What’s the madder with my madder?

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I read that alizarin, the red pigment in Madder, is most soluble in organic solvents. Not wanting to use something toxic in my soap :), I thought I would give alcohol a try. It looked promising from the very beginning because the “solvent” turned deep red immediately. I think it should last as well as any madder infusion or tea. The clay idea grew out of reading articles about the evolving use of clays to remove dye from wastewater in treatment plants. Kaolin is not the best clay for scavenging dyes, but it seems to have worked at adsorbing(?) the alizarin in the tincture, which was fairly weak in my test. Next time I will try clay that is “activated” by gentle heating. There’s a possibility that some of the dye could get into the clay mineral if I do that, maybe... I thought I knew a lot about clay, but I don’t, which means I have more reading to do if my brain doesn’t break first :eek:
 
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I love the idea of making a tincture with alcohol and a really pretty pink you got with it as well!
 
You do know that alcohol will react badly with lye right? It can't be used in CP.

You'll need to figure out a way to remove the dye from the alcohol. I'd mix it with some oil and gently heat it until the alcohol evaporates.
 
You do know that alcohol will react badly with lye right? It can't be used in CP.

You'll need to figure out a way to remove the dye from the alcohol. I'd mix it with some oil and gently heat it until the alcohol evaporates.

I gave my method in this post above. As I noted, I used 50% isopropyl:50% water to make the tincture and then evaporated the alcohol off by gently heating it in a Pyrex dish that was sitting in a water bath. I’m not a trained as a chemist, but based on what I have read in the scientific literature, the alizarin dye extracted from madder root is not soluble in oil until it has been transformed into a “lake pigment” by precipitating it on to a metallic salt. Pure alizarin is highly soluble in organic solvents, like chloroform, DMSO and some alcohols, and somewhat less soluble in water. For example, see this chemical reference for pure alizarin.
 
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I think the tincture could be very promising for adding plant colorants to hp soap after cook..[emoji848] do you think it could work with other colors as well? (Like indigo, spirulina,..)
 
I think the tincture could be very promising for adding plant colorants to hp soap after cook..[emoji848] do you think it could work with other colors as well? (Like indigo, spirulina,..)

This will probably be much more than you wanted to know, but that’s the way it is for me once I get started on something I find interesting :)

The various kinds of plant pigments differ in their solubilities in different kinds of liquids, which can include “organic solvents,” alcohols, oil, water. They also vary in stability as a function of light, pH and other variables. It’s definitely complicated and many doctoral dissertations and scientific papers have been written on plant pigments and dyes by scientists in the dye, food and wastewater treatment fields.

While chemically synthesized pigments are comprised of the purified compound (just the molecules of the pigment), dyers have a long history of finding ways to extract naturally occurring pigments from various plant materials to dye fabric. My kitchen is not a laboratory and my methods are crude, so anything I’m extracting in a jar in my kitchen or in a pot on the stove is going to be a mix of plant pigment molecules and other things that are soluble in alcohol and/or water. I also end up with very fine to coarse plant particles that don’t dissolve, which I can filter out, let settle to the bottom of a jar, or include (if they’re not scratchy!).

As soon as I can pull myself away from making soap I’m going to work on a reference table that I will post for anyone who might be interested. I got started down this road because of the color changes with chlorophyll and because I had no luck whatsoever getting my madder powder to infuse into oil. While some pigments, like the carotenoids in annatto seeds and paprika, seem to be readily soluble in oil, my madder powder hasn’t noticeably given up any color to the oil it has been sitting in for the last couple of weeks. Based on observations only, chlorophyll, which is a primary pigment in green plants and algae, seems to be at least somewhat oil soluble. But, unlike many of the carotenoids, it is a very unstable molecule. Soapers know that because the green colors fade or turn brown. For that reason, it’s probably better to use plant material ground into a very fine powder to get the green color. I also have an idea about trying to protect very finely ground plant material a bit from the ravages of lye by soaking it in a glycerin and alcohol mixture and then evaporating off the alcohol before using the glycerin infused powder in a recipe. Another experiment in the making! The primary pigment in Spirulina is phycocyanin, which I have not had a chance to research.

Indigo dye is especially challenging because it is insoluble. Dyers have to use a special process to make it “stick” to fabric. I just recently found a great article on using indigo in soapmaking. It’s by Kevin Dunn and is available on the WSP website, here. This is the key part as it pertains to using indigo in soap.
“Indigo is sold in two commercial varieties. The traditional one is a dark blue powder that is insoluble in both oil and water. It can be mixed with a little oil to make a slurry and then added to your oil as with any other solid soap colorant. The newer variety has been pre-treated with lye. While it is sometimes described as “soluble” or “pre-reduced,” it is actually neither of those in the strict chemical sense. It forms an opaque suspension in water (not a transparent solution), and may be added to your lye portion. Either variety may be used in soap, but they should be used sparingly to avoid staining hands, sinks, and countertops. One gram of indigo per kilogram of oil produces a dark grayish-blue color in cold process soap.”

