Indigo pink

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My indigo did give pink in isopropanol so I guess the pigment is in the plant? I also get very saturated blues with this indigo, so I'm assuming it has a high dye concentration. I do shake every few days (doing cold infusion) so that's probably it! ;)
The shaking is probably the problem. Shake it for a few days or maybe a week(?) at the beginning and then let it settle until you see only pink. And then you will need to avoid stirring up any of the blue powder when you decant the oil. The soap I made was 30% OO and I replaced 40% of the OO with the pink infused oil. That’s 12% of the oil in the total batch as the pink infused OO. I’ve since read somewhere that with a strong color infusion its best to aim for 15% of the total fats. My infusion looked fine in the total oil mix, but the soap turned out very pale. I think the solution is to replace more of the olive oil, or make a stronger infusion.
 
The red pigment from indigo producing plants is called indirubin, per the article linked below.

This is a useful technical article on indigo pigments. The authors analyzed the pigments in two species of indigo plants. They used four different methods to extract the pigments and found that fermentation of fresh leaves in water yielded the most pigment for the two species tested, which were Indigofera tinctoria and Strobilanthes flaccidifolius. I can't recall any mention of the second species in anything else I've read with respect to dyeing or soapmaking.

Indigo.jpeg

This information from the Results and Discussion section of the paper (pg 113 in the paper) provides a possible explanation for low color yield from dried plant indigo powder:
"So, in the dyeing process, the indigo blue must be base oxidized to leuco indigo which is colorless and dissolves in water before dyeing. After that the leuco indigo is oxidized by the air and turns to be indigo blue again (Phutrakul et al., 2002). The enzyme could come from the indigo plants and maceration of fresh indigo plants would release the glycolytic enzyme from the plant cells to hydrolyze glycan and gave indoxyl which was air oxidized to indigo blue. The enzyme in dried and semi-dried indigo plants might be inactivated during drying process; therefore the yield of the indigo dye from such plant materials was very low."
 
I haven't tried do dye soap with indigo, blue or pink, but have been dyeing textile with indigo producing plants Japanese indigo Persicaria tinctoria and woad Isatis tinctoria. I sometimes get pinks with each of them but can't know when to expect it and when not.
I extract the blue from fresh leaves with warm water alkalinized to a pH about 9-10. Indigo obtained in this way must first be reduced to white indigo which is soluble in water (blue indigo is water insoluble) and then oxidized in air to turn blue. I don't use bought indigo powder that I could infuse oil with.
Any expert out there thas has experimented with fresh indigo leaves?


Ladka and Mobjack Bay
Is it possible to reduce the indigo powder as per a cloth dyeing vat and then concentrate it (maybe dry it) it over the stove to bring it back to blue. Or when it dries out after it is reduced will it stay green and turn the soap green?
 
Good question! Wish I knew the answer :).
I was hoping someone had tried to do it. :)

When you reduce indigo to make a dyeing vat you turn the blue powder into a green liquid that changes the clothes to green but as they oxidise they change to blue.
Probably if I try it (and waste all the ingredients) it will turn green and stay green.
 
I was hoping someone had tried to do it. :)

When you reduce indigo to make a dyeing vat you turn the blue powder into a green liquid that changes the clothes to green but as they oxidise they change to blue.
Probably if I try it (and waste all the ingredients) it will turn green and stay green.
It’s the part about trying to concentrate or dry the solubilized form from the vat that I wonder about. The state of the vat seems to be important for getting the right color when the fabric comes out.
 
It’s the part about trying to concentrate or dry the solubilized form from the vat that I wonder about. The state of the vat seems to be important for getting the right color when the fabric comes out.

I thought you could just "boil it dry" over a very gentle heat. The problem is they say don't let it go over 160*F. So I am guessing it will take a while. I have a dehumidifier maybe I could work out a way to use that. My big problem now is I have a pH tester kit for my fish that doesn't go above 8. I've ordered a pH meter but it will take 30 days to arrive. Don't know how to tell it is 10 for the first stage of reducing the indigo.

