This all started out with a leather bag I was making. After making the pattern I thought it would be nice to add some color to it for a change. Of course, I had no color available, and getting some would involve ordering and waiting a week for delivery. I didn't have the patience for that, so my next thought was; "hey, people colored leather and fabric for millennia before industrial production and internet ordering was an option. Lets see what I can produce myself."
Luckily plants are full of different color pigments in leaves, roots and flowers. All we have to do is extract them
At this point I have extracted red from Beetroot, Yellow from Dandelions and green from grass. I'll update this instructable with more pigments as I try them out.
Step 1: Equipment
Making color extracts from plants doesn't require much in terms of equipment.
- Glass or steel bowl. Plastic containers work fine, but can be permanently stained by the color pigments.
- Blender, grater or mortar.
- Cloth to filter extracts
- Water or ethanol as solvents.
- Airtight container for storage.
Step 2: Solvents
Different color pigments require different solvents, but in general they are soluble in water or in oils.
Most plant color pigments are water soluble, but the chlorophylls are hydrophobic (water hating) and dissolve best in a hydrophobic solvent. Petroleum derived solvents (hydrocarbons) or acetone work best, but are obviously not food safe.
For most plant pigments ethanol is a great solvent. If you use 60-70% ethanol, you will be able to dissolve both hydrophobic and hydrophilic (water loving) pigments. Ethanol is sometimes classified as a soluble hydrocarbon. I won't go further into the chemistry, but the gist of it is that ethanol can function as a solvent for both hydrophobic and hydrophilic substances. Handy right?
Ethanol is also nice to work with in terms of not being very toxic. As an added benefit it is food safe and serves as a preservative so you can keep the color extract for a long time.
Step 3: Dandelion Yellow
The first step is to pick a bunch of Dandelions.
The next step is to pick the flowers apart so you are only left with the orange petals. If you don't remove the green bits, you are going to extract chlorophyll as well as the orange flavonoids that we are looking for.
Once you have all the petals you want, pour on some ethanol. You don't have to completely cover the petals, just make them moist. Use a spoon to mash the petals with the ethanol and let it sit for an hour or so. If you use too much ethanol the color of the extract will be weak, so try to use as little as possible and still keep things wet.
Step 5: Filter
Place a piece of fabric in a bowl and poor the soaked petals over it. Close the fabric and squeeze out as much of the liquid as you can.
Step 6: Bottle and Use
Pour the finished color extract into a airtight container for storage. Natural color pigments degrade faster in light than most artificial pigments, so storing the color extracts in a dark place will make them last longer.
Step 7: Beetroot Red
Beetroots are extremely colorful, and a great source for red pigments.
Step 8: Grate, Soak and Filter
Grate the beetroot and soak it in ethanol for about an hour. The red pigments from beetroot dissolve very easily in water, so if you are using the extract right away and don't plan on storing it, there is no need to use ethanol.
Poor the beetroot into a cloth and wring out all the liquid.
You now have a beautiful red color extract. It hardly has any taste at all, so you can safely use it in different foods like cake frosting.
Step 9: Chlorophyll Green
All green plants have chlorophyll, but as there are several types of chlorophylls the color you get may vary. Grass gives a nice and intense green color, so that is what I used for this extraction.
Grass has a fairly strong smell, so this might not be the best extract to use in foods. To both flavor and color food, you can use herbs like Mint and Basil for this as well.
Step 10: Mash, Soak and Strain
Simply leaving the grass in ethanol doesn't give you much color. You need to get a bit violent with the grass first to break the leaves apart. I put my grass in a blender to mash it up a bit.
After mashing the grass I put inn some ethanol and let it sit for about an hour. You don't need to add huge amounts of ethanol. I just wet the grass mush with it and stir it with a spoon now and then. After an hour or so most of the color that is going to be dissolved is dissolved. You can leave it longer if you like, but the intensity is not going to change much. The next step is to strain the mush through a piece of cloth, and voila, you have your green color extract.
Step 11: Natural Beauty
After only a couple of hours we have produced several beautiful color extracts than can be used in a range of projects only limited by imagination.
Step 12: Use
My original intention with this extract was to color leather, and it works great for that. The color is fairly weak on leather, so you have to build up intensity by applying several coats. Ethanol is an advantage here, as it evaporates quickly, so you don't have to wait long between each application. Colors go lighter when they dry completely, so you might want to apply more after a couple of hours when you see the dry intensity.
I have no experience with using these extracts on fabric. There are several instructables out there on dyeing fabric, so check them out if you want to give it a try. Remember that when coloring fabric, you will need a mordant to fix the color.
All these extracts are food safe. Be aware that the extract will retain some aroma from the plant you used, so adding to much could give your dish a hint of freshly mowed lawn or flowering Dandelions. This can be used to your advantage by making color extracts from herbs that add to the flavor of the dish as well as the color.
I'd be happy to hear about your experiences with this kind of color extracts in the comments.