What Koji needs to grow and how to provide for its needs

This article sets out to explain what conditions are necessary to grow Koji and how to generate these conditions. An article on the time frame of growing Koji will follow soon. 

What always irked me about instructions on how to grow Koji (and how to make miso) is that they always explained it in a step-by-step way, rather than explaining what the essential factors are in the whole undertaking. I.e. the instructions said “use hot water bottles”, “use x amount of towels on which to let the rice cool”, “set up a bowl of water in the incubation box” etc. but not what the purpose of those actions was.

So, here I will try to summarize what Koji likes, because there are many ways to generate the necessary conditions.

What Koji needs

Pretty much every instruction says that Koji needs temperatures between roughly 28°C and 36°C (and they are right, of course). If the temperature is around 40°C the fungus starts producing spores earlier, which is not wanted almost all of the time). If the temperature is even higher the fungus will die.

Koji will produce more amylases at higher temperatures, and more proteases at lower temperature. So, depending on whether you make sake or miso you can adjust. For the beginning don’t worry about it so long as you are within 28°C and 36°C.

Koji also needs a high relative humidity. In the beginning, the first 24h, 90% are desirable. It’s no catastrophe if it’s 80%, or even 70%, but it certainly works better at 90%.

Some people say that after 24h it is better to lower humidity again, so that the fungus has to burrow deep into the grain in order to find water. If the air is always very humid the fungus can just happily grow on the outside without actually growing much into the kernel. I think there’s truth to that, but I am undecided on how much this is going to affect the amount of enzymes that are produced, which is the whole point. This is an experiment waiting to happen. :)

The Substrate

Many foods can be used as a substrate for Koji. Usually people use rice, barley or soy. If I write “rice” in the following paragraphs it also applies for all other substrates.

The rice should be:
  • Not too wet
    • This is why in all instructions it is heavily recommended that the rice is steamed, after it had been soaking for 12 hours (Barley should soak for 2-4 hours.)
    • Some even recommend keeping the rice in a sieve for 2 hours prior to steaming, to get rid of as much water as possible.
      • In a pressure cooker steaming takes about 20 minutes from the point at which it reached full pressure. In a normal pot it takes about 40 minutes.
        • For steaming, a piece of cloth is very helpful to keep everything together.
      • After steaming, the rice/barley should be spread on a layer of dry cloth or just on a clean table in order to cool down and dry. A lot of moisture will steam off and some will soak into the cloth.
      • Steamed rice will seem strangely dry, don’t worry, it is supposed to be like that. When eating it, it will seem a bit gummy.
    • Why it should not be too wet: If your rice is too wet you are making it hard for Koji to grow, and easy for bacteria (mostly Bacillus) to grow. You will notice as there won’t be much, if any, mycelium visible. Instead there will be a smell of ammonia. To get the water content of your rice perfectly right, you have to steam your rice. Cooking it will not work.
  • Dehulled/polished:
    • The rice should be white, not brown rice. Same goes for barley, it should be pearled barley, if the hull is still there the fungus can’t penetrate the kernel and nothing will happen.
    • Some people do grow Koji on natural rice, but they sprout the rice first. Anyway, if you grow Koji for the first time it is strongly recommended to do so on white rice or pearled barley as they are much easier to work with.

So this is pretty much it. The substrate part is pretty clear, so now let’s talk about the many ways to provide for heat and humidity.

How to provide for it needs

There are as many solutions as there are people making Koji.

Solutions without special equipment

At the most basic, some people use hot water bottles and towels to provide warmth for their Koji, changing them when necessary. Personally that’d be a bit too much of a hassle for me as I like to sleep at night. If you go by that route, there are very helpful thermometers with probes out there that can sound an alarm once temperature goes below or above a certain threshold – this might be helpful with other devices too.

A variation on the hot water bottle theme would be to put canisters/pots with hot water in an insulated box. An insulated box could be everything from one made of carton wrapped with blankets to special thermoboxes.

I am always in favour of using solutions that don’t require (too many) extra purchases. However, if you feel positive that it is going to be a lasting hobby, why not spend a bit of money on it. Or maybe you already have one or more of the following devices:

Solutions with “special” equipment

I have heard people have good experiences with bread proofers, which makes sense because sourdough/yeast like the same temperatures as Koji. By the same token I think there are bread baking devices out there which are meant to do every step of the baking process – if they are tweaked to do just the proofing they might be a good solution too for small batches of Koji.