I’ve had some success using indigo from Brambleberry (ETA: actually, mine in from Nuture), which I ended up mixing with oil because it really did not want to mix with water. I have not tried adding it to my lye water.

ETA: I just mixed some of the plant derived indigo powder I have with 91% alcohol and it readily formed a suspension. It’s too early to tell if the pigment will dissolve to form a solution.
 
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Thank you for sharing your great research. I am soaping vicariously through you (you don't mind do you?).
PS I use to use madder to dye my wool yarn when I was a weaver. It was one of my favorite colors to work with.
 
This will probably be much more than you wanted to know, but that’s the way it is for me once I get started on something I find interesting :)

The various kinds of plant pigments differ in their solubilities in different kinds of liquids, which can include “organic solvents,” alcohols, oil, water. They also vary in stability as a function of light, pH and other variables. It’s definitely complicated and many doctoral dissertations and scientific papers have been written on plant pigments and dyes by scientists in the dye, food and wastewater treatment fields.

While chemically synthesized pigments are comprised of the purified compound (just the molecules of the pigment), dyers have a long history of finding ways to extract naturally occurring pigments from various plant materials to dye fabric. My kitchen is not a laboratory and my methods are crude, so anything I’m extracting in a jar in my kitchen or in a pot on the stove is going to be a mix of plant pigment molecules and other things that are soluble in alcohol and/or water. I also end up with very fine to coarse plant particles that don’t dissolve, which I can filter out, let settle to the bottom of a jar, or include (if they’re not scratchy!).

As soon as I can pull myself away from making soap I’m going to work on a reference table that I will post for anyone who might be interested. I got started down this road because of the color changes with chlorophyll and because I had no luck whatsoever getting my madder powder to infuse into oil. While some pigments, like the carotenoids in annatto seeds and paprika, seem to be readily soluble in oil, my madder powder hasn’t noticeably given up any color to the oil it has been sitting in for the last couple of weeks. Based on observations only, chlorophyll, which is a primary pigment in green plants and algae, seems to be at least somewhat oil soluble. But, unlike many of the carotenoids, it is a very unstable molecule. Soapers know that because the green colors fade or turn brown. For that reason, it’s probably better to use plant material ground into a very fine powder to get the green color. I also have an idea about trying to protect very finely ground plant material a bit from the ravages of lye by soaking it in a glycerin and alcohol mixture and then evaporating off the alcohol before using the glycerin infused powder in a recipe. Another experiment in the making! The primary pigment in Spirulina is phycocyanin, which I have not had a chance to research.

Indigo dye is especially challenging because it is insoluble. Dyers have to use a special process to make it “stick” to fabric. I just recently found a great article on using indigo in soapmaking. It’s by Kevin Dunn and is available on the WSP website, here. This is the key part as it pertains to using indigo in soap.
“Indigo is sold in two commercial varieties. The traditional one is a dark blue powder that is insoluble in both oil and water. It can be mixed with a little oil to make a slurry and then added to your oil as with any other solid soap colorant. The newer variety has been pre-treated with lye. While it is sometimes described as “soluble” or “pre-reduced,” it is actually neither of those in the strict chemical sense. It forms an opaque suspension in water (not a transparent solution), and may be added to your lye portion. Either variety may be used in soap, but they should be used sparingly to avoid staining hands, sinks, and countertops. One gram of indigo per kilogram of oil produces a dark grayish-blue color in cold process soap.”

I’ve had some success using indigo from Brambleberry, which I ended up mixing with oil because it really did not want to mix with water. I have not tried adding it to my lye water.
Haha there is no such thing as too much information when it comes to soapmaking [emoji6] thanks for sharing your knowledge [emoji16]

I've actually had a really nice denim color from indigo added to the lye water. I'll try to check if I can find out which variety of indigo I have, because seeing the difference in results from indigo on this forum I think there's a lot of difference in types and quality of Indigo.
 
Haha there is no such thing as too much information when it comes to soapmaking [emoji6] thanks for sharing your knowledge [emoji16]

I've actually had a really nice denim color from indigo added to the lye water. I'll try to check if I can find out which variety of indigo I have, because seeing the difference in results from indigo on this forum I think there's a lot of difference in types and quality of Indigo.

