Black Bean Dye: Dyeing from the Kitchen

Black beans were the dye I was most excited to try recently. When researching what dyes I could source from the grocery store, I was faced with images of beautiful blues and teals, I couldn’t believe it! Blues that don’t require a fermented vat! Now I just had to test the dye for myself. 

I looked to a classmate of mine who worked with black beans to create blue dye, so I’m taking cues from her project, just on a smaller scale. 

From what I have seen, we will start with dried black beans. I assume the amount you use will be based on the weight of your fibres, but having not found a precise recipe I will just be winging it. 

The basic steps to follow are: 

  • Weigh your black beans to keep a log of your process so that you can recreate your results.
  • Soak your black beans in water for 12 hours (less water= more concentrated)
  • Strain the dye out after 12 hours, refill your container with water and soak the beans for another 12 hours.
  • Strain this second batch of dye into the first.
  • If you do not have enough to cover your fibres you can add more water, but this will dilute the dye. 
  • This will be a cool dyebath, so at this point you will not need to heat your dye bath before adding your fibres.
  • Add your mordanted and pre-soaked fibres to your dye bath.
  • Allow your fibres to soak at least overnight, stirring occasionally. You can leave them in the dyebath until you’re happy with the colour. 

Keep reading to see my own experiment and the results I got! 

Fibres I used: Mercerized Cotton; Silk Habotai; 100% Wool

Paper I used: Canson Watercolour 140lb cold pressed; Canson Mix Media 98lb

For the fibres I did 3 tests per colour. I had a series of unmordanted samples, a series of alum mordanted samples, and a series of soy mordanted samples. 

Alum mordant: Follow this link for detailed instructions. 
I mordanted silk habotai, wool and cotton in alum. I used a 17% solution and mordanted them using the stovetop method. 

Soy Mordant: I only mordanted my cotton in soy, as the other fibres are protein fibres already. Link to instructions. 
I soaked my fibres overnight in the soy milk, and did the “quick dip” step 3 additional times over 2 days. I then let the cotton “cure” for 3 days before dyeing. 

After I completed my mordanting I was ready to move onto dyeing the fibres! But first I had to figure out how many black beans to use.
I have read a variety of dye recipes that all seemed to list different quantities, but I knew I wanted a darker colour, so I opted to use at least double the weight of my dry weight of goods (DWoG). I weighed out 112g of dry black beans and these are what I soaked in water to create my cool dye bath.

I soaked the black beans in water for 12 hours in a 750ml mason jar. After 12 hours I  strained the liquid ( the dye) out in a bowl and refilled the mason jar with water. I soaked the beans for another 12 hours and then strained this second batch of dye into the first. This bowl of dye became my dye bath. I pre-wetted my fibres and added them to this dye bath. I let them soak in the dye for 21 hours, stirring and flipping them occasionally to make sure all areas of the fibre samples were exposed to the dye. I then rinsed them with tap water and hung them to dry.

I proceeded to use my same black bean bath to dye some paper! I used Canson Watercolour 140lb cold pressed and Canson Mix Media 98lb papers, both of which are affordable, versatile and accessible.
I first painted on my papers with soy milk. This will cause the dye to attach to the protein in the soy milk to achieve a different colour. Painting with soy milk is a easy way to create designs and patterns! You can also follow the same steps as you would with fibres and mordant your paper with soy milk as well, just don’t put it in the washing machine.
Once the soy milk was dry I submerged each paper in the black bean dye one at a time, waiting for each previous sheet to be completely wet before adding another sheet. I soaked the paper for roughly an hour before hanging them to dry. 


From left to right: Canson Mix Media 98lb, Canson Watercolour 140lb cold pressed, Alum Mordant, No Mordant, Soy Milk Mordant


After completing the initial dyeing of my samples, I further divided these samples into smaller groups. These groups were so that I could “post-modify” my samples; meaning change their pH and therefore their colour! My three groups were: no post-mordant, acidic post-mordant and basic post-mordant.
Acidic post-mordant:

  • Pre-wetted the fibres
  • Mixed white vinegar and cold water at a 1:1 ratio
  • Submerged the fibres in the vinegar solution for 5 minutes
  • Removed the fibres, rinsed under the tap
  • Further rinsed fibres in cold water with a few drops of synthrapol
  • Hung fibres to air dry
  • I used the same vinegar solution to modify my paper samples.


From left to right: Canson Mix Media 98lb, Canson Watercolour 140lb cold pressed, Alum Mordant, No Mordant, Soy Milk Mordant


Basic post-mordant:

  • Pre-wetted the fibres in cold water
  • Mixed baking soda and hot water to create a basic solution, I let this cool down to room temperature before submerging my fibres
  • Use 2 tsp baking soda per 1 cup of water, I used 8 tsp of baking soda in 4 cups of water
  • Submerged the fibres in the basic solution for 5 minutes
  • Removed the fibres, rinsed under the tap
  • Further rinsed fibres in tepid water with a few drops of synthrapol
  • Hung fibres to air dry
  • I used the same baking soda solution to modify my paper samples.


From left to right: Canson Mix Media 98lb, Canson Watercolour 140lb cold pressed, Alum Mordant, No Mordant, Soy Milk Mordant

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