Saving your own Koji Spores

fermentation, mold

One time a million years ago was the only time we ever purchased koji spores. As with our gardens and farms where the priority of seed saving carries us from one season to the next, hopefully adapting to the unique character of our land and weather, so it also made sense to foster that seed saving mentality to our spores and cultures.

Saving koji spores is as easy as growing koji because, well, they are the same thing. If you’re a grower of koji already then you can perhaps find the permission to follow through with your spore saving here.

To save koji spores we are simply looking for mature koji. I usually shoot for mature rather than over-mature as I feel better about a cleaner population. Many times I won’t even attempt to over-shoot my koji incubation, instead proceed with the process as usual, and put some aside for “seed” and it always ends up working fine. When growing your koji hopefully you can notice a bit of powder on the surface as that’s sign enough that’s ready. The bits I save from a batch are usually the best looking parts, with no discoloration or peculiarities. Those pieces are allowed to air-dry fully then they are bagged and stored in the freezer until the next time I make a batch of koji. To use them I’ll hand grind just before sprinkling on my newly cooked grain. And like any other culture, a little is saved again to keep it all going.

Making a Miso Tradition

fermentation, Homegrown Grains, mold

The winter solstice has for myself become the day for annual miso-making traditions. It’s after most of the hardy holdout plants are finally delt a frosty blow, and grains and beans from the year are (hopefully) dried and threshed and stored away. Miso was introduced to me with an aura of magic- one of the first ferments I interacted with and so carries the same wild mystic held by the woods on a full moon’ed night as when I met it then. It’s retained its magic over the years, and that seems like a feeling worth fostering in anyway possible.

Sticking to annual miso-making means there are countless jars who present like vintages of wine marking out the years. The differences between the young and old ones are tremendous. It’s something that if you make, I highly recommend then hiding it from yourself for a couple of years. Just the other day I unearthed a crock that has been living on my porch for two years. It’s made of our homegrown marfax beans and danko rye. The location was an accident, probably nowhere anyone would recommend. I never really covered it or protected it from weather. The ceramic weights were covered thickly in fly pupal cases. After pulling them out and scraping off the top layer it was gorgeous miso with a fruity alcoholic smell the rest of the way down. It was scooped into a series of peanut butter jars to continue aging in the basement somewhere I already can’t recall.

Here’s how we’ve made miso, generally this same way every time, and may you find a way that works for you and becomes your own:

Preparing the Koji

First you’ll need some koji spores. Most people love GEM Cultures. If you’re really impressive you can go outside and find some growing out there somewhere. Either way add your cultures to a cooked starchy grain, mix, and incubate in mid-80 degree temps until your mold spores have colonized the grain. Since we mostly make our misos from homegrown grains like wheat or rye, it takes some extra cooking soften the grain enough to receive the mold. In other cases like with rice, a kernel that is just-cooked through and holds its shape is best. When your grain is cooked spread it out to let dry some and cool to about a mid-80’s temp and inoculate right away by spreading and mixing your spores in. The finished koji grain can be dried and saved or used immediately.

Preparing the beans

Unlike when making tempeh– who does better with beans cooked juuuust right (not over cooked), miso has no such need. Cook your beans fully after a nice overnight soak by boiling them, but in this cook no salt is needed.

Strain and let the beans cool. Often times I’ll let them sit out until the next day because life is busy.


Next it’s time to combine the beans and koji’d grain. The many styles of miso can vary according to the ratio of each, as well as the salt levels but my usual aim is eyeballing a 60% bean and 40% koji ratio when preparing the ingredients. Whatever I come out with in the end is what I mix together in the biggest bowl I have. Something like a potato masher can be used but I feel like this is a job for your hands to make the beginnings of your paste. The beans will mush but obviously the grain won’t yet. You can still get the general idea of the consistency already though. Add a little water here and there to get a consistency close to paste with the understanding that things will be breaking down more over time.

Then mix in salt. I hold true here to the salt to taste perspective. Salt, mix, taste, salt, mix, taste. You want something salty but pleasantly so. Not overwhelming, but not under salted.

Packing & Aging

Pack the miso in a jar or container pushing down to minimize air pockets. Leave ample head space for the big initial fermentation event on the horizon (the photo below shows too little headspace and the consequential overflowing). Many folks like to put a fresh sprinkling layer of salt over the final miso surface. It’s possible to pop a screw lid on top but the miso will commence fermentation and need some gas release. I like a loose-fitting lid but a cloth with rubber band or similar is good too. When the vigorous fermentation eventually ceases it’s a good idea to throw on some kind of lid. Depending on your conditions the miso could dry out. I’ll let the fermentation boil to a dripple in a bigger vessel, then transfer the miso to mason/ peanut butter jars and lid them to be taken to the basement for long term storage. I like breaking them down into many smaller jars so when one is being actively scooped from, the oxygen exposure is limited to just that jar as with all the microbial activity in there, things will begin to grow.

Consume when you’re ready to- in a few months, a year, or many years.