Another device that seems perfect is an incubation box for chicken eggs. Somebody in one of the miso groups on Facebook talked about it, and it struck me as quite genius, since these boxes (well, the better ones I suppose) not only regulate temperature but also humidity. They can be cheap too – starting from 50€ and you are good to go.

I am sure there are plenty other options out there as well. Stuff that is used for terrariums or aquariums may be very helpful. Heating blankets may be an option too. One person I know makes perfect Koji just with a heating blanket. Ceramic heaters can be used to heat the air in a box. I have used a hair dryer for that purpose too, and it worked quite well! (It just was a bit loud every now and then)

Obviously, for some of these heat sources you will need a temperature regulating device. I use an Inkbird ITC-1000, which works quite well. It comes with a temperature probe, which I usually put directly into the rice. This is better than just regulating the temperature in the box, as the Koji will produce its own heat after some time. For this reason, after the first day, usually no heating is required anymore!

Be creative with your solutions, but make sure to stay safe. My first Koji box was made with floor heating wire, and I think it was not a safe option as the insulation of the wire once melted. Making Koji is fun, burning down your home is not!

Providing humidity

A simple way to provide humidity is to just spray the insides with water every now and then. You can also spray the cloth you are growing the Koji in (as in the photo below, in the tray section).  Probably much better to try this before spending money on a solution that works maybe marginally better than another.

Many people just put a baking tray with water over their heating element. Usually humidity will go up to 70% with that method – which is OK. It helps to put hot water in the tray in the beginning to raise humidity beyond that.

The super fancy solution, however, would be to use a humidifier. These devices are made specifically for humidifying air – perfect. Ultrasonic humidifiers work best. There are devices out there that will switch the humidifier on or off depending on relative humidity – usually they have a temperature controlling option too. The WH8040 is said to be good – it just regulates humidity, however.

I’m sure there are other solutions for humidity out there as well. If you have access to a professional kitchen you might hit the jackpot and there might be an oven that is able to regulate temperature and humidity at levels required for making Koji.

Cory Hughart commented on this article that there is another really easy way to regulate humidity. If you are using an unperforated stainless steel tray (preferably a deep one) as they are common in commercial kitchens, you can put your Koji in the tray and cover it with plastic wrap. Put some holes into the wrap so that your Koji still gets some oxygen. I would also advise to still use a piece of cloth between the tray and your Koji, so that no water is going to pool in the bottom of your tray. More on that in the next section.

Trays for Koji

One thing that really changed the quality of my Koji was the switch from a baking tray to one made of wood. The baking tray obviously didn’t soak up excess water, so the lower layer of rice sometimes got a bit soggy – not good.

I strongly recommend to incubate Koji in a wooden tray. Not only because of sogginess issues, but also because the wood will help regulate the humidity in your box. However, if you don’t have a wooden tray and it’s not easy for you to make one, you can still get some cloth and put two layers of thin cloth or one layer of thick cloth on the bottom of your baking tray or pyrex dish.

(edit March 2019: In the meanwhile, I tried perforated stainless steel trays in conjunction with thick cloth, and it worked quite well too – the key here is to avoid any pooling of water/moisture)

The tray I use

Traditionally in Japan, cedar wood is used for trays and Koji boxes (the boxes, sometimes even rooms, are called “Muro” there). Here in Austria, cedar is hard to get and expensive. In my opinion it’s probably best to use woods that are used in building saunas. So the obvious choice is spruce. It’s cheap and widely available.

Usually trays are made without metal, just with wooden joints. I was a bit lazy with mine and used screws. I don’t see a downside, except that my tray looks less fancy than it could.

Examples of Koji boxes (aka “muros”)

My first setup

Here is was using a dehydrator with a temperature control device. This is not because I think a dehydrator is inherently better, it’s just that I already had one. I put it in a cabinet as shown below.

Doesn't look too professional, I know.
My current setup – a bit of a makeshift solution, but it was alright for the first 20 batches. Now the veneer starts to get loose and wavy.

This is basically an old re-purposed sewing cabinet. The wooden tray with the rice goes on top the wooden rails (more on that later). The pot you see on the right is filled with water and I put an immersion heater in it, it is there to heighten the relative humidity of the air.