:) Sounds good

I’ve been contemplating buying the pure indigo pigment from the supplier where I buy my fabric dyes. I dyed some fabric using the traditional shibori techniques for manipulating the fabric, but ended up using an indigo Procion dye because I didn’t want to get into messing around with the real indigo pigment. Now I’m trying to figure out how to use natural plant indigo in soap. Crazy! There’s more details on what I learned about the different plant sources of indigo, including some species names, above in case you missed it. The tests Amy Warden (GreatCakesSoapworks) did produced a range of colors, but she did not use every method with every kind of indigo she used.
 
Thank you for sharing your great research. I am soaping vicariously through you (you don't mind do you?).
PS I use to use madder to dye my wool yarn when I was a weaver. It was one of my favorite colors to work with.

Soap on and let us know how it goes! :)

I’ve always wanted to try dyeing with plant materials but felt like I should have wool or silk rather than cotton. Never quite got there, but one of these days I will be retired with lots of time to try even more new things!
 
I've soaped, and posted, three different kinds of indigo but not extensively.

The powder straight off the plant will not give blue. It'll be a caramel sorta color.. One indigo gives more of a grey blue, and one gives blue. Unless that's not what you meant? Haha

I have a feeling that anything that's made and sold for soaping isn't "pure" in the sense that it comes straight from the plant, coz I've had similar experiences with ratanjot (similar to Alkanet), madder root and even moringa and turmeric. Maybe there's a process that the "raw" material I have hasn't undergone or mine lacks whatever additives the soaping stuff has?

I've never gotten a similar color to what others have gotten (at least from what I've seen here and online lol) and all of my powders and roots came from either the supermarket or a spice vendor, except for the blue indigo. I dried n powdered my own moringa leaves.. the turmeric we use regularly in cooking comes from a Pakistani grocery.. my madder came in both root form and coarse powder, same with my ratanjot. Both indigo powders I have were gifted, one from a soaper, and the green indigo is also from a spice shop.
 
Soap on and let us know how it goes! :)

I’ve always wanted to try dyeing with plant materials but felt like I should have wool or silk rather than cotton. Never quite got there, but one of these days I will be retired with lots of time to try even more new things!
Cotton is a harder fiber to dye. Wool and silk fibers open up and receive the dye very well. Continue your investigation, and hopefully you will share your findings with us. Good work!
 
Looked up the info on my indigo.. on the package it just sais 'indigo'. On the suppliers website it's specified as 'Indicum naturalis, Indigofera tinctori' and 'premium quality from El Salvador', so not really sure if that info is helpful
 
Looked up the info on my indigo.. on the package it just sais 'indigo'. On the suppliers website it's specified as 'Indicum naturalis, Indigofera tinctori' and 'premium quality from El Salvador', so not really sure if that info is helpful

Oops, the indigo info I posted is in this thread and mostly in the first post, where you can also see the color I achieved. :) I think I. tinctori is the traditional indigo plant, but indigo is made by many different plant species and some marine snails as well.
 
Yes, I've seen that thread, I love that soap!! I meant it might not be helpful in the sense that I'm not sure if it was the non-soluble or the pre-reduced version..
 
Yes, I've seen that thread, I love that soap!! I meant it might not be helpful in the sense that I'm not sure if it was the non-soluble or the pre-reduced version..

Thank you szaza :). The info on non-soluble vs. pre-reduced seems to be hard to come by unless you buy the indigo from a dye supplier. I think dyers are highly educated on the plant materials they are using. I think some soapmakers are, too, but it seems that some of the most accomplished with using plant colorants have retired from soaping.
 
Another test with madder, as well as the indigo I bought from Nuture. I included the previous madder test soap for color comparison. For this test, I added a little boiling distilled water to the indigo and madder powders at around 7 am, mixed the indigo as best I could and then let them sit until 6 pm when I made the soap. I then added the additional water I needed for the lye. I strained the cooled lye water through a piece of cotton interlock material, which I used to line in a small sieve. This ensured that no chunks of anything got through, but was not enough to keep some very fine particles of the madder powder from making it into the middle soap. The pink from the madder in this test is a little warmer than the pink that I achieved using the alcohol tincture (the layer just below the white one in the soap on the right). Based on everything I’ve read, that happens because the boiling water method pulls some brown pigments out of the madder. The tincture method keeps the temperature low, which should theoretically help to retain the purer red (alizarin) pigment.

For now, it looks like both the tea method (boiling water/lye water extraction) and the tincture method (alcohol/water extraction) produce great pinks. I’m also super happy to have figured out the concentration for a mid saturation color with the indigo powder I have.

1EC7CEA7-3BA8-4AC2-86A3-1112BE349838.jpeg
 
That's a very pretty blue you got there!! Really like the difference in shades of pink between the 2 madders as well[emoji6] it's cool that you got a warmer and a brighter shade! Now you can choose which one you want in a particular soap[emoji106]
 
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