rancid/old olive oil on soaps...

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hlecter

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Hi all!

I have a ton of old pure olive oil which gone a little bit rancid by time. Its production date was 2-3 years ago... I am not gonna use it on food...

If i use that oil on CP for castiles and bastiles is it sure that my soaps are going to develop DOS or other oxidizing problems?

I ve read on craftblogs and discussions that it can be used on soapmaking. Also could i minimize the chance of such annoying issues by superfatting at 4%?

Sorry for those perhaps stupid questions :mrgreen:
 

Susie

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Not stupid questions at all.

I would not use the oil. I can almost guarantee your soap will develop DOS, which is, after all, rancidity.
 

lsg

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If it smells rancid, I would not use it, either.
 

shunt2011

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Nope, I wouldn't use it either. You would likely just have to throw it away anyway.
 

cmzaha

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Does it smell rancid and has it had the seal broken? If the seal is not broken it is probably just fine. I have 4 different oils here that are most likely at least 10 yrs old. They came from a gal that was destashing and after driving 5 hrs to pick up her supplies, did not tell me these were old bottles of oil. Sesame, Cherry Kernel, Peach Kernel, Castor and forget the other one. The seals were not broken and the oils are just fine. These were in the yellow bottles from Soapers Choice. When I started soaping 7 yrs ago the bottles were yellow. Not one soap has acquired dos and they are several months old, but I do add BHT to all batches of soap. So as long as they still have the inside seal and not exposed to air they should be fine. I would go for it, age them and see what happens. But that is me....
 

lionprincess00

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^^^
I personally would agree with Carolyn. Also she and I superfat pretty low, I personally use 2% sf regularly. If the seals aren't broken, they do not smell rancid, you could consider a lower sf (lower than your 4% you mentioned) if you are still comcerned.
 

navigator9

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You say it's gone rancid by time. Does that mean that you think it's rancid because of date, or have you actually smelled it? If you smell it, and it smells rancid, I would not use it. If it smells OK, I'd use it to make soap for my own use, but personally, I wouldn't sell it. I'd also just make a small batch to start with, to see if it develops DOS. If it does, no sense in wasting more ingredients to make bars that will develop DOS anyway.
 

dixiedragon

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I using rancid oils at 5% in my recipes. So far, no problem. I did have one batch that developed a lot of something DOS like, but I think that was contaminates of some kind. Batches before and after had no problems.
 

DeeAnna

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Also, if you smell the oil, be sure to pour a little of the oil in a little bowl and smell that. Sometimes a bit of oil on the spout or cap turns rancid when the bulk oil inside the container is fine.

***

Hand crafted soapmakers nowadays have the option of using fats that are fresh and even of edible quality, but many soap makers, past and present, cannot afford that luxury. Soap traditionally has been made from fats that are inedible or otherwise not suitable for human or animal food, so there are methods for how to filter, bleach, wash, refine and deodorize poor quality inedible fats for use in soap making. Some methods are more suitable for large scale soap making, others work fine for small or hobby scale soaping.

If using this type of fat, even after cleaning and deodorizing it, then it's probably a very good idea to use an antioxidant, such as ROE (rosemary oleoresin), and/or a chelator, such as tetrasodium EDTA or sodium citrate, to lengthen the shelf life of the soap.

Production of high quality castile soap from high rancid olive oil. By Adel Y. Girgis. Grasas y Aceites, 226 Vol. 54. Fasc. 3 (2003), 226-233
http://cooklikeyourgrandmother.com/how-to-turn-bacon-grease-into-pie-crust/
www.soapmakingforum.com/showthread.php?p=381830 especially post 15
http://handmadesoapcoach.com/dont-throw-out-that-rancid-oil-make-soap/
http://www.soapmakingforum.com/showthread.php?t=35031
http://www.soapmakingforum.com/showthread.php?t=35257

***

BG -- There's been some recent discussion recently on a different thread about this. Maybe you're thinking of that one.
 

hlecter

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First of all thank you all for your time to answer my questions. This is the first time i am opening a topic like this on this sub-forum section i think... I am really sorry if i made any incovenience...

Yes, the olive oil i am talking about smells rancidity so its better not to use on soaps...

But ->

Also, if you smell the oil, be sure to pour a little of the oil in a little bowl and smell that. Sometimes a bit of oil on the spout or cap turns rancid when the bulk oil inside the container is fine.

