My DOS Challenge Experiments

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Last fall every batch of soap I made (a batch is 50 bars) ended up with DOS. I cried and cried so threw away all my oils I bought in the 35 pound containers and started fresh with new smaller containers from Columbus Oils in Chicago. Stopped using canola and using only Olive with Castor for 1/2 my oils. Haven't had DOS since and really didn't have the heart to try experimenting into which oil it was but it was every batch. You can imagine what I lost with not to mention time but I only use essential oils. Since that time I've been making 1/2 batches because I am still freaking out. I also wonder if those 35 pound containers they send me sat in some hot warehouse for some time waiting to be shipped. Love working with Columbus but another time when I order Castor Oil they went me Avocado Oil and I didn't look at the label so lost that batch before I realized what I was doing.

Oh boy, bountifulsoaps, how aweful! That's heartbreaking to lose every single batch. I'd have done the same and started over with new oils. Since we can never know how long the containers have sat and in what conditions, it can be a crap shoot. Have you considered adding EDTA, citric acid or sodium citrate to your batches? ROE added to the soft oils when opening a new container might be useful too.

My last 3 batches of laundry soap developed DOS which really has me baffled (and angry!). It's simply 100% CO and -1% SF. No additives. I made another batch yesterday, using a new container of CO, and added EDTA at 0.5% total batch weight. Hopefully this fixes the problem for me. I hate the waste of ingredients and time when I have to toss soap due to DOS!
 
Thanks for posting your results, Kristay!

Just last night, I went through my box of sample bars that contained one from each batch I've ever made. they have been stored together unwrapped in a cardboard box inside of a cabinet. Our humidity here is also very low and the house is kept between 60 - 80 degrees.

I don't use any of the oils you're testing. The only batches that show DOS for me had hemp at 15% in a high lard recipe with goat milk. These were from before I used EDTA or any other chelator or ROE. Those recipes did have less than 15 Linoeic + Linolenic and still got DOS. Hemp is permanently off my soaping list now.

Pumpkin Seed Oil + Pumpkin Puree were fine.
Various liquid replacements soaps were all fine in any combination: goat milk, coconut milk, aloe, calendula tea.
Heavy Cream @ 1/2 liquid always smelled terrible to me. Time has made it even worse. There wasn't DOS, but the rank butryic acid smell is overwhelming.

Oils that were fine for me ( these comprised at least 10% in various recipes):
Avocado Oil
Castor Oil
Lard
Mango Seed butter
Olive Oil
Cocoa Butter
Shea Butter
Coconut Oil
Sweet Almond Oil
PKO
Stearic Acid
Jojoba oil
 
Last fall every batch of soap I made (a batch is 50 bars) ended up with DOS. I cried and cried so threw away all my oils I bought in the 35 pound containers and started fresh with new smaller containers from Columbus Oils in Chicago. Stopped using canola and using only Olive with Castor for 1/2 my oils. Haven't had DOS since and really didn't have the heart to try experimenting into which oil it was but it was every batch.


How horrible for you! I think you did the right thing though throwing everything out.
I went to an Asian food market the other day and there was an off bottle of coconut oil. Boy, the whole aisle stank! Obviously oils don't have to get that bad before they are off. I once threw out a bottle of oil that had gone cloudy. I guess I'm a bit paranoid about the idea of DOS even though I've never had it.
I put ROE in anything I'm not going to use within 3 months or so and I use citric acid too.
 
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There are soooo many triggers for DOS, and it's almost impossible to eliminate every single culprit. Sometimes I get the impression that some soapers like to think only "bad soapers" get DOS, but the way I see it, if a soaper hasn't seen any DOS yet, it's just a matter of time!

I keep the linoleic acid content reasonably low, use ROE antioxidant in many of my oils, and refrigerate my fats if possible. That's going to do a lot to prevent the all-over DOS due to oxidized fat. I also use distilled water and am cautious about the EOs I use in soap. Some EOs (lavender being one of them) when they become oxidized can accelerate all-over DOS. As much as possible, I store finished soap in covered containers or get it packaged in shrink wrap, handle it with freshly washed hands, and keep it away from light. I use EDTA (or one could use citrate) as insurance for all-over DOS as well as those freckles of DOS caused by small bits of contaminants. I think these things have done a lot to reduce DOS in my soap.
 
Sometimes I get the impression that some soapers like to think only "bad soapers" get DOS, but the way I see it, if a soaper hasn't seen any DOS yet, it's just a matter of time!

Uhm... I have not experienced DOS yet. Halp *_*

I guess it is just waiting around the corner for me, ready to jump out from behind a door or dark corner, and raise it huge ugly DOS'y hands at me - ready to strike at any moment, with spots, brown goo and smelly things...??

