After this week, I will have processed 30 gallons (dry weight) of black walnuts into ink. After doing this much ink (by far the most I've ever processed in such a short period of time), I've learned to streamline the process somewhat. I thought I'd write it out in steps, with photos.
Black Walnut Tree
Cooked-Down Black Walnut Ink 2013
Playtex Dishwashing Gloves
Non-Reactive Cooking Pot (I use a large canning pot)
Paper & Dip Pen (to make writing samples with)
Buckets or Bowls
Fine-Mesh Paint Strainer
Cloth for Filtering
Measuring Cups or Containers
Steel Wool (optional)
Black Walnut Husks
100-Proof Vodka (optional)
Gum Arabic (optional)
Glass or Nalgene Bottles
Badger Ink Mixer (optional-- but very useful)
1. Wearing heavy-duty dishwashing gloves (like Playtex), de-husk the black walnuts. It is the fleshy outer part you want for ink, and not the hard shell or nut. Most will have Black Walnut Maggots feeding within the husk. Brush these aside (chickens love them!) Put the husks into a non-reactive pot and cover with distilled water (I admit to using my well water, which has a bit of iron in it. I would not use chlorinated tap water.) If you need to, you can let this soak overnight or even considerably longer, until you’re ready to cook it down.
Black Walnut Maggots
First Steaming Stage
2. Bring the husks and water to a boil. Watch carefully, as this boils over very easily and makes a huge mess! Once it’s boiling, drop the heat down to just below a simmer-- with no bubbling in the pot, but with steam coming off the surface. Put a lid on. Cook it down for several hours to make an extract. Stir it from time to time. Make some writing samples. Continue to cook it down until it’s dark and doesn’t seem to darken any further. Be patient during the two cooking stages, especially if making a large quantity; don’t rush and scorch the extract. For this step, I tend to cook this from the time I wake up until I go to bed, then turn the heat off (a smaller quantity would require much less time).
3. Allow to cool, even overnight. Then strain and squeeze through a nylon fine-mesh paint strainer. This is to remove the big chunks and not the smaller particles (there will be a final filtering through cloth later.) I put one or two handfuls of husks in the strainer at a time– just enough for my hands to manage to squeeze easily. Try to squeeze out as much of the liquid from the solids as possible. Discard the solids.
Wringing the Fine-Mesh Paint Strainer
Second Steaming Stage
4. Return the liquid extract to the non-reactive pot. Carefully bring to a boil (again, watch to make sure it doesn’t boil over). Drop the heat down to just below a simmer so that there is no bubbling, but only with steam rising off the top. Leave the lid off this time. Allow it to reduce down, stirring from time to time. This cooking stage requires less than half the amount of time than the first cooking stage. A film may appear on the surface (this is the sugars carmelizing). Just stir it back in. Make writing samples periodically (every half hour or so at first, then as it begins to darken, make a sample every 15 minutes). Don't be surprised if, at first, the ink looks paler than the writing sample was from the day before. Just keep stirring and reducing it down and it will get darker again. Keep reducing the ink down to the color strength that you like. If desired, add some clean shiny steel wool to impart some iron to help darken the ink to a blackish-brown sepia color (optional.). Keep in mind, if you will be using alcohol as a preservative later, that it will dilute the strength of the color a little, so take this into account as you judge the strength of the color. There will come a point where it just won’t darken any more, so be careful not to steam all your ink away in trying to get it darker. Stir the ink well before each time you make a writing sample– this will evenly distribute the pigment so that you will get a more accurate color sample.
Notice the Steam Rising Above the Pot -- and No Bubbles in the Pot
Dropping the Steam Wool In
5. Allow the ink to cool. Don your heavy-duty dishwashing gloves again. Strain again through cheesecloth (I like those flour sack dish towels for this), to remove any remaining particles that might have slipped through the mesh. Wring the cheesecloth to get every last drop of ink that you can. Calculate how many ounces of ink you have.
Note: These cloths as well as the paint strainers can be bleached in the washing machine and used again. I use them only for ink-making.
Finishing It Up
6. If desired, add 10% alcohol by volume for a preservative (I use 100-proof vodka), stirring well. Black walnut is naturally anti-fungal, so if you ( A ) keep your bottles cool and ( B ) transfer the ink to smaller bottles as you use it up to prevent air exposure, AND ( C ) if you use whole cloves as a preservative, you can avoid mold even without using alcohol. But if you want the added protection, use the following excellent formula by Paddler to calculate how much you will need.
AX = B(C+X)
A = alcohol proof divided by 200. This is the alcohol concentration of your booze expressed as a decimal.
B = the alcohol concentration, expressed as a decimal, in your finished ink.
C = the volume, in ml, of raw ink you are starting with.
X = the volume, in ml, of booze you must add to the raw ink.
Solve for X.
7. If desired, add 1 part powdered gum arabic to 30 parts ink, though it’s not necessary (it can make the ink a little less runny, but it does decrease water resistence. Don’t use it if you desire a waterproof ink). Stir well. The lumps will dissolve overnight. Stir again. Make some writing samples.
8. If your ink has been sitting for awhile prior to bottling, it can be helpful to pour the ink from one container to another beforehand a few times, to make sure the pigment is evenly distributed throughout before you bottle it. Be sure to scrape the bottom of the container, too (some of the darkest pigment tends to settle at the bottom and you want this stirred back in evenly before bottling to retain the color strength). Bottle in sterile glass or Nalgene bottles, adding several whole cloves per bottle (this is for a preservative-- cloves have phenol in them). Label with the date. Use this ink with dip pens only, preferably gold-plated or stainless steel nibs (the acidic nature of this ink will rapidly tarnish most other metals). Glass pens and feather quills are also excellent with this ink. Try it on banana paper with a glass dip pen!
9. This ink tends to drop a thick pigmented sludge on the bottom of the bottle as it sits. It’s too thick to shake back in, but you can stir it back in, scraping the bottom with a popsicle stick, or use a hand-held battery-powered Badger Ink Mixer (which retails for about $13 and fits inside bottles up to 4 ounces in size). If you don’t stir this pigment back in before writing, the ink will be thin. I always stir my black walnut ink before using it. Always.
10. Your ink will keep for many years, especially if you minimize oxygen inside the bottle (transfer to smaller bottles as you use it up). This ink is permanent (fadeproof), as well as waterproof (if gum arabic is not used). Water resistence increases the longer it dries on the page.
• I processed one 5-gallon paint bucket full of whole black walnuts at a time (took 2 ½ hours to de-husk each batch).
• The husks (and water to cover) filled a large canning pot to the very top.
• I reduced the husks down until I had 58 ounces of extract.
• I added 14 ½ ounces of 100-proof vodka and 2.41 ounces of powdered gum arabic
• Total time taken per batch = 4 days (2 ½ hours spread over 2 days for de-husking/soaking; and 2 more days of steaming the extract down)
• Total yield of ink = approximately 75 ounces of finished ink. (Other 5-gallon batches I processed yielded as much as 128 ounces of finished ink... you just have to be careful not to steam away your ink in that final steaming stage. Keep a close eye on it towards the end and don’t let yourself get distracted, or you’ll discover when you return to the pot that there isn’t much ink left!)
Edited by fiberdrunk, 17 October 2013 - 04:13.