Adventures in Ethics and Science

Tomorrow being Easter, a day on which there is some expectation that there will eggs for which to hunt in the backyard (weather permitting), the Free-Ride offspring and I decorated some eggs. We had an old package of oil-based dyes to make “swirled” eggs (the basic idea being that you float drops of the dye on top of cold water, then lowers the egg into the patches of dye, creating a sort of Jackson Pollock swirly effect on the shell).

But for the next dozen eggs, we thought we’d try something a little different. So we gathered some plant materials we thought might have pigments that we could use to create homemade dyes.

Here’s our basic procedure:


Put the plant material in a small saucepan. Cover with water and bring to a boil. Add eggs to be dyed, reduce to simmer, and cook for 20 minutes.

A couple notes:

This cooking time assumes raw eggs in the shell, with an aim to create hard boiled eggs with colored shells. If you are working with blown eggs (i.e., egg shells whose innards have been blown out), you don’t actually need to cook the shells you’re dyeing, and you can leave the egg shells in the dye for as long as you want to develop a darker color.

If you are using plant material that is not known to be edible, use only blown eggs. You don’t want something potentially toxic seeping into your hard boiled eggs.

(What can you do with the innards blown out of the eggshells? We’re using them to make matzoh balls.)

What we tried:

Skins from yellow onions:

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This made a very deep reddish-brown. In the event that you ever need to disguise white eggs as brown eggs, an onion skin dye could do a passable job.

Red and pink stems from Rainbow Chard:

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Sadly, not much happened. The eggs’ boiling water was a pale pink, but the egg shells still look white. (I’ve posed the two I dyed with an undyed egg. There’s a difference, but it’s disappointingly subtle.)

Pickled beet pickling liquid:

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If you have a fresh beet on hand, you can slice it up into the sauce pan, cover with water, and boil to create a dye. But we had a container of pickled beets in the fridge, so we just stole some of that liquid and soaked blown eggs in it for awhile.

Pretty!

Petals from dark purple tulips:

For this one, because we are not habitual tulip eaters, we only used blown eggs.

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The color that developed was a dark blue with maybe a hint of a greenish cast to it.

Red cabbage:

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Yes, the very same kind of red cabbage you can use to make your own indicator. A few things are worth mentioning here. First, neither raw eggs nor blown eggs developed much in the way of color after 20 minutes of simmering. So we took the cabbage water off the heat and kept soaking. Second, the egg shells with egg innards still inside grabbed the pigment better than the blown eggs. Third, even though the cabbage water itself has a definite purple color to it, the color that developed on the shells of the hard boiled eggs was blue.

Any guesses as to what might explain that last detail? Anyone?

Some other plant materials rumored to give good results are walnut shells and coffee grounds. I’m betting grape skins from dark purple grapes might yield interesting results, too.

Comments

  1. #1 Coturnix
    April 11, 2009

    Lovely. The onions skin dyeing is the way to make Shallet Eggs for Passover – but they are simmered in it (as well as salt, pepper and a little vinegar) for something like 24 hours straight. Thus, it is not just the shell that gets brown – white and yolk also get brown and very, very tasty!

  2. #2 Joshua Zelinsky
    April 11, 2009

    I’ve seen cholent recipes that involve heavy use of beans and have eggs put in at the top which are cooked with the entire thing and then removed when hard boiled. In some cases they take on a dark brownish color (I assume from the beans) but I don’t know any of those recipes myself so I can’t give much in the way of detail.

    Regarding the difference in color I’m presuming it has something to do with the pH and the fact that red cabbage juice will normally function as an indicator. The surface has a lot of calcium so if any of that is interacting with the water you should get it to act like it has a high pH. Is there enough calcium in the shell to do that or am I totally off base?

  3. #3 wolf
    April 12, 2009

    I’m guessing it’s got something to do with the calcium on the shell too – perhaps there’s a surface reaction that occurs when you boil the shell, which gives it a thin Ca(OH)2 coating.

    Tea leaves would give quite a dark colour to the shell. Yummy too!

  4. #4 Joseph j7uy5
    April 12, 2009

    We used to make Ukrainian eggs. These are made by using a stylus that can draw fine lines with melted beeswax. The eggs are dyed, and lines are drawn. Then dyed again, then the lines removed with dry cleaning fluid. This builds up layers of color, giving a stained-glass look.

    It was loads of fun. Now, however, I wonder what that 1,1,1-trichloroethane did to us.

    Navajo used pine bark, sunflowers, black walnut shells, and juniper, in addition to the things you mentioned. They were dying yarn, though. I should think it would work with eggs.

  5. #5 Larry Ayers
    April 12, 2009

    Great post, Janet! I wish I’d documented the years when my kids were young as as well as you have yours!

  6. #6 Abel Pharmboy
    April 12, 2009

    Janet, you have this natural products pharmacologist tingling with delight. I wish we had done that yesterday instead of using that boring PAAS kit.

    Yes, Joshua, if you go back to Janet’s earlier pH indicator post, you’ll see that the basic pH of eggs (and the Ca in the eggshells) causes the red anthocyanin to turn blue.

    Dr Free-Ride: Super Genius, Super Mom!

  7. #7 Jennifer
    April 13, 2009

    The trick to onion skins is to wrap the eggs in a cloth, surrounded by skins. Then you get fabulous variation in pattern and color. If you manage to save a bunch of red onion skins over the year, it is worth doing those in a separate pot.

    Coffee is also a great dye, as is a licorice root decoction and diluted currant-blueberry jam. Chlorella doesn’t work but I’ve read that spinach is great for green.

  8. #8 Luna_the_cat
    April 14, 2009

    Don’t neglect spices! You can get a lovely yellow from turmeric (or chamomile, or of course saffron), and paprika or chilli powder turns out orange…and to me, tasty.

    Try Celestial Seasonings Red Zinger tea for red eggs, or hibiscus tea for a really nice violet. Or violets. You can cook violets down for their colour. And cooking eggs with peeled dandelion root also gives you red.

    Yes, spinach works for green. As does, oddly, marigold petals. Or rosemary.

    It does help the colours if you cook them with a teaspoon to a tablespoon of white vinegar.

  9. #9 Cordelia
    April 14, 2009

    Why are the cabbage eggs shiny? (I’m not being snarky, although I know short questions can read that way; I really want to know.)