Awesome.

*Cue in omnious music from Hitchcock Psyko - The shower scene*

Sneaks off to check on all teh little soapies before tucking them safely back into their beds... I mean boxes!
O_o
 
Thanks for posting your results, Kristay!

Just last night, I went through my box of sample bars that contained one from each batch I've ever made. they have been stored together unwrapped in a cardboard box inside of a cabinet. Our humidity here is also very low and the house is kept between 60 - 80 degrees.

I don't use any of the oils you're testing. The only batches that show DOS for me had hemp at 15% in a high lard recipe with goat milk. These were from before I used EDTA or any other chelator or ROE. Those recipes did have less than 15 Linoeic + Linolenic and still got DOS. Hemp is permanently off my soaping list now.

Pumpkin Seed Oil + Pumpkin Puree were fine.
Various liquid replacements soaps were all fine in any combination: goat milk, coconut milk, aloe, calendula tea.
Heavy Cream @ 1/2 liquid always smelled terrible to me. Time has made it even worse. There wasn't DOS, but the rank butryic acid smell is overwhelming.

Oils that were fine for me ( these comprised at least 10% in various recipes):
Avocado Oil
Castor Oil
Lard
Mango Seed butter
Olive Oil
Cocoa Butter
Shea Butter
Coconut Oil
Sweet Almond Oil
PKO
Stearic Acid
Jojoba oil

Oooohhh, thanks for this list snappy! I haven't done any specific tests with these oils but have used all (except lard) in many recipes with no problems. Good to know your results mirror mine.

The difference for me is the hemp oil. I use it in my "hippie line" at 15% (all are scent blends using "Mary Jane" FO) and haven't had any DOS problems with it. But I immediately put the bottle in the freezer when I receive it and add ROE when I open it. Maybe that's what has made the difference for me. None of my hippie batches have EDTA. So hemp stays on my soaping list. :)

Based on your description of heavy cream, I'm glad I haven't tried it! :sick:
 
Because of the advancement in forensic science and DNA transfer, we know we leave our DNA behind every time we touch something. The transfer comes in the form of sloughed epidermal epithelius (skin cells). These cells harbor microbes, both good and bad. Proper handwashing is excellent at keeping the microbes at bay but can't remove them all. So as an added layer of protection, I handle all my unwrapped soaps with gloved hands. It may or may not make a big difference in the end but I feel better knowing my hands aren't adding extra possible contaminants. There are enough environmental factors I can't control, like air contaminants, so I chose to use gloves to help eliminate one other possible source that may lead to DOS. It might be a bit OCD of me but I'm okay with that! :)
 
I am very disappointed that last night I discovered DOS in 2 of the 5 different soaps I made at the Soapmaking Bootcamp I attended only 4 months ago! I was shocked to say the least.

I have looked at the recipes used in all 5 soaps to see if there is a factor that I could isolate in the 2 batches that would single out from the others. I cannot really be sure what happened to cause DOS in the 2 batches. Well, one common denominator is that all the oils, colorants, fragrances, scales, utensils, tools, etc. were provided by the instructor. All the pre-printed recipes were provided by the instructor. I have run them through SoapCalc and am satisfied they are not bad recipes, but that doesn't seem to be very helpful in isolating the cause. Well maybe. I have my doubts about the scales we used. They didn't seem very reliable to me, so perhaps measurements could have been off by a lot as the amounts for each batch were fairly small. One pound batches for the most part is what we made. There was a two-pound batch, and a couple soaps from it have DOS spots.

All soaps were made on either Jan. 16 or 17 this year.

Out of the 5 soaps made, one was a repeat. Meaning I/we did that recipe twice. Of 2 batches with the exact same recipe, one has DOS spots and one does not. That was the 2-pound batch that developed DOS. The other soap with DOS was a one pound batch. It was also the only one I made with Almond Oil out of all 5 soaps that weekend. So I suppose it could be the almond oil was off, but it just seems unlikely, given the amount of oils the instructor goes though regularly.

The only difference between the two batches where one has DOS and the other doesn't is that a discoloring fragrance was added to the one without leading to a dark soap, so it could have DOS and I just can't see it; it also has jojoba beads incorporated in the soap. The oils in this recipe were repeated in other recipes that did not develop DOS, so I don't think it was the oils.

Another factor, that of course could have been effected by (possibly) the scale, was the superfat for each recipe, One recipe has 5% SF, while the other has 7% SF. If measurements were way off because of the scales, that could account for a higher likelihood of DOS, I suppose.

Then of course, other factors I have not even considered could have come into play. I or my partner could have made errors while making the soap. Possibly, but other than the DOS spots on a couple of them, the soaps are really nice. I won't blame any of the people involved. I'm blaming the scale for wont of knowing what else it could be.

