Oh Indigo - I love you, but you are strange

Soapmaking Forum

Help Support Soapmaking Forum:

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

Seawolfe

Well-Known Member
Joined
Jan 21, 2014
Messages
3,272
Reaction score
3,030
Location
So Cal
Yesterday we did ghost swirls (patterns made by the soap batter having different lye concs) at the soapy meetup. Hubs was asking for more of his indigo & patchouli lard soap, so I figured I would give it a try.

The lye water had indigo powder (.75 tbs ppo, rounded down), citric acid and sugar added to it before the lye. I made the entire batter first at 40% lye conc, got it to emulsion, added the patch, split half the batter and made the other half 30% lye conc with the addition of more water. Plop swirl in the pot and a little "woop woop woop" with the spoon through the length of the mold to swirl some more. Wrap up gell well and check that night.

I open up to peek and my soap is WHITE?!?!? yeah..... No idea. The next bar pic is what I saw that night when I cut TOO early (but sometimes you just need to see whats going on). The indigo is still very green (the batters were crazy green, you would have thought it was spinach powder).

This morning they were actually ready to cut and check out the fancy swirls on the last two pics! And a white frame on them that apparently is due to soap fairies, or indigo just being weird. But I betcha that fades in 2 weeks. It's definitely not partial gel or ash. Fun stuff :)

Indigo loaf.jpg


Indigo bar.jpg


IMG_2458.jpg


IMG_2459.jpg
 
Last edited:
I hope the white border stays! I doubt it will though. Even if unexplainable, it seems impossible that the indigo won't show up there. Love the swirls!
 
I know it's not what you intended, but I love the result! It would be cool to figure out how it happened so that you could replicate the effect if you wanted to. I'd definitely try it out.
 
Half-Arsed Scientific Theory

Like Jon Snow, I know nothing...but being a research fiend, I have a few ideas.

First, taken from Auntie Clara's blog:
So how does this work? Why is the high water soap darker in colour than the low water soap?
Simply put the answer is that the difference in water content influences the pace at which the soap saponifies and how the soap reacts to ambient heat. The difference in reaction to ambient heat results in different gelling behaviour which in turn results in a shade difference in the final soap.
Those who have read Kevin Dunn’s book Scientific Soapmaking carefully, will know that (everything else equal) a low water soap goes through saponification faster and enters full gel phase at a higher temperature than a high water soap does. In this case the 60C temperature kept in my oven was not high enough to force the uncovered low water soap to enter full gel phase. The high water soap, however, did go through full gel at that temperature. But, even though the low water soap did not go through full gel phase it probably was fully saponified before the high water soap was.
So, by manipulating the water content I was able to manipulate the gelling behaviour and by manipulating the gelling behaviour I was able to manipulate the relative depth of colour in the final soap. That’s pretty cool.
Auntie Clara's blog seems to indicate that the design effect achieved in high-low water soap is the result of one portion achieving gel while the other does not. However, this does not explain the frame.


I skimmed a thirty page pdf titled "Solubilization of Hydrophobic Dyes in Surfactant Solutions". The abstract states:
In this paper, the use of surfactants for solubilization of hydrophobic organic dyes (mainly solvent and disperse dyes) has been reviewed. The effect of parameters such as the chemical structures of the surfactant and the dye, addition of salt and of polyelectrolytes, pH, and temperature on dye solubilization has been discussed. Surfactant self-assemble into micelles in aqueous solution and below the concentration where this occurs—the critical micelle concentration (CMC)—there is no solubilization. Above the CMC, the amount of solubilized dye increases linearly with the increase in surfactant concentration. It is demonstrated that different surfactants work best for different dyes. In general, nonionic surfactants have higher solubilization power than anionic and cationic surfactants. It is likely that the reason for the good performance of nonionic surfactants is that they allow dyes to be accommodated not only in the inner, hydrocarbon part of the micelle but also in the headgroup shell. It is demonstrated that the location of a dye in a surfactant micelle can be assessed from the absorption spectrum of the dye-containing micellar solution.
My quick takeaway was the the indigo might not evenly disperse in a solution that is not homogeneous. This could be a contributing factor to the cool white frame that you got. I would really love for Deanna to chime in with more solid chemistry than I have provided.
 
Last edited:
Yeah Id bet my stickblender that the rind is due to the indigo, not the ghost swirl. The thing is the indigo WAS very very evenly disbursed because I made that solution with the indigo, sugar, citric acid, distilled water and lye the night before - and you bet I blended the indigo in well before anything else, and mixed up the solution again before adding it to the oils.

One idea is that somehow the citric acid (sodium citrate) + soap batter + edges made a difference in pH at the edges due to oxidation, and that indigo color IS pH sensitive. But I dunno.
 
My guess on the rim is that it related to oxidation somehow. It's so even all the way around so I doubt it's a temperature thing since the top was not as insulated at the rest and it's not the water concentration issue because that wouldn't have happened in such a perfect rim without trying.
 
Cool soaps Seawolfe! Woulda been a great entry for last month's challenge! What was the meetup?

Its a local meet up of soapy people here in the So Cal area:
http://www.meetup.com/The-Soap-Collective/

Once a month there is something different to make - liquid soap, clyde slide, zebra swirls etc.. I really really enjoy just going and talking to people about soap, while making soap. Carolyn usually comes too and we tease each other :)
 
Wow, that would be so much fun! Do you have another thread about it somewhere? I'd like to read more about it.