***

Hand crafted soapmakers nowadays have the option of using fats that are fresh and even of edible quality, but many soap makers, past and present, cannot afford that luxury. Soap traditionally has been made from fats that are inedible or otherwise not suitable for human or animal food, so there are methods for how to filter, bleach, wash, refine and deodorize poor quality inedible fats for use in soap making. Some methods are more suitable for large scale soap making, others work fine for small or hobby scale soaping.

If using this type of fat, even after cleaning and deodorizing it, then it's probably a very good idea to use an antioxidant, such as ROE (rosemary oleoresin), and/or a chelator, such as tetrasodium EDTA or sodium citrate, to lengthen the shelf life of the soap.

Production of high quality castile soap from high rancid olive oil. By Adel Y. Girgis. Grasas y Aceites, 226 Vol. 54. Fasc. 3 (2003), 226-233
http://cooklikeyourgrandmother.com/how-to-turn-bacon-grease-into-pie-crust/
www.soapmakingforum.com/showthread.php?p=381830 especially post 15
http://handmadesoapcoach.com/dont-throw-out-that-rancid-oil-make-soap/
http://www.soapmakingforum.com/showthread.php?t=35031
http://www.soapmakingforum.com/showthread.php?t=35257

***

BG -- There's been some recent discussion recently on a different thread about this. Maybe you're thinking of that one.
WOW!!! Great as always DeeAnna. So interesting links, thank you very very much.

For what i ve read and understand from the member's "grayceworks" post through his method she cleaned her rancid coconut oil turning it to an unscented clear yellow... But i suppose its suitable for launrdy purposes only...
 
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Steve85569

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Unless I'm having a severe attack of déjà vu, I'd swear I've seen this exact OP before, some weeks ago. Am I nuts?
I was having the same thought. Then again we could both be... well soap makers at least.

If it smells bad now it will smell REAL bad after it's cured soap. Even using it as lamp oil will not get rid of the stench. ( don't ask)
 

TheStat

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I was having the same thought. Then again we could both be... well soap makers at least.

If it smells bad now it will smell REAL bad after it's cured soap. Even using it as lamp oil will not get rid of the stench. ( don't ask)
With oils that smell bad or are rancid you should salt out to get rid of the stench and make the soap lighter in color.
 

nickbar

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For cp soap i used to work with rancid oils and after some months there was DOS, i wont use rancid oil again. Check my last thread...

But for a gls how rancid fats affect the final dilluted soap?
 

DeeAnna

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"... But for a gls how rancid fats affect the final dilluted soap? ..."

If there is an odor to the fat, the odor will carry over in the final soap, whether bar soap or liquid soap. So that's an issue that one needs to deal with before making the soap rather than hope the problem will go away on its own. If you washed the rancid fat to remove the odor causing chemicals, however, the resulting liquid soap should be about the same as if you made the recipe with non-oxidized fats. Only difference I can think of is the soap batter will probably trace faster due to the additional free fatty acids, but otherwise it should dilute and act the same.

Edit -- I want to clarify that fat is rancid when it smells "off" due to the breakdown of free fatty acids into smelly aldehydes and ketones. It's the ~smell~ that is the key point for determining rancidity, although there can also be a color change as well.

But keep in mind, a fat can have higher percent of free fatty acids without necessarily being rancid (smelly). The fat will smell fine and will have little or no color change, but if one could test for free fatty acids, you'd learn the fat has a higher % of FFAs than it did when really fresh. If you've ever made soap that came to trace unusually fast and you can't trace that back to other factors, the unusually fast trace may have happened because the fats had a higher than usual % of free fatty acids.

I won't argue with the preference to make soap with non-oxidized or rancid fats, because that's my preference too. But I do think we have to be realistic -- using super fresh fats with low free fatty acids is no guarantee that the soap won't become rancid or get spots of DOS. There are many other factors that can trigger rancidity/DOS in soap in addition to the quality of the fats.

I do suggest if a person does want to use oxidized or rancid fats for soaping that you first wash the fats to remove most of the smell and color. I also recommend using a low to zero superfat. (I don't have proof -- this is just my opinion only -- but my feeling is that higher superfat soap is at somewhat more risk of overall rancidity than lower superfat soap.) I also think its wise to use an antioxidant and/or chelator in the soap.
 