They all smell fine, so I am going to have to use these soaps asap before they can't be used. I have actually been using one of them already, but didn't expect to have to use them up faster. What a bummer!

I ordered my ROE today and it should arrive on Friday. I will be diligently adding it to all my jugs of oils immediately thereafter.
 
Even commercial soap makers use chelators and antioxidants in their soap nowadays. Soap making manuals of 100 years ago also mention discoloration and odor problems. So it's nothing new and nothing limited to handcrafted soap makers.

Although any kind of rancidity is caused by the oxidation of the soap and fat molecules -- the two different forms likely have different triggers. If soap develops an OVERALL rancidity, that's one thing that I believe can be traced to ingredients. Antioxidants will be a great help in preventing overall rancidity. If the soap gets freckles -- truly those Dreaded Orange Spots -- that I believe is more likely caused by trace contaminants. Handling this kind of problem is the strength of a chelator.
 
I don't use any of the oils you're testing. The only batches that show DOS for me had hemp at 15% in a high lard recipe with goat milk. These were from before I used EDTA or any other chelator or ROE...Hemp is permanently off my soaping list now.

Maybe it's good you brought this up. Personally I think that the recommendation of linoleic + linolenic < 15% is probably misleading. It suggests that these two fatty acids might be reasonably equivalent. That really is not true.

A linoleic oil like soybean is still a general-purpose oil. It can be used for salad dressing or frying or even as a significant component of shortening. You can get away with using some for soaping, and in a clever recipe you might even use a little advantageously.

True linolenic oils are never used to make soap, and oils rich in linolenic only occasionally are. A real linolenic oil like flax/linseed can be used for things like oil paint. It's called a "drying oil" because on exposure to oxygen a thin layer of it quickly polymerizes and becomes solid as if you applied varnish or plastic (like polyurethane) to the surface. That's how reactive it is with air.

More realistically, the suggested target should be linoleic + linolenic less than 15%, but with linolenic preferably as close as possible to zero.
 
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Interesting!

These are oils from my notes that are relatively high in linolenic acid (in DESC order) :

Pomegranate Seed Oil
Perilla Seed Oil
Flax Oil, linseed
Linseed Oil, flax
Sacha Inchi, Plukenetia volubilis
Camelina Seed Oil
Sea Buckthorn Oil, seed
Cranberry Seed Oil
Rosehip Oil
Kukui nut Oil
Black Current Seed Oil
Raspberry Seed Oil
Hemp Seed Oil

From that list, hemp is the only one I've tried or routinely seen used in soap making recipes.
 
Based on the interesting info from TOMH regarding linoleic and linolenic fatty acids, (plus reading DeeAnna's informative posts many times on the subject) I realized I never actually calculated the percentage of each in my Hippie Soap recipe. So off to soap calc I went.

When I looked at the FA profile for hemp oil alone it shows linoleic 57 (58.2%) and linolenic 21 (21.4%). That's a total of 79.6% for both FA's. My first thought was "holy crap, that's high!" Well it would be if you made 100% hemp oil soap. Then I input my Hippie Soap recipe using hemp oil at 15%. That came up with linoleic at 16 (16.6%) and linolenic at 3 (3.1%) with a total of 19.7%. I'm still over the goal of 15% but not by a huge amount. If I use only 10% hemp my recipe goes down to linoleic 14 & linolenic 2 which comes out to a total of 16.5%. I feel better knowing the linolenic (with either percentage I use) is very low. Since I haven't gotten DOS in my hemp oil recipe (knocking on wood!) I'm going to stick with using it at 15%.
 
Even commercial soap makers use chelators and antioxidants in their soap nowadays. Soap making manuals of 100 years ago also mention discoloration and odor problems. So it's nothing new and nothing limited to handcrafted soap makers.

This is actually a great point to remember if anyone starts to roll their eyes at handmade soap because it is so... "handmade" compared to the massproduced factorymade soap items.

Thanks for including this little snippet of info : )
 
Tell me about these antioxidents? I've never used them and am interested in buying.
What I have done in all the new batches done which does not have DOS after several months is I've taken out both Canola and Palm Kernel in my recipe. I now used 1/2 Olive/Castor and the rest Palm, Coconut and Shea. I keep wondering if the Canola did it or was it just a bad 35 pound container I bought of one of the other oils. I buy my Olive at Sam's and who knows about how long thats been out. What about eos, can they go bad and cause DOS too?

I batches use to be 10 pounds of Oils and all the last batches which is about 15 batches I am using 5 pounds of oil just in case. I almost gave up soap making because of all those DOS batches. I have a few stores I sell out of but mainly make soap because I've always loved it until all those DOS batches!!!!!!!!!!
 