Way on the right next to the box you see the ITC-1000, which regulates the temperature. It has a probe attached to it which I always place in the middle of the koji. So depending on the temperature of the Koji, it switches the electricity of the dehydrator and the immersion heater on or off.

It is set to heat when temps fall below 30°C, and to stop heating when they are above 30.5°C. I found it’s better to have a small range of temperature, because the temperature of the Koji will lag behind and the heating phase will result not in a rise of 0.5°C, but closer to 3 or 4°C, but that’s OK.

My current setup

I have meanwhile moved on from the old sewing cabinet as the veneer started to peel off and the thing got quite gross… I built myself a cabinet from spruce stock and spruce boards.

My current setup

You can see there are two controllers, one for temperature and one for humidity. The silver thing you see on the bottom right is an ultrasonic humidifier. On the left is the dehydrator. Meanwhile I started to use a hairdryer instead of the dehydrator, as it is small, powerful and made to resist high levels of relative humidity.

The controllers switch the devices on or off, depending on the need of the moment. The temperature probe can be put into the rice, while the probe for humidity is always at the top.

Growing the Koji

Begin by diluting the spores.

Once the rice/barley/etc. has cooled down to about 35-40°C you can spread the spores with a sieve over your grains. Mix the grains well, so that the spores are distributed well.

Line your tray with a piece of cloth and then put your grains into the tray. Keep everything at the desired temperature and humidity for 24h (you can moisten the cloth a bit by spraying some water onto it, but don’t make it too wet). I usually put the thermostat probe into the rice, to ensure that the grains have the right temperature.

After 24h I stir the rice the first time. This helps to better distribute the Koji and also to stimulate it to penetrate deeper into the kernels. If you want fancy looking mats don’t stir the rice again after this point. For better penetration of Koji into the kernels it is better to stir every 4 hours or so.

This Koji has not been stirred again after the first stirring at 24h.
This Koji has not been stirred again after the first stirring at 24h. Note the slight yellowish/green color. This Koji is starting to sporulate and is very much ready for use. More on that below.
This Koji has been stirred a few times after the first stirring at 24h.
This Koji has been stirred a few times after the first stirring at 24h.

When is the Koji ready to use?

The time it takes for your Koji to be ready depends on the type of grain you are fermenting, and also on the strain of Koji you are using. Red rice Koji is ready after 40 hours, in my experience. Barley Koji can take 50 hours or longer.

In any case, if you see that your Koji is producing yellowish green spots, it is starting to produce spores. I recommend stopping the fermentation immediately by cooling the grains either in your fridge or outside if it’s cold enough. Be aware that the Koji may still be producing its own heat, so spread it out. I once just put the tray  into my room to stop the fermentation and after a few hours I came back to some really green Koji.

Heavily sporulated Koji tastes quite bad. It has a strong off-taste and if you make miso with it, the miso will discolor when it gets into contact with oxygen. It does not look good. Don’t worry if there are some yellow/green spots. It only gets problematic if everything is really green.

So the best moment to stop the fermentation is just before it starts to sporulate. I understand it is not so easy to tell when that moment is. It’s best to check your Koji quite often, especially when you make the first few times. With experience you will get a good intuition of when your Koji is ready.

Thanks for reading! If you have any critique, input or questions, please let me know!

This Post Has 35 Comments

  1. Hey Viktor!
    Danke fuer deinen Beitrag, und ich als Koji-Beginnerin bräuchte vor allem einen Artikel darueber, welches Koji ich fuer welches Projekt verwenden kann.

    Ich stehe ein wenig hilflos vor den 6 angebotenen Kojis und weiss nicht, was das Richtige ist.

    Daher meine Frage oder Bitte: Schreibst du mal was darueber? Welches Koji fuer was in etwa geeignet ist? Danke – beste Gruesse aus Köln, Sylvia

    1. Hey Sylvia!

      Danke für deine Anregung! Ich wurde gestern schon mal zu dem Thema gefragt, also habe ich nun einen Artikel geschrieben in dem die Unterschiede erklärt werden. Ich hoffe er ist hilfreich für dich! :)
      Which Koji should I buy?

      Liebe Grüße,

  2. Hi Viktor!

    Thank you for the great articles. I would like to know how the koji after being grown on the rice should be stored? As well, how the spores should be stored and how long they last for.