It's probably too sparsely populated where I am at, but I would be totally game for such a thing. I've showed two different groups of friends how to soap recently. All of them have loved it. It is fun to share the craft with people who see the beauty.
 
Seawolfe at the moment my indigo swirl is quite purple did yours go purple after your swamp green, before turning to your pretty blue? Looks to me like your soap did not get a full gel which why the light edge all the way around, it may still change once the ph fully settles. I am sorry my ghostie swirl partially gelled, it is now pretty much 1 color :-(
 
Wow, that would be so much fun! Do you have another thread about it somewhere? I'd like to read more about it.

It's probably too sparsely populated where I am at, but I would be totally game for such a thing. I've showed two different groups of friends how to soap recently. All of them have loved it. It is fun to share the craft with people who see the beauty.

The guy who runs these meetups has been doing them for ages - I just lucked out that its near where I live. Check out http://www.meetup.com/find/ to see if theres anything interesting in your area, or start one!

Seawolfe at the moment my indigo swirl is quite purple did yours go purple after your swamp green, before turning to your pretty blue? Looks to me like your soap did not get a full gel which why the light edge all the way around, it may still change once the ph fully settles. I am sorry my ghostie swirl partially gelled, it is now pretty much 1 color :-(
I get greens and blues- no purple (yet). I do find that since the amount you add is so small (recommended start with 1/2 tsp ppo?), you get big changes when you add a little more or less. Plus it morphs like a crazy thing as the pH changes in the soap - so give it time.

Mine did gel - the heat was from the bottom, so the bottom definitely gelled. Heh and now the edge is turning green... Remember John said if you didnt see a pattern to just put the bar into the bottom of a crock pot for a bit and see if a pattern comes up? He says thats how he did his sample bar.
 
That's interesting. Was that in specific reference to ghost swirls, indigo, or broader than that?

Specific to ghost swirls - he really made his pattern pop by putting an already cut bar flat down in the crockpot for a bit. I had always thought that if you missed the gel window, you missed it.
 
The guy who runs these meetups has been doing them for ages - I just lucked out that its near where I live. Check out http://www.meetup.com/find/ to see if theres anything interesting in your area, or start one!


I get greens and blues- no purple (yet). I do find that since the amount you add is so small (recommended start with 1/2 tsp ppo?), you get big changes when you add a little more or less. Plus it morphs like a crazy thing as the pH changes in the soap - so give it time.

Mine did gel - the heat was from the bottom, so the bottom definitely gelled. Heh and now the edge is turning green... Remember John said if you didnt see a pattern to just put the bar into the bottom of a crock pot for a bit and see if a pattern comes up? He says thats how he did his sample bar.

LOL, forget the purple the indigo is green. The purple was one of those many moments I seem to have to often...purple had something to do with the Wisteria purple mica I used. :oops: :rolleyes: It is a pretty lime green this morning. Last night the indigo was more of a gold
 
LOL, forget the purple the indigo is green. The purple was one of those many moments I seem to have to often...purple had something to do with the Wisteria purple mica I used. :oops: :rolleyes: It is a pretty lime green this morning. Last night the indigo was more of a gold
SEE? Its crazy. I think that gold you are seeing is what makes up my rind. Wait a few days, it will change...
 
Specific to ghost swirls - he really made his pattern pop by putting an already cut bar flat down in the crockpot for a bit. I had always thought that if you missed the gel window, you missed it.

If it is not too much trouble, would you mind providing a link to the post or blog where John discusses this...or a clue to aid me in my search? If it is a post or thread here, I can probably find it myself with a user name. I am also happy to scroll through umpteen pages of a previously undiscovered blog.

In the event that John is a colleague from your meet-up: Do you set the crock pot on it's lowest setting or is there a particular temperature range that you want to stay within?

I do not expect you to spend time hunting anything down, but am not sure that "John" is enough of a lead for me. (Despite it's ubiquitousness, I might have done better on my first search attempt if I had not accidentally left the "r" out of "crock pot" :oops:)
 
Last edited:
If it is not too much trouble, would you mind providing a link to the post or blog where John discusses this...or a clue to aid me in my search? If it is a post or thread here, I can probably find it myself with a user name. I am also happy to scroll through umpteen pages of a previously undiscovered blog.

I do not expect you to spend time hunting anything down, but am not sure that "John" is enough of a lead for me. (Despite it's ubiquitousness, I might have done better on my first search attempt if I had not accidentally left the "r" out of "crock pot" :oops:)

snerk...

Im sorry - "John" is the gentleman who runs and hosts the soap collective meetups at his house, and has been making soap for years and years. Here is a link so you can see him with his parrot: http://www.meetup.com/The-Soap-Collective/members/9464415/
I know - strange, I am referring to an actual face to face discussion about soap :) He put his earlier bar of soap that he made for an example for the meetup (but didnt show a really visible pattern) into a crockpot for a bit (remember the 'r") and the pattern became more apparent. The example was a very striking white on white pattern.
600_445803682.jpeg


I think he said "a few hours on low" but I cant remember for sure regarding time and temp.
 
Last edited:

Latest posts

Back
Top