Snuggled Eggs, or Miso-fermented Egg Yolk

The end result of this ferment is a creamy, rich and delicious ball of goodness.  And with a texture and flavor much more reminiscent of a soft stinky cheese than of egg yolk.  I first read of this process in The Book of Miso, by William Shurtleff & Akiko Aoyagi.


It’s fairly straight forward: bury egg yolks in miso, wait, recover yolk, and enjoy.


I ferment a dozen or two at a time, and my method was inspired by the playing with fire & water food blog [].


Materials: fermenting vessel, miso paste, soft boiled or raw egg yolks, and cheese cloth.  These are layered in a crock in a sandwich-like fashion. I start with a 1-2” layer of miso, and then place a single layer of cheese cloth on top.  I use a handle of a wooden spoon (it has a very bulbous end) and push divots into the miso the size of the yolks, pressing the cheese cloth into the miso as I go.  Next, I carefully set the yolks into the divots, and cover with another layer of cheese cloth. I then cover it all with another layer of miso paste. I repeat this process until I run out of yolks, or room in the crock.

An important detail is to keep the corners of the cheese cloth visible on top of the layer of what is on top of it , so that you can lift out what is on top of it, either a layer of miso, or of yolks, easily and cleanly. The whole purpose of the cheese cloth is to be able to recover the yolks as whole discrete balls, and not as mushy smashed blobs full of miso bits. And it works really slick, too.  Here are some photographs.


Putting divots into the miso on top of a layer of cheese cloth.


Adding a raw yolk.


Five soft boiled yolks wrapped in cheese cloth and ready to be covered in miso. I’ve pulled in the corners of the cheese cloth so they will be revealed after I remove the layer of miso that will sit on top of them.


Adding a top layer of cheese cloth and miso.


These yolks are ready to harvest.  I’ve removed the top layer of miso (bowl on left) and exposed the  yolks beneath.


Here is the layer of yolks removed inside their own cheese cloth, and a solo yolk about to be tied for drying.


These yolks have been tied in cheese cloth and draped over a beer bottle. They’ll stand in the fridge for a couple weeks and dry out to a crumbly or even a grate-able texture.


These yolks went into the smoker still inside their cheese cloth.  They are amazingly delicious!


My first batch of yolks I let ferment 6 months.  One week seemed way too short to me.  Having done both, the one-week yolks achieve a very sour taste, but lack the complex flavors of the miso from a longer ferment.  Both are very good. When I ferment a dozen or more, I use a crock and pack the top with a plate and weight, just as though I were making miso.  I’ve made one-week yolks only in a small jar, and it sits on the counter in the kitchen until ready.  I think either could go in the fridge for the ferment, though it might take longer.  Which ever method you use, remember to leave head space in the top of the vessel for some CO2 expansion, and liquid/tamari collection.

My favorite way to enjoy the yolks is as a spread on good bread or crackers.  They are also great blended in salad dressing, spread on top of poached eggs (with a little tekka miso sprinkled over), or tossed with fresh noodles or pasta.  They are also a fun food for a potluck, as they seem to push the limits of the culinary frontier, and the flavor of this ferment nearly always wins over a hesitant doubter.



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16 thoughts on “Snuggled Eggs, or Miso-fermented Egg Yolk

  1. Which egg did you prefer the taste of–the raw one or the soft-boiled? I am wondering if there is more health benefits with the raw yolk. Does anyone know the answer?

    • Both taste similar if not identical to me. However, my raw egg yolks generally break during the ferment (perhaps the weight/pressure of the miso on top is too much) so I end up with a layer or blobs of fermented yolk mixed with the miso paste, rather than discrete orbs of yummy ferment. The whole yolks are great for presentation as an creamy spread on an hors d’œuvre, or for drying and grating or even smoking. But both are very tasty. I do not know if there are differing health benefits between them.

    • I have no concerns about salmonella. I am rarely concerned about food-borne illness when I eat my fermented foods. I trust my nose, and I trust the ferment process. I’m way more concerned about the flavor. My interest in fermenting foods is fueled by the fantastic flavors.

