How to make Rice Koji

Rice Koji

Rice Koji is the most inportant ingredients for Miso paste. Koji is a type of fungus that helps fermentation. It is Urban Hippie’s secret. But I can show you how to make it.

  1. Rince rice with cold running water for few times. Then leave for over night.
  2. Drain water with colander and leave for a couple of hours.
  3. Steam rice until rice is soften.SteamingRice
  4. Place rice to a bowl then cool down to body temperature.
  5. Inoculate Koji culture. Mix very well with your hand.kojikinkojikin2kojikin3
  6. Put rice in a shallow tray, cover with damped cloth. Leave in a incubator for 40 hours.  Keep temperature of rice around 38℃ and high humidity. Mix few times while rice in the incubator. After 8 hours, temperature will rise themselves. So keep your eyes open for temperature that doesn’t rise higher than 43℃.kojikin4
  7. After 40 hours, take rice out from the incubator. Leave rice for a while for cooling down and dries a little.

You can keep fresh rice koji in a fridge for a couple of week otherwise freeze it. You can make own Miso paste at home with fresh Koji, even you can make home made cloudy Sake.

We sell fresh Rice Koji $18.00/kg.

21 thoughts on “How to make Rice Koji

    • Takehito MAEDA says:

      Hi there,
      We are sorry to take long time to get back to you.
      We have not done to send our products to India. But I don’t think it’s any problem.
      Just let you know we will ship it by New Zealand post that will be quite expensive. If you know what you would like to order, please let me know then I can find out how much the freight will be.


  1. Ruth says:

    Hello, do you sell koji spores? I don’t know of anyone else in NZ and I am looking to buy some to try and make miso. Thank you for posting this by the way because I was wondering how to Many thanks, Ruth.

    • Takehito MAEDA says:

      Hi Ruth,
      I am very sorry that I totally forgot to reply. We don’t sell Koji Spores. But We sell Rice Koji. You can make Miso from our Rice Koji.
      It is good to hear that you enjoyed the post.

        • Takehito MAEDA says:

          Hi there,

          Thank you for contacting us.
          Yes you can make sake with rice koji. Many people are using our rice koji to brew their own sake!!
          We sell rice koji 1kg for $18. Please email us if you would like to buy.


  2. chazza says:

    When I got up this morning my house was filled with the aroma of rice koji….

    I use an oven heating drawer for all my fermentions (hostess trolley would also do) and I take care to place a dish of water alongside the dish of koji ferment so that it provides a bit of help to the koji (itself covered with moistened kitche towel).

    • Takehito MAEDA says:

      Hi Chazza,

      The aroma of Koji…. It is quite difficult to describe. I think it is pretty similar when you cook chest nuts. It is good idea to use heating drawer!!
      Thank you for the comment!!


    • Takehito MAEDA says:

      Hi John,

      Thank you for require. Unfortunately we don’t ship Rice Koji to over sea. It is fresh Rice Koji. So it may spoil while its shipping in room temperature.
      I think you can buy dried rice koji in US??


    • Takehito MAEDA says:

      Hi Tim,

      Thank you for your interest. I have never send Rice Koji to OZ however I can try it. See what is going to happen.
      Rice koji in 1kg bag for NZ$10.
      Please let me know how many bags you after then I can find freight cost.

      I make rice koji to order so give me about a week time before sending away.


  3. Chris says:

    I am interested in making sake, so would like to buy 1kg rice koji.
    can you let me know how much to courier to Dunedin?
    I like your site :-) cheers Chris

    • Takehito MAEDA says:

      Hi there,

      Thank you contacting us. Unfortunately we don’t send our products to oversea due to high shipping cost.
      It is often more expensive than products price.
      We are happy to send it if you don’t mind for pricy shipping cost. Please email us how many bags you after then I will find shipping cost.

      Takehito MAEDA

    • Takehito MAEDA says:

      Hi Amy,

      Thank you for contacting us. Yes we do sell Rice Koji 1kg for $18 and shipping cost will be $3.70 for 1kg.
      It will take about 1 week to get ready. Please let me know when you need it.


  4. dyoung62 says:

    Hi Takehito, we used to live in Nelson (end of 2017) and love your products, particularly the brown rice miso that we cannot get here in Wanaka.
    Two questions on koji:
    1. what is used to inoculate the rice? (I cannot read the packet in the photo) and where do I buy it here in NZ
    2. Can I use brown rice for koji?
    domo arigato
    Denise Young

    • Takehito says:

      Hi Denise,

      Thank you for your comment.
      It is Koji culture(Aspergillus Oryzae). Unfortunately we don’t sell it but I have heard that Piko Wholefoods have it. Please ask to them.
      Yes you can use brown rice to make for Koji. But it is a bit tricky because rice grain coated by rice bran. So Koji culture will not penetrate in to the grain well. Basically you need to scratch rice to help the culture penetrate easily. I use my miller to take some of bran off. But I don’t think you have one. What you can do is you steam brown rice very long( I would say 1-1.5 hours that will tear the bran. Or mix with white rice. (Brown rice 1: white rice 0.2) then steam it.

      I hope it helps.

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