    Do you also have the suggestions how one should try and make miso from soy, barley and chickpeas and what the actual miso would need.
    One last question, isn’t tamari the liquid coming out of the miso not soy sauce?

    Thank you in advance!


    1. Hi Shalom!

      The Koji Rice can be stored in the fridge for up to two weeks. You can also freeze it, but it will decrease its potency somewhat.

      The spores are viable for at least a year. If they are older than one year, you can just use a bit more than usual and you will still have good results. Mold spores are made by nature to persist for a long time, after all :)
      They should be stored slightly below room temperature in a dark and dry place.

      I am planning on writing an article on how to make miso soon! You can follow either my facebook or instagram account to get the update once the article is online! :)

      When speaking of Tamari, usually the liquid coming out of a miso is meant, but it can also be a type of Shoyu, which is made from soybeans only. The latter is a bit of an artifact of the commercial marketing of soy sauce in the west.

      Kind regards,

  3. Hello Victor,
    Thank you for your articles.
    I’m an Italian house miso maker and I do my job with a very primitive sysyem: a bulb lamp into the incubator connected to a thermostat.
    What I don’t understand in your article is:
    1) what a dehydrator is for?
    2) heating the water in the pot you obtain humidity for the environment, but also you obtain the necessary heat for incubating, right?
    Thank you

    1. Hi Marcello,

      the dehydrator has the same function as your lightbulb, to warm the box. The idea with the warm water was meant to heighten the humidity, but frankly I have soon stopped with this idea. I built a new box, which I am going to describe in this article in a few weeks (hopefully).

      Kind regards,

  4. Hi Victor

    Thank you for this information. Once the koji is produced, is it possible to dehydrate the rice for longer storage?

    1. Hi Ellen,

      yes that is possible! But you need to be careful with the temperature. If it is too high, you will destroy the enzymes. So it’s best to dehydrate it at 35-40°C.

      The koji rice stays good in the fridge for one week. You can also freeze it, instead of drying it.

      Kind regards,

      1. Hi Viktor!

        Regarding the temperatures harmful for koji and its useful products, I was wondering:
        Koji produces amylase and protease enzymes (A. is useful for breakdown of starches, whereas P. breaks down protein chains).
        In beer brewing, amylase from the malted grain is essential for the conversion of starches into sugars and is most active at relatively high temperatures of around 65°C (and therefor I assume doesn‘t denature until somewhere above this temperature). Is koji amylase any different from malt amylase in this regard?
        I‘m not sure at which temp protease denatures. Do you have any information on this?
        As you note, the koji spores themselves die somewhere above 40°C.
        So, do I conclude correctly, that if you are dehydrating koji exclusively for later us as a starch converter (as in sake and amazake), one could do so at higher temperatures (up to approx. 60°C)?

        Btw, thx for your really informative website!

        1. Hi Hjalti!
          Sorry for not replying earlier =)

          You are right, in beer brewing the temperatures can be quite high. However, if I remember correctly, the mash can be kept at 35°C for the protease phase (which usually done if the mash is destined for yeast propagation. Holding 35°C will result in bad foam stability due to a lack of proteins).
          So I am assuming that higher temperatures will denature the proteases. It is for that reason that I recommend a drying temperature of 35-40°C. Probably higher temperatures are possible, but just to be on the safe side it is probably better not to use too high temperatures.
          I have not yet found much about the proteases that Koji produces, so I am assuming them to be similar to the ones in malt.

          Another interesting thing is that the guys from Noma make their beef garum at 60°C. So, surely, some protein degradation must be happening.

          So, I guess you can dehydrate your Koji at 60°C as well, but I think it’s still best to do so at 35-40°C, as the stuff itself isn’t that wet after all. I think the enzymatic potential will be higher/better if you dry it at 35-40°C.

          Kind regards,

  5. Hi Victor,

    I am about to build my first ever box for koji, an this page has been incredibly helpful! I was wondering what your newest setup is like, and how it is working out for you.

    Thank you!

    1. Hi Kal,

      I am quite happy with the new box!

      However, there are two things that I am not entirely happy with:
      1: when the door gets wet, the wood expands and I can’t close it completely anymore. Not a big deal.
      2: The upper rungs are often warmer then the lower ones. This is because after 24h the Koji starts to produce its own heat, which then of course rises up. Maybe a small fan on top would solve this problem.