      Check out this excerpt from an article in Journal of Applied Microbology: Probiotics and Their Fermented Food Products are Beneficial for Health: Lactic acid bacteria are known to release various enzymes and vitamins into the intestinal lumen. These exert synergistic effects on digestion, alleviating symptoms of intestinal malabsorption, and produced lactic acid, which lowers the pH of the intestinal content and helps to inhibit the development of invasive pathogens such as Salmonella spp. or strains of E. coli (Mallett et al. 1989; Mack et al. 1999). Volume 100, Issue 6, pages 1171–1185, June 2006.

    • In my experience there is little difference. And my experience is using older and more salty miso pastes to ferment to the yolks. I’ve never used a sweet miso, and I ferment the yolks for months rather than weeks. I suspect if you harvest the yolks sooner (days or a couple weeks), the miso flavor carries through and then it would make more of a difference. I find the longer-fermented yolks considerably more sour from the lacto-ferment, which dominates the flavor on my palette.

  2. This is an email I received from Eli Brown:

    Inspired by your recent post, I tried the miso fermented egg yolks. Today I harvested them after two months in a batch of home made azuki bean miso and they were startlingly good. Like a marriage of salmon roe and a salty brie. Even my sweetheart– who was ooked out by the whole thing, tasted and liked it. Strong flavors– very rich and creamy but not overpowering.

    It was so unique and such a delicacy that I felt it deserved a name..something more compelling and worthy of the flavor than simply miso-fermented eggs yolks. Consider the status upgrade those black eggs got when they were designated “Hundred year eggs” rather than “eggs we buried in the dirt.” Also, the resultant food seemed as distant from egg yolk as cheese is from milk.

    Maybe “Savis” from the Latin for delicious…
    or maybe “Fairy eggs”

    It occurred to me that if I weren’t making my own miso the whole project would be much too expensive–glad to have so much on hand.
    One thing I would do differently: I set them into the miso raw and lost a lot to leakage and smearage. I would definitely soft-boil them next time.

    Eli Brown

  3. These eggs look wonderful and I would love to try this as I usually have a lot of miso on hand. Miso is undoubtedly one of the most wonderful foods in the world. It can be taken anywhere and lasts indefinitely in the fridge. I use hatcho miso to make “oat milk”. I cook the oats, let them cool and stir in 1 to 2 tablespoons of miso, let it sit overnight, strain, refrigerate, add sweetener and drink. This drink provides me with abundant energy and I am sure there are many benefits from this food.

  4. Great article.. Really want to try, but two questions: as i usually just buy miso, how much do you think it would take? Second, how do you soft boil just yolks? Was thinking in one of those poach pods?

    • I boil the eggs whole, then peel them. A poach pod would certainly work, too. What ever method you use to get the yolk to the soft stage, avoid breaking the membrane if you want a whole yolk as the finished product. Otherwise, you can swirl the broken yolks into the miso using a spoon, and it will ferment just as well. I think you could easily ferment 4 yolks in a pint container. Just make certain the yolks are completely covered through the process.

  5. The references to lactic acid bacteria confuse me. Miso fermentation is koji based and involves fermenting proteins, how does LAB play a role then?

    • You are correct that the enzymes from the koji chop up the proteins in the legume substrate, yet there is also a LAB fermentation going on in tandem with the activity of the koji. The mechanical process of making miso (steaming the koji rice and inoculating it wtih a single strand of mold; boiling the legume substrate; kills any bacteria that might otherwise contribute to the LAB process. Hence, a new batch of miso is back-sloshed with a ‘live’ miso culture, to inoculate it with LAB before packing it into a fermenting vessel.[Technically, I’m uncertain that the koji does any actual ‘fermenting,’ it’s all about the bacteria.]

  6. I made something similar with Ssamjang and koji instead of miso. Fermented for 40 days and I got a beautiful creamy yolk. Then I smoked it. The flavor is amazing

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