Is this DOS?

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KimT2au

You bet they die
Joined
Jul 28, 2018
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Location
Perth, Western Australia
I was so impressed by the work in last month's challenge that I thought I would like to try my hand at some soap carving. I decided to make the soap in two sections thinking that when I carved the soap I would hopefully feel the difference in texture and not dig too deeply into the soap. I made a small batch of batter, just enough for two bar, and poured it into a small wooden mould which I lined with baking parchment. I left the soap for 24 hours, unmoulded it, split the soap into 2 bars and then let it (pink/white section) cure for about 10 days.

On Monday I made an even smaller amount of the same recipe (below) which I coloured with black oxide, did not scent, used the same wooden mould which I lined with grease-proof paper (it was an experiment to see if it worked as well as baking parchment), poured in the batter, sprayed the top of the batter with IPA and then pushed the two pink/white bars into the black batter. I let the soap sit overnight in the mould, unmoulded it Tuesday and left it open to the air until this evening (Wednesday evening) when I sat and carved the design. At this point the pink/white section is about 14 days old and the black portion is 3 days old.

What I have found is that wherever the black soap has covered the pink/white soap there are dark spots. The parts of the pink/white soap that did not come into contact with the black soap show no signs of the spots. The pink/white soap showed no sign of discoloration before I placed it in the black batter.

There are a couple of other things that may be relevant. The black batter was the third batch of soap I made that day. I started with an oat milk soap which had no colour added and had a very light fragrance of lavender. I wiped my bowl but was not too careful about it and I didn't wash it and then made a small experimental batch of a chocolate soap which was a different recipe to both the oatmeal and the black soap. The recipe was an experiment of what I hoped to give to family for Christmas and it contained both a little bit of vegan chocolate and some dutch cocoa and was scented with Bramble Berries Cocoa Amber (which is beyond amazing). Then I made the black soap. By that time I was tired and it was a black batter I was making so I did not wipe out my bowl or stick blender as I knew I would be working with a darker colour.

I did not carve the second pink/white bar tonight as I was too tired. I will hopefully get a chance to carve the second soap in a few days time.

I have not forgotten my recipe, it will be below but I guess my questions are: Is this DOS? Does DOS normally start in as little as two weeks? If it is DOS, why is it not showing on the parts of the bar that did not come into contact with the black batter? If it is not DOS, do you think it could be staining from either of the previous batters I made and the fact that I did not wash my bowl and stick blender between batches? If it is DOS, do you have any suggestions on how I can avoid this in future?

RECIPE
CO 76 degree - 24%
PO - 32%
Canola Oil - 44%

Lye:water ratio 2:1
SF5%
1 tspn of salt was added to pink/white batter but not to black batter
Fragrance ratio 3%
Fragrance was Peppermint oil

The first two photos are taken straight after I finished carving, the subsequent photos are after I used a cloth and water to clean the bar up a bit.

DOS 01 adjusted.jpg
DOS 02 adjusted.jpg
DOS 05 adjusted.jpg
DOS 08 adjusted.jpg
 
What kind of salt was added? I've added sea salt (medium grain hoping for texture) to a black charcoal soap I make and it had a very odd effect over time. It wasn't orange, it actually did what salt does and absorbed moisture causing it to "cry" and as time went on and the air dried up it crystalized and on my black soap looks like granite sorta. I can't be sure is that's DOS. Just thought I'd share my experience with using undesolved salt after trace. I've read DOS has an off-putting scent. But I'm not sure. As far as preventing it, how fresh are your oils?
Another thing, what did you use to carve with? And how fresh is the soap? If it's really fresh and could possibly be active Lye and you used a knife that maybe contained aluminum? Just a thought and not from experience by any means. I'm still rather new. Only made my first batch just a year ago. But have ALOT of failed batches. Hope someone can answer your direct question.
 
I once added Turbinado sugar to my soap batter and got yellow spots and weeping around the grains of sugar. I am wondering what kind of salt you added, also.
 
I also just read more into your post, noticed that it's only where the pink and black came into contact. So my thought, is it wouldn't be dos but again just a thought, but I wonder if the salt did the humectant thing and possibly leached the black oxide causing a color change. The thing that makes me think of this, last night I was reading on working with vanilla as I sit here with countless dark brown soaps and in my half asleep daxe , I read that mixing with I think it said oxide with turn it purple. I'm going to run to the halloHall parade and I'll see if I can pull that article back up. It was on the wsp site
 
What kind of salt was added? As far as preventing it, how fresh are your oils?
Another thing, what did you use to carve with? And how fresh is the soap? If it's really fresh and could possibly be active Lye and you used a knife that maybe contained aluminum? Just a thought and not from experience by any means. I'm still rather new. Only made my first batch just a year ago. But have ALOT of failed batches. Hope someone can answer your direct question.

I once added Turbinado sugar to my soap batter and got yellow spots and weeping around the grains of sugar. I am wondering what kind of salt you added, also.

I also just read more into your post, noticed that it's only where the pink and black came into contact. So my thought, is it wouldn't be dos but again just a thought, but I wonder if the salt did the humectant thing and possibly leached the black oxide causing a color change. The thing that makes me think of this, last night I was reading on working with vanilla as I sit here with countless dark brown soaps and in my half asleep daxe , I read that mixing with I think it said oxide with turn it purple. I'm going to run to the halloHall parade and I'll see if I can pull that article back up. It was on the wsp site

I wonder if you might both have hit on part of the problem, if not the whole problem. The salt was plain old iodised table salt, nothing special. I didn't notice that it did not fully dissolve but that is always a possibility. All my oils are less than 3 months old, so they are fresh. The tools are stainless steel, I made a point of checking that before I purchased them. The pink portion of the soap is about 14 days old, while the black is 3 days old.