      Kind regards,

  6. Hello Viktor,

    I’m very new with this but I have a lot of interest to lean about it. It is posible to grow Koji if I do now have spores, I mean can I create the atmosphere to grow it. For example at the begging of the year I was trying to make vinegar but suddenly I realized that a scoby was growing in my base so I made kombucha.

    Kind regards

    1. Hi Alejandra,

      I suppose you mean to ask if you can make Koji without spores.
      You will need the spores, it is the only way to make sure that the mold that is growing is not producing any toxins. Wild molds, like Aspergillus niger for example, produce super toxic compounds. So getting the right spores is the only way to make sure that you get a safe product.

      Kind regards,

  7. Hello Viktor, very informative thanks for sharing!
    I have setup very similar to yours, just not made of wood. The issue I’m having is regulating the humidity. I have a humidity controller and a humidifier. When I start the process everything works as it should, and when I reach the desired humidity the controller stops power to the device. Problem is when the humidity lowers, the controller turns on power to the device, but the device does not actually power on. I would then have to manually turn on the humidifier every time, defeating the purpose of the controller. Does the model of humidifier you have turn on automatically when power goes on? Any suggestions? or do i just need to buy one that starts when plugged in?

    1. Hi Alexander!
      I had the same situation once. I sent back the humidifier I bought and went on to look for another one that would turn itself on when it gets electricity. I found that it works with the Medisana humidifier. I am not a huge fan of the thing, but it does work as it should now. I kept my eye open to find a humidifier with a mechanical knob.

  8. Hello Viktor, very informative thanks for sharing!
    I have setup very similar to yours, just not made of wood. The issue I’m having is regulating the humidity. I have a humidity controller and a humidifier. When I start the process everything works as it should, and when I reach the desired humidity the controller stops power to the device. Problem is when the humidity lowers again, the controller turns on power to the device, but the device does not actually run. I would then have to manually turn on the humidifier every time, defeating the purpose of the controller. Does the model of humidifier you have turn on automatically when power goes on? Any suggestions? or do i just need to buy one that starts when plugged in?

  9. Trying to grow Koji on a mix of grains meant for my chickens… I see the spores favor the cracked corn first… Its been over 50 hours and not quite ready to harvest… have you had similar results?

    1. Hi Nick!

      Is the Koji meant for the chickens or for you? :D
      Generally I find it much, much easier to grow Koji on one thing only at a time. I.e. only on rice, only on barley, etc.
      The time it takes depends on the strain. I can’t remember right now which strain it is, but one of them can go on for a long time without starting to sporulate. If you notice that bits and pieces are starting to get yellow/green spots you should stop the Koji right away as it is starting to produce spores, and you don’t want that, they bring a bad side taste.

      Kind regards,

  10. I took a class offered by the amazing Jeremy Umansky, and his solution for keeping the humidity at the right mark just blew my mind. Now, he uses a commercial dehydrator to keep the temperature constant, so how does he keep it humid? Plastic wrap! A simple stainless steel tray with plastic wrap covering and 4 holes poked. I had developed a whole temp/humidity system with an Arduino and sensors, but instead I tried his method with a humidity probe inside the tray—and what do you know, perfect 90% humidity! I kinda feel weird giving away this amazing secret, but I don’t think he would mind (I hope).

    1. Hi Cory,

      that’s a great tip, thanks a lot! The easiest solutions are often not the most obvious ones! I will definitely put this into the article.

      Kind regards,

  11. I’m a little late in responding but I’ve just discovered koji and I’m currently about 40 hours into a koji ferment of wheat and soy (to make shoyu) unfortunately the temperature spiked overnight and I woke up to a temperature of 45°C I am wondering if this will have ruined my koji. It has not sporulated yet and I stirred and cooked it to 27°C. I’m hoping that I can still use it for the moromi. Any advice?

    1. Hi Laurel,

      I think it should be fine for moromi. It’s not ideal of course :) but it should work fine. Make sure to keep a close eye on it. If it starts to get kind of yellow/green or if it starts to “dust”, get it out of your box and make a moromi with it.

  12. Thanks for the advice. At 40 hours it has a nice coating and it looks pretty ready can I pull it now and call it done? I don’t be home to monitor it so this might be a better option.