Tell me about these antioxidents? I've never used them and am interested in buying.
What I have done in all the new batches done which does not have DOS after several months is I've taken out both Canola and Palm Kernel in my recipe. I now used 1/2 Olive/Castor and the rest Palm, Coconut and Shea. I keep wondering if the Canola did it or was it just a bad 35 pound container I bought of one of the other oils. I buy my Olive at Sam's and who knows about how long thats been out. What about eos, can they go bad and cause DOS too?

I batches use to be 10 pounds of Oils and all the last batches which is about 15 batches I am using 5 pounds of oil just in case. I almost gave up soap making because of all those DOS batches. I have a few stores I sell out of but mainly make soap because I've always loved it until all those DOS batches!!!!!!!!!!

1st off, bountifulsoaps, DON'T GIVE UP! There are so many things that can contribute to DOS and it can take some fiddling with ingredients, method and storing conditions to figure it out. (to name a few) Then there are those random batches when DOS rears it's ugly head and you can't figure out the exact culprit.

In this experiment I used regular canola (not high oleic) which did develop DOS for me. I've since switched to HO canola and have no DOS at this point. So possibly your canola is the culprit. But as you pointed out, we can't know how long any oils have sat on store shelves and what conditions they may have been stored in (like a hot warehouse or sunny outdoor area).

As far as EO's causing a problem, DeeAnna talks about oxidized lavender EO contributing to the problem in post #24 of this thread.

If you aren't using distilled water, you should. The minerals in some other types of water can contribute to DOS.

The use of ROE (rosemary oleoresin) can be found in this thread:

http://www.soapmakingforum.com/showthread.php?t=58835&highlight=rosemary+oleoresin

The use of tetrasodium EDTA can be found on this thread:

http://www.soapmakingforum.com/showthread.php?t=58975

I hope this helps!
 
Another major cause of DOS is storing on metal shelves and another is not letting the soaps get ventilation.

A lot of posts say "I stored it in a cardboard box and 3 months later it had DOS". Our oils have production and/or use by dates but as others have said you can't tell how they were stored in the warehouse.

Thanks DeeAnna and KristaY for the advice about using gloves on your curing soap. I move my soap around a lot ([emoji2][emoji2][emoji2]) and will do this from now on because I really dread the appearance of DOS! Touch wood.
 
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Well I found one problem that can lead to DOS. I always buy my lye from Red Devil in IL. I always use MMS lye calculator. Well, in march I made a lot of soap and only one is getting it. I used lye bought from another maker and used MMS calculator. Well, after that batch I just didn't like that lye so immediately went back to my other lye. That one batch is getting it. So, I went to the maker's lye calculator and it says to use a lot more than I did so it didn't have enough lye in. I discount at 5% on MMS's calculator but on the lye I had bought it said
I had discounted at a higher than 10%...goes to show if you change lye besure to use their calculator.
 
DeeAnna - are you referring to sodium citrate? How do you list this ingredient on your soap label? My recipe (with hemp at 6%) reflects Linoleic 11 and Linolenic 2. Would it be safe to say that using .01% ppo would help keep DOS away? At what phase would I add the citrate?

Sorry for all the questions but I've never used sodium citrate before.
 
I use SC at 2% ppo. It helps with scum tremendously and dos. I add it to water alongside sugar and silk. Stir to dissolve, add lye after. I still get dos (high lard) when i leave a soap in a non breathing dish (bowl) for multiple months and multiple uses. I think this is more caused by remaining in high hard water in the bowl. Over time those minerals get to the soap. It doesn't happen to my shower soaps left on a side and turned each use.
 
There are soooo many triggers for DOS, and it's almost impossible to eliminate every single culprit. Sometimes I get the impression that some soapers like to think only "bad soapers" get DOS, but the way I see it, if a soaper hasn't seen any DOS yet, it's just a matter of time!

I keep the linoleic acid content reasonably low, use ROE antioxidant in many of my oils, and refrigerate my fats if possible. That's going to do a lot to prevent the all-over DOS due to oxidized fat. I also use distilled water and am cautious about the EOs I use in soap. Some EOs (lavender being one of them) when they become oxidized can accelerate all-over DOS. As much as possible, I store finished soap in covered containers or get it packaged in shrink wrap, handle it with freshly washed hands, and keep it away from light. I use EDTA (or one could use citrate) as insurance for all-over DOS as well as those freckles of DOS caused by small bits of contaminants. I think these things have done a lot to reduce DOS in my soap.

You package your soap so it doesn't get air? Not to say its not done, its just that I have read that soap needs air to cure, so after cure it's ok? I package my soap in shrink wrap too, I love it, and the one one that I have, just lately, had an issue with is the the lavender and a little with ginger eo. Interesting.
 

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