saponification takes 24-48 hours to complete.  This means that the lye is going to continue to change all oils until it is used up.  There is simply no possible way to tell the lye to leave this oil or that one alone until last.


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## McSpin (Apr 9, 2015)

Susie said:


> Trace is the _beginning_ of saponification, not the end.  Saponification takes 24-48 hours to complete.  This means that the lye is going to continue to change all oils until it is used up.  There is simply no possible way to tell the lye to leave this oil or that one alone until last.



Of course, you can't tell it anything.  But if it is saponifying one faster, how will you stop it from completely saponifying that one first?


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## Susie (Apr 9, 2015)

If you make a soap with 5% "superfat"(AKA lye discount), that lye is going to convert all but 5%(ish) of the oils into soap.  Period.  Kevin Dunn has done studies on whether you can choose certain oils to be a "superfat" in a soap or not.  You can't.

You also can't judge on how fast an oil saponifies by the speed at which it comes to trace.  You can make a more educated guess, but not know for sure.


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## McSpin (Apr 9, 2015)

I probably just don't understand saponification and how it works. I tried to research this before bringing this up, but I can't find anything on the web that discussed the chemistry, explaining how the different fatty acids are saponified at approximately the same rate, with the explanation.

As an example, stearic acid increases saponifcation drastically.  I thought that meant that the stearic acid is saponified first.  You seem to be saying that it isn't and that they are all saponified at approximately the same rate.  If so, how is the stearic acid increasing the rate, without being the specific fatty acid that is being acted upon?


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## coffeetime (Apr 9, 2015)

DeeAnna actually explained the saponification chemistry on a different thread a couple of months ago, I think. Perhaps if she comes by, she can link to it.


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## The Efficacious Gentleman (Apr 10, 2015)

Coffeetime, that was a great way of wording it. I'm on the app but I'll see if I can find it when I'm at a computer. 

Mcspin, the lye can bond with certain oils more readily, but it's not hard-and-fast set in stone as if the lye binds with all of the stearic before it even starts to bind with the olive oil. DeeAnna's post was great, so I'll let that do the talking when it is found


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## The Efficacious Gentleman (Apr 10, 2015)

I typed "lye party site:soapmakingforum.com" in to Google and it was the top result 

http://www.soapmakingforum.com/showpost.php?p=492578&postcount=12

"
Yes, the rate of saponification does vary with the type of fat, and yes the saturated fats tend to saponify easier than the unsaturated fats. But even if you knew the reaction rate for each fat precisely, you still would not be able to accurately predict the specific fats left over after saponification is done. The superfat composition will depend on the amount of each fat used, the method of saponification, the temperature of the soap batter, etc.

It's like the fats and lye are having a big party with more fats (girls) than lye (guys) in the house. The guys at the party (the lye molecules) prefer blondes (coconut oil), but there are lots of pretty brunettes and redheads on the dance floor to mix with. These darker haired girls (olive oil, for example) dilute the concentration of blonds. This means the lye guys will find it harder to pair up with a girl with the "right" hair color and easier to pair up with a girl of another hair color (olive oil reacting with lye rather than coconut oil reacting w lye). 

Even though some of the lye guys are eventually going to pair up with the blonds they prefer, many will pair up with the brunettes and redheads instead. At the end of the party, the lye guys will have hooked up with a fair number of the darker haired gals by the end of the party. It is likely that at least some girls of each hair color will remain without a partner. Given that this interaction is all about chemistry and probability, it's difficult to predict how many blonds, brunettes, and redheads will be left over.

There's just no way one could create a simple table to answer this question. HP is absolutely the way you should go if you want rigid control of the superfat composition. "


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## Susie (Apr 10, 2015)

Thank you, Craig.  I remembered the thread, and hunted, but I forgot about the lye party.  Any possibility we could get that one stickied?  We seem to have had a bunch of folks to explain the superfat issue to lately, and it sure would be convenient to point to a sticky.


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## McSpin (Apr 10, 2015)

That analogy is not hard to follow, but it doesn't explain the chemistry that I was hoping to find.  I've always been a person who like to know why.  That does not explain why or how it happens - just that it does.  

How did someone initially determine this?  I can understand that the lye doesn't use all of the stearic acid before it acts upon another fatty acid, but if the rate of reaction differs, then it should convert the stearic acid faster, leaving a different ratio at the end of saponification compared to the start.  I'm curious what that ratio is and how it is determined.  By the sounds of it, someone has figured this out, but I'm not finding the detail anywhere.