I am doing all this because I don't want to use synthetic indigo crystals. Maybe an easier solution is to just by botanical colours indigo.
 
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In my experience and knowledge, it is more important for pH of indigo solution not to drop to go acidic. pH 8 is in the alkaline range so it sould work. A higher pH should do no harm to indigo.
 
Hi everyone, first post though I've been soaking up your knowledge for months.

I grew woad this year (UK) to colour my soaps and extracted the blue pigment from the leaves. I used the method of processing the leaves within an hour of picking. Tear the leaves and put into 90C water (with lid on) for 10 mins then squeeze the water out, mix in soda crystals then stick blend for a while. Let the bits settle then take out the top water and put more fresh water in, leave to settle, repeating until the water is clear. Then remove as much water from the top as possible and dry the paste until totally flaky and dry. Grind into powder and you're done.

It works but I didn't get a massive amount of powder, though I harvested a month too late. It works great though. Beautiful deep blues or pale pastel ones, no grey. I'll harvest again in the spring and hopefully get a better yield.

I couldn't find the page I followed but this is the same method:
http://www.thomaskeyes.co.uk/index.asp?pageid=689263

Glad to be here with you all - I've learned so much thanks. Sam
 
Hi everyone, first post though I've been soaking up your knowledge for months.

I grew woad this year (UK) to colour my soaps and extracted the blue pigment from the leaves. I used the method of processing the leaves within an hour of picking. Tear the leaves and put into 90C water (with lid on) for 10 mins then squeeze the water out, mix in soda crystals then stick blend for a while. Let the bits settle then take out the top water and put more fresh water in, leave to settle, repeating until the water is clear. Then remove as much water from the top as possible and dry the paste until totally flaky and dry. Grind into powder and you're done.

It works but I didn't get a massive amount of powder, though I harvested a month too late. It works great though. Beautiful deep blues or pale pastel ones, no grey. I'll harvest again in the spring and hopefully get a better yield.

I couldn't find the page I followed but this is the same method:
http://www.thomaskeyes.co.uk/index.asp?pageid=689263

Glad to be here with you all - I've learned so much thanks. Sam
Makes me want to try growing woad or indigo!
 
The woad seed only remains viable for a year, so do make sure you use fresh seed. They're lovely plants that are easy to grow - they send a deep tap root down so very soon you don't even need to water them. They've a lot of medicinal anti-microbial properties as well. They're a member of the cabbage family, but the cabbage white butterflies largely left them alone.
 
It’s the part about trying to concentrate or dry the solubilized form from the vat that I wonder about. The state of the vat seems to be important for getting the right color when the fabric comes out.
So what I did was follow the instructions on this website for making an indigo vat:
I experimented with reducing indigo.
http://www.wearingwoad.com/creating-a-natural-indigo-dye-reduction-vat/
To 300ml water add 1 Tablespoon washing soda (sodium carbonate). Use 100g of that mix and add 2/3 tsp indigo(3.75ml). When wetted out add 1/2 tsp RIT. It was green at this stage. Leave for 30 mins then aerate it with a tiny motor attached to a plastic tube. It turned a dark blue liquid. At this stage it can be strained out through a coffee filter and dried in a dehumidifier as msc links to above.

I used 1/8 tsp of this mix in the following 10g batter on the right and 1/4 tsp of this mix on the left:
indigo hearts.jpg
In real life the one of the left is a really dark, dark blue. The one on the right is a paler blue. The batter was left over so it isn't great quality soap.

Interestingly I tried to scale this up and used the mix in a larger batch but I didn't use enough and it turned out green. The advantage of this method is you use far less indigo to make the same colour in soap. Disadvantages are it is difficult to keep the mix in suspension to get the same amount of indigo in the tsp of mix. Might work better with a more concentrated indigo mix in the beginning or drying it.
 