What also might be worth doing is digging one of the spots out and seeing how deep it goes. Does DOS penetrate the soap do you know?

I guess the thing to do is to make another small batch but leave the salt out and see how that goes
 
Hmmm interesting! What did you use to color the pink section (did I read over that in your first post?) Did you use regular or high oleic canola oil? I once tried a small batch with 100% canola oil (that admittedly wasn't superfresh) and it got dos almost instantly. Maybe there was some kind of interaction between the colorants, or maybe the oxide triggered dos formation?
 
Hmmm interesting! What did you use to color the pink section (did I read over that in your first post?) Did you use regular or high oleic canola oil? I once tried a small batch with 100% canola oil (that admittedly wasn't superfresh) and it got dos almost instantly. Maybe there was some kind of interaction between the colorants, or maybe the oxide triggered dos formation?
No, you didn't miss what colouring I used in the pink section. It occurred to me later I had forgotten to mention it. I used a liquid soap colourant and TD from Aussie Soap Supplies ( https://www.aussiesoapsupplies.com.au/titanium-dioxide-white.html https://www.aussiesoapsupplies.com.au/liquid-brites-ng-hot-pink.html ) and Egyptian Rose Mica from Southern Soap Supplies ( http://southernskiessoapsupplies.co...roduct_info&cPath=118_134_137&products_id=620 ). It was meant to be an in the pot three colour swirl but I over mixed.

Just to be awkward my canola oil was neither regular nor HO but mid oleic. From memory it is about 3% short of being considered high oleic.

Kim
 
One thing that caught my eye was "Fragrance was Peppermint oil." I'm not sure if you saw this recent thread, but it may be worth a look (the soaps I referenced in that thread have what I think is DOS spots that look just like yours. Of course, now I wonder if it might have been the raw sugar I used, but my gut is telling me DOS from the peppermint EO).

https://www.soapmakingforum.com/threads/only-my-peppermint-cp-soaps-develop-dos.71873/
 
One thing that caught my eye was "Fragrance was Peppermint oil." I'm not sure if you saw this recent thread, but it may be worth a look (the soaps I referenced in that thread have what I think is DOS spots that look just like yours. Of course, now I wonder if it might have been the raw sugar I used, but my gut is telling me DOS from the peppermint EO).

https://www.soapmakingforum.com/threads/only-my-peppermint-cp-soaps-develop-dos.71873/
Thanks, @HowieRoll , I read through the thread you sent me and you could well be right. I am rather busy with non-soap stuff at the moment so I think I will avoid peppermint eo until I have more time to experiment.
 
No, you didn't miss what colouring I used in the pink section. It occurred to me later I had forgotten to mention it. I used a liquid soap colourant and TD from Aussie Soap Supplies ( https://www.aussiesoapsupplies.com.au/titanium-dioxide-white.html https://www.aussiesoapsupplies.com.au/liquid-brites-ng-hot-pink.html ) and Egyptian Rose Mica from Southern Soap Supplies ( http://southernskiessoapsupplies.co...roduct_info&cPath=118_134_137&products_id=620 ). It was meant to be an in the pot three colour swirl but I over mixed.

Just to be awkward my canola oil was neither regular nor HO but mid oleic. From memory it is about 3% short of being considered high oleic.

Kim
I have used mid oleic with no problems. I usually depends on the price between HO or Mid or how the wallet is feeling. I happen to really like canola in soap so use it alot.
 
I think I will shelve this recipe for a while and put the soap aside to see what happens over the next 12 months or so. It will be interesting to see if the DOS appears all over the bar or remains only on the parts which were covered by the black batter.
 
@Angela Zeigler DOS can be triggered very quickly by copper. It is good you know aluminium is a problem, but the problem isn't DOS, it is that lye/soap batter dissolves aluminium (quite quickly) and produces undesirable gases and solids (so it still ruins the soap, just differently!).

I like your salt-drawing theory, that has some merit.

@KimT2au
"... If it is DOS, why is it not showing on the parts of the bar that did not come into contact with the black batter?..."

This says to me that the DOS/colour is coming from the black soap, not the pink.

This doesn't rule out the salt being a contributor, but it's not the salt that's the problem directly (if that makes sense).
Perhaps the salt is the means of transferal from the black into the pink (alone the lines of Angela's post #2).

I would check the vegan chocolate for colouring - I've had some colours go that precise DOS colour (without any of the other tell-tale signs of DOS), and if the salt drew the colouring down from the chocolate, you a) won't get dos spots on the bottom of the pink and b) won't get dos spots in the chocolate portion (because it's not dos).

The alternative is that it's still the peppermint oil and it is DOS. The only thing that is stopping me from being very agreeable with this theory is that the spots are quite large for something that would be distributed evenly throughout the soap - I would expect spots on the bottom of the soap as well. Although, perhaps adding the fresh soap on top accelerated the oxidation? That would suggest that the bottom of the soap WILL eventually get DOS as well.

So, it looks like DOS, but could be either colouring from the chocolate soap or DOS that was accelerated BY the (fresh) chocolate soap (and will appear on the bottom of the soap later).

"... It will be interesting to see if the DOS appears all over the bar or remains only on the parts which were covered by the black batter. ..."
Yup.
 
Certainly the greaseproof was not exposed to Lye but it is stored in the cupboard next to the oven. I am not sure if that type of heat would make a difference, plus the oven was not on at the time the soap was made.
 

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