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## Susie (Apr 10, 2015)

OK, then you probably need to go to the source for info:

http://www.amazon.com/dp/1935652095/?tag=skimlinks_replacement-20

If it is not the right book, it will be in one of his books.  Or you can go get a membership in fyi101.com:

http://fyi101.com/superfatting-and-lye-discounting-part-i-presented-by-dr-kevin-dunn/


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## McSpin (Apr 10, 2015)

The book looks like it would be a good one to have even if it doesn't give the answers I'm looking for.


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## topofmurrayhill (Apr 11, 2015)

The Efficacious Gentleman said:


> In cp, it will be pretty much a split of all your oils based on their ratios. So if you make a cp soap with 50% lard, 30% oo and 20% co, your 5% superfat will be made up of a similar ratio of those oils.



I must respectfully disagree. The lye does not see oils; it sees fatty acids. It will preferentially react with free fatty acids and more saturated fatty acids. Whatever oil remains in the soap is unlikely to resemble any oil that was in your recipe.

Thus even if you make a one-oil soap with a generous lye discount, I don't believe it is valid to say that the soap is superfatted with that oil.

One might say that in cold-process soapmaking, the original oils used in the formulation, whether one or many, are essentially destroyed.


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## not_ally (Apr 11, 2015)

**** it, why do guys always prefer blondes!  In soap as in life, apparently   EG, if you make another analogy about all the tall girls being taken up first, I may have to use a frowny face emoticon!


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## The Efficacious Gentleman (Apr 12, 2015)

topofmurrayhill said:


> I must respectfully disagree. The lye does not see oils; it sees fatty acids. It will preferentially react with free fatty acids and more saturated fatty acids. Whatever oil remains in the soap is unlikely to resemble any oil that was in your recipe.
> 
> 
> 
> ...




The fatty acids that we use for soaping are commonly referred to as oils. They are fatty acids, of course, in many cases they are also triglycerides, but they are very often oils. To use that term is not correct, in sure you'd agree. Unless you think that a fatty acid used in soaping is NEVER also known as an oil?

I also disagree with your disagreement. It would be wrong to say that, if I make a single oil soap (let's say a Castile) and have a 0% lye discount that my soap has olive oil - it doesn't, it has sodium or potassium olivate. 

If I had a 5% lye discount, that means that 5% of the olive oil did not react with lye - the triglyceride is still intact, the olive oil has not changed in any way - it is still olive oil. Lye creates soap by breaking the fatty acid down and joining with the parts that are left. So there is not enough lye in a lye discounted soap to do that, so there must be oil left as oil (or fatty acids left as fatty acids, if you really must)


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## topofmurrayhill (Apr 12, 2015)

The Efficacious Gentleman said:


> If I had a 5% lye discount, that means that 5% of the olive oil did not react with lye - the triglyceride is still intact, the olive oil has not changed in any way - it is still olive oil. Lye creates soap by breaking the fatty acid down and joining with the parts that are left. So there is not enough lye in a lye discounted soap to do that, so there must be oil left as oil (or fatty acids left as fatty acids, if you really must)



Your olive oil is a collection of fatty acids in the form of triglycerides. Those fatty acids are present in proportions that are characteristic of olive oil. Introduce lye and the fatty acids react with the caustic at different rates. Once the process is complete, virtually all of the saturated fatty acids (palmitic, stearic) will have become soap. We began with a large amount of monounsaturated oleic acid, and certainly some of that will be left over. We began with a modest amount of linoleic acid, but it saponifies very slowly, so I imagine some of that will be left over too, if not most of it.

As you see, the caustic has cherry-picked it's favorite fatty acids and turned them into soap, and left behind the ones it doesn't like as much. The proportions remaining as oil have changed, and many of the triglycerides have been broken up. If you could extract all the material left over from the original olive oil, it would not resemble olive oil in composition or properties at all.


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## The Efficacious Gentleman (Apr 12, 2015)

That is interesting - can you link to the study with the numbers on that?  I also think McSpin would enjoy that

ETA - I ask, because it would be interesting to see how the whole probability question is answered:  a certain fatty acid saponifies more easily, but does that always mean that, if 1 molecule is more easily saponified is also 'competing' with 4 others that are slower, does the first ALWAYS go first, or does probability come in to play?


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## topofmurrayhill (Apr 12, 2015)

The Efficacious Gentleman said:


> That is interesting - can you link to the study with the numbers on that? I also think McSpin would enjoy that
> 
> ETA - I ask, because it would be interesting to see how the whole probability question is answered: a certain fatty acid saponifies more easily, but does that always mean that, if 1 molecule is more easily saponified is also 'competing' with 4 others that are slower, does the first ALWAYS go first, or does probability come in to play?