    1. Yes, it’s probably better.

  13. Hi Viktor,

    Thanks for all the information here, it’s been very helpfull!
    I’ve been growing koji on oats to make amazake. But it has sporulated so much that I cannot use it anymore. I’d like to use it to inoculate a new batch of oats. Is this possible? Can I just mix some of it in there? Or maybe dry it, blend it and then sprinkle it on top?

    1. Hi Jan!

      it is possible to do that, but I would advise not to do it. The spores that are sold here are pure, single-species spores.
      If you continue to make your own spores from previous batches, you might easily introduce species of mold that are not as benign. I think if you do it once (i.e. to take spores from a batch that was made with pure spores), in all likelihood you’ll probably be fine, but don’t take spores from a batch that you have made from harvested spores already.

  14. Hi Viktor

    Could you help me with some advice about how to build a wooden koji tray? I am building a fermentation chamber like the speed rack type in Noma’s Guide to Fermentation, and all I need now is a tray for the koji. I tried finding a perforated sheet tray, but it was not possible to get one at a reasonable price where I live.

    Any advice about how to build a woode tray would be greatly appreciated!

    1. Hi Håvard,

      best/easiest way to do it is to get a three-layer wood panel (https://www.putzer.com/bilder/produkte/gross/Dreischichtplatte_1.jpg) from a woodshop/hardware store. Here you can buy custom sizes. Then you get a board of solid wood, about 6-10 cm high. You can then cut the lengths (or have it cut for you at the store), to fit the perimeter of your panel. Then just screw the boards and the panel together.

      Kind regards,

  15. stefano novellino
    Hi Viktor i just found your site with all those great info you want to share and i am so happy !
    thanks a lot !!!
    best regards, stefano

  16. Hi Viktor,
    your site is amazing and very informative, thank you so much. I am super new to the whole koji concept but extremely into it.
    I am looking to buy spores and give koji a go. I live in Cyprus, an island that has desirable temperatures and humidity levels for koji, but I am not sure whether I should try growing it outside?
    Another thing I don’t understand is if it’s possible to multiply koji ? is there a way to make a mother koji and stop buying spores?
    Also, I checked the koji products I can buy on your website: are these ready to be spread on soya beans or meat for example or they are good for spreading them on rice/barley to grow koji?

    looking forward to hearing from you.


    1. Hi Maria,

      thanks for the kind words :)

      I think that growing koji outside is not very easy. A stable temperature at 28-30°C is really important. This may be possible by day (in the shade!), but at night it probably cools down too much. If you are certain that you will enjoy making your own Koji and Miso, it’d probably best for you to invest in a thermostat (there are readily wired ones by inkbird) and a heating blanket or some kind of bread proofer or egg incubator. Anything to keep a stable temperature.

      If you decide to still make koji outside, put your koji in a pan or pot, with a piece of cloth between the metal and the rice. Close this vessel with cling-film, to avoid any other molds to enter.

      It is possible to make your own spores, but I do not recommend it. There is the very real likelihood that in the process you are introducing a mold that produces toxins (many of which are super potent) – and there is no way to know whether or not that is the case. In a home you can’t work cleanly enough to avoid such a contamination.

      The spores are meant to be used on any substrate. I have successfully grown koji on meat, but felt a bit unsafe :)
      For beginners I recommend to grow the white koji on rice, it is the easiest. If you feel you achieved that, you can try to grow them on barley, etc.. There is an article that explains the differences between the strains.

      Kind regards,

  17. Hi Victor,

    Ich habe eine Frage, die ich im Internet nicht beantwortet bekommen habe: deckst Du den Koji mit dem Handtuch zu oder liegt das Handtuch nur unter dem Koji und oben ist offen? Vielen Dank & liebe Grüsse

    1. Hi Philipp,

      ich decke ihn meistens schon zu. Ich mache das Tuch (ein Geschirrtuch ist besser als ein Handtuch) auch etwas feucht mit einem Wasserzerstäuber. Dadurch ist dann auch eine richtig hohe Luftfeuchtigkeit gegeben. Kann man hin und wieder dann mal checken ob es eh noch nicht ausgetrocknet ist, und bei Bedarf wieder befeuchten.

      Liebe Grüße,

  18. Hello there viktor,
    Just wanted to thank you for putting together such an informative site about Koji. As you can see I’m a newbie in this whole thing but greatly interested. I’ve just placed my first order of Koji spores and looking forward to making my firs Amazake drink and may be Miso.
    charles K.

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