Shio Marinaed Carrot Jerky &/or Beef Jerky

fermentation, homesteading, mold, Vegetable Fermentation

Shio Koji

Shio koji is a slurry using koji rice, water, and salt that is left to ferment. The mixture matures with time into a sweet, salty, umami porridge that is perfect for using as a marinade as the enzymes in the koji asssist in tenderizing the ingredients. If you’re not familiar with koji, it is a fungus, usually grown on a grain with certain enzymes that are responsible for the unique flavors in products like miso, sake, and shoyu. I like to use the shio for almost any meat, including all poultry or even different vegetables to add another dimension to my cooking.

Making shio is very easy. I combine dry koji to water at a 1:2 ratio. Add 1 tbs salt per 2 cups of mixture, or to your preference. Pop it all in a mason jar with lid fixed snug, give it a shake, and let it do its thing at room temperature.

If you’d like to get well acquainted with it, taste it every couple of days and note how it changes. After about 2 weeks you should be at a decent spot of maturity to do some marinating. However feel free to go as long as you wish.

How to Make Homemade Clay… and ferment it!

mold, wildcrafting

Making homemade clay is another great chance to interact with the natural world around us and help us get to know our surroundings even better. It doesn’t require any special equipment and even a general knowledge can produce a good quality clay for endless hours of fun. I love clay as an off-season activity, especially as the forest floor lies barren any hike can become a scouting mission. Clay also comes with the added benefit of adding another potentially fermented skill to your fermentation-arsenal, through it’s bacterial breakdown during aging.

Finding Clay

Clay is possible to find in many regions. The best places to look are areas where there is running water such as a stream, creek, or a river. Running water washes away the less dense soil particles revealing the strong water-holding layer of clay. It can be a lot of different colors such as grey, white, orange, and red, and has a slick, plastic-y appearance when wet. When it is bone dry, it’s noticeable by its cracking.

In addition to running water, construction cuttings into the earth, such as roadwork and building foundations are also great places to hunt for clay.

When you find an area that may contain usable amounts of clay, test it first by taking a handful and kneading it in your hand. Add water if necessary and test its malleability. The properties of clay will vary from location to location. If you can roll it into a coil and bend it into a ring then you have found yourself some good quality clay to work with. My favorite places with the best success have been hillsides with deep creeks cutting through them. Often the clay is easily visible just by looking at the stratification of the soil layers.


In all cases when harvesting from nature its essential to be mindful and respectful to the place were taking from. Take only what you need and be thoughtful to not influence unnecessary destruction. The great thing about making your own clay is how easily it will return to back to the earth.

Fill up your container, whether a bag or bucket. Any “debris” such as sticks and rocks and such we will filter out later, no worries if there’s stuff in it. It may be dry or wet, either way is fine. A stick, rock, trowel, or your own paws should be sufficient to dig with.


Unload your collected clay into a large container, at least twice the size of your amount of clay. Add enough water to the container to achieve a loose slurry, it should look like chocolate milk, maybe with sticks and leaves in it. Stir it up well. If there are chunks holding together, break them up with your hands. Let rest overnight to give the water a chance to really soak in.

When you return to the slurry, check to make sure all the chunks are broken up and all the clay is dissolved into the water. Give it another good stir. When the clay is fully dissolved into the slurry you are ready for straining.

Prepare your straining apparatus. We are not necessarily looking for a tight sieve, some netting will do fine. While we want to remove any stones and forest debris, we still want some variable sized particles, just not anything noticeably big. Sand and larger (relative to clay) particles known as grog actually provide strength to clay, and helps prevent cracking and warping by influencing a more even dry. I have strained through a kitchen sieve, a dehydrator tray, and a whole variety of fabric, plastic, and metal mesh. Give the clay a good stir to loosen up anything sunk to the bottom then pour over the sieve.


At this point you should have some clean clay slurry and all we have left to do is dry off the water. Depending on the amount of excess water you may be able to skim some off the top as the clay settles down. Check for clear water on the surface.

You can blow a fan indoors or place the clay outside in the sun. In either case be mindful of surface drying and stir the clay periodically as needed to keep it working uniformly. Keep an eye on it and over the course of a few days you should see it thickening up. Watch it and play with it until you have reached a good workable consistency. Consider erring on the side of “wetter” as it’s easier to remove moisture than to add it back, but both are still possible.

Aging & Fermentation

The longer that clay is aged for the more potential it has to be broken down into finer particles that can be made into finer ceramics. Aging clay in an environment where it won’t lose moisture- such as in a plastic bag or a lidded bucket, allows the slow penetration of water in the clay particles that makes them smaller in size, and thus increases the clay’s plasticity.

During the aging of clay it can also sour. This is when bacteria present in the clay continue to decompose it. Through the process, amino acids are released which bond particles to further increase its plasticity. As the bacteria works the acidity also increases which brings particles closer together and forms a colloidal gel, which creates a very strong lattice giving the clay favorable strength. A rotten or moldy clay is prized for these reasons inspiring people to add all sorts of things like beer, vinegar, and milk to their clays. A rott-y clay can be used as a “starter” to inoculate new batches. I inoculated my clay with bacillus subtilus, a bacteria used to make the fermented food natto, but is also occurs naturally in the soil. I mixed it into the slurry during the “drying” phase, right after “sieving”, to experiment with this breaking down. And how’d it go? Who knows, but it’s about a year later and regardless the clay feels great!

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