 
I'm sure that you're correct in thinking of it in terms of probabilities. They wouldn't saponify in order. They would saponify simultaneously, but at different rates until the caustic runs out. Those rates vary significantly though. You see how much faster the reaction goes with coconut oil (lauric, myristic) or palm oil (palmitic) or butters (stearic) or heaven forbid free stearic acid. Blammo. I would think those saturated fatty acids would get more or less completely gobbled up in most cases.

Think about how much more laid back it is making castile soap. Should be plenty of opportunity for the palmitic (and some stearic) in the olive oil to react while the lye is chewing on the oleic.

I don't know of numbers regarding the dynamics of this. I'm speaking in terms of basic principles and simpler experiments, which I believe are on your bookshelf. I don't have it handy, but I was the primary proofreader for Scientific Soapmaking. I've gone through it page by page, sentence by sentence, checked every calculation, did every problem. Relevant parts would include the chapter on superfatting, the stuff about single-oil soaps, and more.


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## The Efficacious Gentleman (Apr 12, 2015)

Interesting idea, but does the rate of saponification have such a bearing on the finished result?  So if we are talking about how long it takes from the start of the process to the end of the process, that has little impact if there is no real difference in how quickly the raw lye molecules start to bind with the fatty acids.

To use the analogy of the party, while it make take a long time to talk a brunette in to letting you walk her home and steal a kiss on the cheek on the door step compared to how long it takes to talk the blonde in to the same thing, if within 5 minutes of the party starting people are already paired up and the chaps are sweet talking the ladies, the mix of the girls left alone won't be dependent on how long the sweet talking takes as once it is started, that particular couple are paired up.  

It's not like a chap starts talking to a brunette, get's bored and finds a blonde - once the lye has started to bind with an acid, it won't then stop and find another acid that is easier, will it?

Edited to add, unless the rate also indicates how easy it is for the process to actually start in the first place


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## topofmurrayhill (Apr 12, 2015)

The Efficacious Gentleman said:


> It's not like a chap starts talking to a brunette, get's bored and finds a blonde - once the lye has started to bind with an acid, it won't then stop and find another acid that is easier, will it?



Well I reckon that is a very good question. I remember reading -- I think in some industry material I turned up -- that exactly such a thing happens as an ongoing process after the soap is produced. So the residual oil in the soap could continue to change due to the wanderings of promiscuous sodium ions. I'll let you know if I can figure out where that was.

However, I don't think that process is necessary to transform the residual oil in our soap. Even if the saponification proceeds quickly, unsaturated fatty acids are big contributors to that speed. At the other end of the spectrum, polyunsaturated fatty acids are feeling like relative wallflowers. Read about the linoleic single-oil soap in Dunn's book and how recalcitrant it was about being soap.

One interesting issue you've brought up with the matter of bored wandering lye is to what extent even the superfat oil in HP soap could change over time. I couldn't say for sure, but as crafters there is still much we might learn.



The Efficacious Gentleman said:


> Edited to add, unless the rate also indicates how easy it is for the process to actually start in the first place



Yes, I think something like this might be the way to think about it. Or maybe whether the guys are preferentially attracted to certain girls. In deference to not_ally, I would suggest the brunettes are more in demand.


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## Susie (Apr 12, 2015)

Having just spent an hour on another forum, I have to tell y'all how wonderful it is to read people disagreeing, but having a good discussion that helps everyone learn more about soapmaking, and it not degenerate into _ad hominem_ attacks and name calling!


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## The Efficacious Gentleman (Apr 12, 2015)

I think it is because most people here are willing and eager to learn.


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## McSpin (Apr 21, 2015)

TEF posted this link in another thread:
http://cavemanchemistry.com/LyeDiscount-Dunn.pdf

It seems to verify that the fatty acid profile of the superfat is not the same as the initial oils used - at least for the 3-4 combos that were tested in this article.    It seems to support topofmurrayhill's theory.


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## The Efficacious Gentleman (Apr 21, 2015)

McSpin said:


> TEF posted this link in another thread:
> http://cavemanchemistry.com/LyeDiscount-Dunn.pdf
> 
> It seems to verify that the fatty acid profile of the superfat is not the same as the initial oils used - at least for the 3-4 combos that were tested in this article.    It seems to support topofmurrayhill's theory.