So what I did was follow the instructions on this website for making an indigo vat:
I experimented with reducing indigo.
http://www.wearingwoad.com/creating-a-natural-indigo-dye-reduction-vat/
To 300ml water add 1 Tablespoon washing soda (sodium carbonate). Use 100g of that mix and add 2/3 tsp indigo(3.75ml). When wetted out add 1/2 tsp RIT. It was green at this stage. Leave for 30 mins then aerate it with a tiny motor attached to a plastic tube. It turned a dark blue liquid. At this stage it can be strained out through a coffee filter and dried in a dehumidifier as msc links to above.

I used 1/8 tsp of this mix in the following 10g batter on the right and 1/4 tsp of this mix on the left:
View attachment 42105
In real life the one of the left is a really dark, dark blue. The one on the right is a paler blue. The batter was left over so it isn't great quality soap.

Interestingly I tried to scale this up and used the mix in a larger batch but I didn't use enough and it turned out green. The advantage of this method is you use far less indigo to make the same colour in soap. Disadvantages are it is difficult to keep the mix in suspension to get the same amount of indigo in the tsp of mix. Might work better with a more concentrated indigo mix in the beginning or drying it.
It does sound a bit complicated compared with using the powder, but both are pretty blues! Are you going to try it again in a larger batch? Will you show us the green soap :D
 
So what I did was follow the instructions on this website for making an indigo vat:
I experimented with reducing indigo.
http://www.wearingwoad.com/creating-a-natural-indigo-dye-reduction-vat/
To 300ml water add 1 Tablespoon washing soda (sodium carbonate). Use 100g of that mix and add 2/3 tsp indigo(3.75ml). When wetted out add 1/2 tsp RIT. It was green at this stage. Leave for 30 mins then aerate it with a tiny motor attached to a plastic tube. It turned a dark blue liquid. At this stage it can be strained out through a coffee filter and dried in a dehumidifier as msc links to above.

I used 1/8 tsp of this mix in the following 10g batter on the right and 1/4 tsp of this mix on the left:
View attachment 42105
In real life the one of the left is a really dark, dark blue. The one on the right is a paler blue. The batter was left over so it isn't great quality soap.

Interestingly I tried to scale this up and used the mix in a larger batch but I didn't use enough and it turned out green. The advantage of this method is you use far less indigo to make the same colour in soap. Disadvantages are it is difficult to keep the mix in suspension to get the same amount of indigo in the tsp of mix. Might work better with a more concentrated indigo mix in the beginning or drying it.

So cool that you managed to make blue soap with the indigo plant matter! It does sound like a lot of work, but the idea of making soap with home grown indigo is awesome!
 
Penelopejane, I saved your procedure to use it next year when indigo and woad grow again. Your blue soap is marvelous!
 
So cool that you managed to make blue soap with the indigo plant matter! It does sound like a lot of work, but the idea of making soap with home grown indigo is awesome!
No I used a bought indigo powder that is blue but makes greyish blue soap.
What I was trying to do was make it darker (like Dharma trading indigo pre-reduced crystals but natural) and it turns out it makes it darker and you can use a lot less indigo with this method.
 
Penelopejane, I saved your procedure to use it next year when indigo and woad grow again. Your blue soap is marvelous!
^^^see not above. I didn't use green indigo. It was indigo blue powder - indigo naturalis.
I am about to buy some organic indigo from dharma trading so I will see if it gives a good blue without the rigmarole.

Dharma trading says you can make your own blue indigo powder from the plant so hopefully yours will be a success.
 
I've taken photos of my woad soaps but my phone isn't connecting unfortunately.

I add the blue woad powder at trace...

0.5g of blue woad powder per 300g oils -> pale blue
1g of blue woad powder per 300g oils -> medium blue
1.5g of blue woad powder per 300g oils -> dark blue

I've run quite a few batches now and they always come out blue rather than grey. It doesn't seem to make any difference to the colour whether they go through gel phase or not.
 

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