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penelopejane

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I do suggest if a person does want to use oxidized or rancid fats for soaping that you first wash the fats to remove most of the smell and color. I also recommend using a low to zero superfat. (I don't have proof -- this is just my opinion only -- but my feeling is that higher superfat soap is at somewhat more risk of overall rancidity than lower superfat soap.) I also think its wise to use an antioxidant and/or chelator in the soap.
DeeAnna by "washing" you mean salting out as in the link on post 15 above, is that right?

How do you know that all the water has been removed and all that you have left is oil? Or is this clear when you let it cool and you get a layer of water and a layer of oil?

Does this boiling effect the properties of the oil? (Does changing the fatty acid in an oil change the oil?)
I guess what the original Castile makers did was HP.
Was that because they didn't have or choose to use good quality oil?
Today, if we use good quality oil and CP would we be producing a gentler product or just a more reliable product or an inferior product?
 

DeeAnna

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"...DeeAnna by "washing" you mean salting out as in the link on post 15 above, is that right?..."

I agree with Grayce's method of washing fat to clean it. I don't call it "salting-out" because washing fat is not the same thing as salting-out a soap.

Here's a simple explanation of the difference --

Salting-out soap: Soap is soluble in water, but it is not soluble in brine (table salt + water). When you salt-out a soap, you wash it with plain water to remove impurities and glycerin. You then add salt to the water layer. Since the soap is insoluble in brine, the soap separates from the brine and floats to the top. You HAVE to use salt to salt-out soap.

Washing fat: Fat is insoluble in water and also insoluble in brine. When you wash fat, you want to mix the water/brine layer and the fat layer well enough for the icky stuff in the fat to be washed into the water/brine, but once you stop mixing, the fat and the water/brine will naturally separate. This separation will happen regardless of whether you use brine or plain water -- you do NOT have to use salt to wash fat. The brine is thought to help remove any protein-based impurities from the fat. Adding salt might also help the fat and water layers separate more thoroughly. But adding salt is optional, not required.

"... How do you know that all the water has been removed and all that you have left is oil? Or is this clear when you let it cool and you get a layer of water and a layer of oil?..."

To ensure all water is removed from the fat after washing, first you want to separate the two layers as best you can.

If your fat will solidify at room temp or in the fridge, you can cool the fat until it solidifies and remove the solid fat layer from the water layer.

If your fat won't solidify, then you have to let the pot of fat and water/brine sit quietly for awhile, and then carefully pour or ladle off the fat from the water. In some cases, there may be a cloudy layer of proteins and other impurities that lies between the fat and the water/brine. You will want to also separate that layer from the fat.

In either case, you can then heat the fat to 180-212 deg F (at or just below the boiling point of water). Any water in the fat will boil off, making small popping or crackling sounds. When all popping sounds end, take the fat off the heat. Your fat will then be dry.

If you want to store the fat for a long time especially at room temperature, then the fat needs to be dry to prevent microbial growth and you'd definitely want to do this last drying step. If you're going to use the fat fairly soon to make soap or whatever, I'd skip the last drying step. Less heating of the fat is better. And a small amount of extra water in the fat isn't going to ruin your soap.

"... Does this boiling effect the properties of the oil? (Does changing the fatty acid in an oil change the oil?)..."

Washing doesn't really change the fat or the fatty acids. It just removes water soluble impurities in the oil, which includes the chemicals that cause the rancid odor and some of the chemicals that darken the color of the fat. That said, washing may change the properties of the cleaned fat somewhat. Some of the lighter weight fatty acids are slightly soluble in water, so some of these FAs may be removed with the water. The heating of the fat especially in the presence of water may cause the fat to hydrolyze -- in other words the fat breaks down further into fatty acids and glycerin. To minimize this problem, heat the fat only as hot as is needed and only for as long as needed.

"... I guess what the original Castile makers did was HP. ..."

Old fashioned castile was made with a "boiled" process -- quite different than HP or CP.

"... Was that because they didn't have or choose to use good quality oil?..."

I suppose the old soap makers could have used edible, high quality olive oil and other fats, but there was a lot of competition for the higher grade fats -- they were also used in candles and for food. Soap has typically been made from less desirable fats, including inedible fats and rancid fats, because there is generally not much profit in soap. The kind of fats and the quality of the fats used in soap are driven by their cost.

"... Today, if we use good quality oil and CP would we be producing a gentler product or just a more reliable product or an inferior product? ..."

Like so many things, it depends. A quality toilet soap of the past would be every bit as good as a quality toilet soap made today. You'd probably have seen a lower quality product in the past if you looked at the lower cost soaps of the past.
 
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