There is also another thread discussing a similar topic, the idea that fatty acids (non triglycerides) can "easily" swap around, but it raised the question of whether or not triglycerides can be affected in the same way due to the strength of the reaction required, plus how much time is required.  Might be interesting read for you.


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## McSpin (Apr 21, 2015)

I saw that, but like you mentioned in that thread, time was a factor they didn't discuss and it really is important to know that in order to understand the meaning a bit better.


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## tbeck3579 (Apr 23, 2015)

*What Party? Where? Who?*

This is such an intelligent group of people assembled here!  Very refreshing!  

I  joined this wonderful forum today in search of the "perfect" soap  recipe -- perfect for my skin type and personal hygiene preferences.   I've been dabbling in soap making for many years; always CP, but HP is  looking a bit more appealing.  After reading this thread I'm thinking CP  soap may not be the ideal soap for me.  Thank you so much for this  debate!  It helped me to think through the science of soap making and  helped me with my quest.  You folks are the best!

As I was reading this thread I couldn't help but think there must be  MANY variables in making soap.  Just a quick  search and that hunch seems to be correct.  This study, for example: -- Variations in the  temperature and in the composition of the medium alter the proportions  of individual                      fatty acids. So not only being blond, but possible ethnicity (German or Norwegian) in a room that is warm from too many party goers can influence the outcome.  There is so much to consider when "cooking"  that perfect bar of soap


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## McSpin (Apr 24, 2015)

tbeck3579 said:


> This study, for example: -- Variations in the  temperature and in the composition of the medium alter the proportions  of individual fatty acids.



Let me see if I understand what you quoted.  Is the study saying that the fatty acids saponify in a different ratio at different temperatures?


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## tbeck3579 (Apr 24, 2015)

McSpin,

The study states that temperature changes proportions of fatty acids, as does the medium - following that through to a logical conclusion means it will change saponification because saponification relies on the availability of fatty acids.  I should say my view of this is, environmental conditions (medium and temp) will change the outcome because the fatty acids have changed.  I was thinking in terms of the huge variations in the oils used in soap recipes, and even the slight differences in the temperatures when "cooking" it.  However, even the genetics of different olive trees would have some impact -- in my mind anyway.  Logical, but I hadn't given it that much thought before this discussion.  A change in temp and/or medium will change most things, either minutely or drastically.  It doesn't take an advanced science degree to validate the hypothesis, but he has one, and did.  I love science because scientists are always trying to prove "it ain't so"   Well, I should say I love science that isn't bought and paid for in an effort to sell something to someone.  Mark Twain hit the nail on the head when he said, "lies, **** lies, and statistics."

Take care,
Teresa


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## DeeAnna (Apr 25, 2015)

^^^^ Yes.


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## topofmurrayhill (Apr 25, 2015)

tbeck3579 said:


> I should say my view of this is, environmental conditions (medium and temp) will change the outcome because the fatty acids have changed.  I was thinking in terms of the huge variations in the oils used in soap recipes, and even the slight differences in the temperatures when "cooking" it.  However, even the genetics of different olive trees would have some impact -- in my mind anyway.



This shows the fatty acid variation in mid-oleic sunflower oil based on location (soil and weather). The seed in question is specially bred to have less linoleic and more oleic fatty acids in its oil. There are three different types of sunflower oil on the market that produce distinctly different results in soap. Plus, as you can see, each of those has its own variations depending on growing conditions.


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## tbeck3579 (Apr 27, 2015)

topofmurrayhill said:


> This shows the fatty acid variation in mid-oleic sunflower oil based on location (soil and weather). The seed in question is specially bred to have less linoleic and more oleic fatty acids in its oil. There are three different types of sunflower oil on the market that produce distinctly different results in soap. Plus, as you can see, each of those has its own variations depending on growing conditions.




I'm not sure what study you are referring to.  I did a quick search but I couldn't find the study quoted, but it wasn't specific to oils, it was specific to varying proportions of fatty acids.  I'm not going to spend a great deal of time searching again because it seemed logical, and I've moved on to the next step in my personal soap making quest.  I have the information I need to help me formulate a soap for my personal needs.  It's good information (to me anyway) and anyone can use it or not, all info is FWIW to you personally   This is the internet and gleaning what I need to answer my questions is what's important to me.  Everyone agreeing with someone elses research, not so much   Now if it was my personal hypothesis, and my experiment, I would be willing to defend it, hahaha


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## topofmurrayhill (Apr 27, 2015)

tbeck3579 said:


> I'm not sure what study you are referring to.  I did a quick search but I couldn't find the study quoted, but it wasn't specific to oils, it was specific to varying proportions of fatty acids.  I'm not going to spend a great deal of time searching again because it seemed logical, and I've moved on to the next step in my personal soap making quest.  I have the information I need to help me formulate a soap for my personal needs.  It's good information (to me anyway) and anyone can use it or not, all info is FWIW to you personally   This is the internet and gleaning what I need to answer my questions is what's important to me.  Everyone agreeing with someone elses research, not so much   Now if it was my personal hypothesis, and my experiment, I would be willing to defend it, hahaha



Sorry there was supposed to be an attachment, included herein. Some of the points in question reminded me of this, which I think is the only time I've seen specific fatty acid variations shown for various planting locations. Same genome, different environments.


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## topofmurrayhill (Apr 27, 2015)

Via the mobile interface, a link will suffice. 

https://www.sunflowernsa.com/uploads/resources/51/warner_.pdf


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## tbeck3579 (Apr 28, 2015)

topofmurrayhill said:


> Via the mobile interface, a link will suffice.
> 
> https://www.sunflowernsa.com/uploads/resources/51/warner_.pdf



Genetics of any plant come into play at every stage of the game -- as does the soil, weather, and growing conditions.  Everything from the seed you choose, germination, soil, which pests and diseases are present at any given time of the year, and when/how you harvest your crop will impact the outcome.  As I've said many times, a dumb farmer is a dead farmer.  

I live in ag country, surrounded by nothing but soybeans and corn.  I literally do not have a stop light for more than 20 miles, and stop signs are mere suggestions -- BTW, take the suggestion when the corn is tall   I am completely against GMO's and the dog gone GM corn is growing all around me (thank you corporate America!).  The fields are pretty, no weeds, and the farmers are proud of their weed free crops.  Round-up is already being applied to the fields. Tt's a subject that I try to steer clear of because it gets my cackles up.  I know that feeding the world is no simple matter, but GMO's really aren't helping to solve a very real problem, IMHO. Genetics are extremely important and influence the outcome.


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## topofmurrayhill (May 1, 2015)

The Efficacious Gentleman said:


> That is interesting - can you link to the study with the numbers on that?  I also think McSpin would enjoy that
> 
> ETA - I ask, because it would be interesting to see how the whole probability question is answered:  a certain fatty acid saponifies more easily, but does that always mean that, if 1 molecule is more easily saponified is also 'competing' with 4 others that are slower, does the first ALWAYS go first, or does probability come in to play?



Some specifics you were interested in are in here. When analyzing lye-discounted soap, it was found that the slower-saponifying fatty acids predominated. The composition of the residual fat was not similar to the original oils.

http://cavemanchemistry.com/LyeDiscount-Dunn.pdf


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## DeeAnna (May 4, 2015)

Dunn investigated three blends -- coconut oil + castor oil, palm + grapeseed oil, and palm + olive oil. He used 10% superfat/lye discount, and added the "superfat" (sorry, Effy) in two ways -- in the starting blend of fats and at trace. 

In two of the three fat blends, he found the unsaponified fat remaining in the finished soap contained more unsaturated fatty acid than was in the original blend of fats used to make each soap. With the unsaturated ricinoleic acid (from castor oil), the opposite was true -- less ricinoleic acid was in the superfat than was present in the original fat blend. These trends were always true regardless of when the superfat was added -- either up front or at trace.

For the tests looking at linoleic acid (from grapeseed) and oleic acid (from olive), the superfat contained 2 to 3 times more unsaturated fatty acid than the original fat blend. That's a definite increase, but it is also true that saturated fatty acids remained the main fatty acids in the superfat -- very roughly 80%. For the test looking at ricinoleic acid (from castor), the superfat contained about half the ricinoleic acid compared with the original fat blend.

Dunn did not investigate more complex fat blends, due to his need to identify from which fat the fatty acids came from. If you repeated his experiments but looked at a blend that contains, say, avocado and olive, you could certainly measure the amount of oleic acid in the original fat blend and in the superfat. But from which fat does the oleic acid come from -- the olive or the avocado? There is no way to tell without doing something like isotope marker studies.

Even though we don't know how the fatty acid content will change when a complex blend of fats is used, I'd say it's reasonably safe to guess that oleic, linoleic and linolenic acids may be higher and ricinoleic acid might be lower in the superfat ... but honestly, here's no way to predict exactly how much without actually studying each mixture and looking for trends. I'd bet strongly that temperature, mixing intensity, water content, and a number of other variables will affect the outcome as much as the fats.


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