How on earth did she make this color?!

[szaza]

I was watching the soap challenge club entries for June and saw this amazing soap by ChezHelene

The blue color especially struck me, since it's really hard to get such a color with only natural colorants. In the video she says she added an alkanet infusion to the oils, then she blends in blueberry puree and mixes in her masterbatched donkeymilk lye solution. She also gels the soap.
This has me stumped. I've never tried that exact combination of additives, but I can't really imagine how that combination can get such an amazing shade of blue!
Alkanet normally makes a purple soap. It sometimes turns blue (I've had that happen once) to turn purple after about a week. If the picture was taken in the first week, that could be the reason for the blue. Though alkanet is very finicky and any hint of tan in the soap can make it turn grey or brown. I'm surprised the donkey milk didn't affect the color.
When I tried blackberries in soap, they turned a mauve brown and when I look for examples of soaps colored with blueberries, they're all brown.. if the donkey milk didn't dull the alkanet, the blueberries probably should have. Maybe they only turn brown after a while, something with pH or air exposure?
Does anybody here have experience with donkey milk and how does it affect color?
How about blueberries?

 

[BattleGnome]

In her “all natural” soap making book SoapQueen uses blueberries but I don’t remember them getting that dark. But she also makes a note that she uses mica along with the berries to get her colors because Brambleberry micas are “nature identical” or something similar.

I don’t think that’s any help unless some fantastic gel was involved that I havent mastered

 

[dibbles]

I tried this challenge, and I know that for the advanced category, which Helene entered, only natural colorants could be used. So no micas were involved. I used blueberry puree and alkanet in one of my attempts, but got the purplish color you would expect. I used a blueberry tea instead of milk.

Toward the end of the video, she shows a second batch made with honey instead of maple syrup which darkened the white layer to a tan color, but the blue is pretty consistent in both batches. One of my tries made the alkanet appear a teal/bluish color for a few days (maybe up to a week), so I'm going to guess that her photos were taken pretty close to the time she made the soap.

 

[szaza]

Thanks @BattleGnome ! My initial idea was there must be some mica in there, but she entered in the advanced category and for that category only natural colorants were allowed as @dibbles just said (I don't think 'nature identical' counts there)
By the way, @dibbles thanks for chiming in! I just saw your entry and was thinking I wanted to ask you about it and then I saw you answered already I really like the soap you entry by the way!
It looks like the donkey milk is the only variable that can possibly be responsible for the intense blue. This is going on my list of soapy things to try! (Once I find out where to get fresh donkey milk.. shigh)

 

[Mobjack Bay]

I’m in late on this, but I seem to recall that in her e-book, Jo Hauslauer says she uses goat milk in her recipes in order to get the best natural colors. She also says it’s important to use the clearest oils possible. I wonder if there’s something in milk, or donkey milk in particular, that helps with the purples and blues. Casein is used to make milk paint and the colors are very long lasting. I poked around but didn’t learn much except that a primary pigment in alkanet, alkannin, is an alcohol soluble (source) napthoquinone (source). I also learned that casein can be used to make fiber (source), which seems totally irrelevant right now, but interesting nonetheless.

 

[penelopejane]

Even if you do get that blue with alkanet and blueberry it will fade in 4 -6 weeks. Sorry to say

 

[Mobjack Bay]

I wonder if anyone has used goat milk in a soap colored with alkanet.

 

[szaza]

I wonder if anyone has used goat milk in a soap colored with alkanet.

I have. It turned greyish brown and stayed that way (left part is alkanet, the orange is annatto)

 

[SoapySuds]

Saturation pulls out colors in photos.

Similar to the processing done in photos for listings for houses.

Notice that she didn’t show the actual slicing, just the finished product, in still photos.

Before you see the end cut product, look at the layers in the loaf, she didn’t color process her video like those last photos.