But what is koji? The very short answer is fungus-based microbe called ‘Aspergillus oryzae’ typically grown on rice, barley or soya beans.

From my experience, making rice or barley koji is relatively easy, but making soya bean koji is a bit more tricky since the temperature range you have to keep to ferment it is narrower than the other two. So for here, I am just showing how I make rice koji in our very small kitchen without any special equipments.

Makes 1150 – 1200g koji
1000g rice
5g koji spore powder (tane koji), but it can be more or less. Professional people apparently require only one gram for 1kg of rice.

Day One:
1. Wash rice till the water gets clear
2. Soak the rice in a bowl for over night. I leave it for 20 hours in winter but it can be a lot shorter in summer.

Day Two:
1. Drain the water from the bowl. I leave it for a couple of hours changing the angles of the colander to remove excess water.
2. Steam the rice wrapped with a cloth. I use a big pan and a steaming tray till the rice is just about soft enough to stick together when you twist some grains together. It usually takes 40 mins.
3. Sterilise all the equipment such as tray, spatula, thermometer, strainer etc.
3. Put the wrapped rice in a tray and turn them quickly with spatula to cool it down till it gets around 45℃.
4. Put the koji spore powder in a strainer and dust it onto the rice evenly. Mix well with a spatula but try not to crush the rice grains.
5. Gather all the rice together to make a big ball and wrap it with the steaming cloth and another layer of a tightly squeezed wet cloth over it. Most Japanese books tell you not to keep the steaming cloth and not to use another wet cloth but I have never failed in this way. From my very limited experience, I noticed that Koji requires a lot of water in the initial stage so you would be amazed how dry the external cloth gets within a few hours.
6. Keep the temperture of koji between 30 and 40℃ for next 24 hours. I use a cooler box with a little hot water bottle but you can just use a paper bag, a cardboard box or anything you can control the temperature. My mum told me my grandfather apparently used a duvet. So anything is fine. If the temperature goes beyond 40℃, do the step on the day three to cool it down till it gets the temperature range.

Day Three:
1. After around 24 hours, the temperature should go up since it generates heat as the fermentation becomes active. Once the temperature reaches 40℃, unwrap the koji and quickly cool it down using spatula. By this point you can notice the sweet chestnutty smell from koji. It is really beautiful.
2. Flatten the koji and put it back to the cooler box. Check the temperature every now and again for next 18 hours and whenever it gets over 40℃, repeat the cooling down process.

Day Four:
1. Keep the temperature over 40℃ for the final 6 hours and take it out.
2. Gently separate all the grains and cool it down in the room temperature.

The each rice gain should be covered with white fluffy coat. When you break the grain, you can see the white fungus invades even inside.

You can use the fresh koji for miso, amazake, shiokoji, or shoyu koji etc. You could keep it in fridge for a couple of weeks and if frozen it should last for a couple of months.

Enjoy!

The post How I make my own Koji in our small kitchen first appeared on Umami and You.

They may have expected something a bit complicated but making miso is not a rocket science. All you need is three ingredients, beans, salt and koji. At the same time, what they may have not expected to hear was ‘you have to wait for nearly a year to get it done’…miso wasn’t made in a day.

I usually adjust my miso to be a little less salty than mass production miso (11 – 12%). For example my formula this year was 1kg of dry soya beans, 1.3kg fresh rice koji and 250g of salt, which make 3kg of miso (8.3% salt).

Just to give you some idea, I have recorded the process this year for the day one and two.

What to do on the day one:

1. Wash the beans.
2. Soak the washed beans for over night or a few hours more. Just to make sure, break a bean and see if inside of the bean properly absorbed water.

That is all for the day one.

As for the day two, there are quite a bit more work to do:

1. Drain the water from the bowl and put the beans in a big pan.
2. Put plenty of water in the pan so that all the beans comfortably under the water.
3. Put the pan on a medium heat to bring it to boil.
4. Simmer the beans gently till the beans get properly soft, until the beans get easily broken when squeezed between the thumb and the little finger, in my case, it took 40 mins.
5. Take the beans out from the water. Do not throw the water away yet. Keep a cup of it, just in case you may need to adjust the consistency of miso.
6. Put the fresh koji and salt in a big bowl together and mix them well.
7. Put beans in a hard-wearing plastic bag, and crush them with hands, a wine bottle or even feet on the bag.
8. Once beans are reasonably cooled down*, put the koji and salt mix into the plastic bag and mix them really well.
   *please note never mix koji and the boiling hot beans as living koji fungus will die in too hot environment. Make it at least as cold as you can touch
9. Make balls of mix in size of a tennis ball.
10. Sterilise the jar first, then put the balls in the jars crush and flatten them each time. Never allow any air left between as it causes unwanted mould.
11. Put a paper on the top so that the surface does not touch the air too much and put a little bit of wasabi on a little dish on the top. A lot of people put some salt at the top to prevent mould but I do not do it personally.

I always store miso jars under the sink, relatively dark and cool place in our flat and leave it for a year. In this way, my miso have never gone too wrong but depending on where you store it, your miso may possibly attract unwanted mould on the top so it is safer to check every now and again.

If you find some mould on the top, just remove that part, then it should be fine. The wasabi usually works well to prevent it.

Hope you enjoy your miso making but if you have any questions, please leave a comment on this page.

On my next post, I will try to write how I make my own koji, again in our small home kitchen in London.

The post How I make my own miso in our small home kitchen first appeared on Umami and You.

It was at my sister in law’s kitchen 10 years ago. I was amazed about the totally different taste from the one I knew. It was not as salty as the mass-produced ones but had full of aroma and umami and tasted very rich.

I brought back 1-2 kg of her miso to London for a couple of times but came to wonder if I could make one in London?

Miso is made of very simple three ingredients, soya beans, salt and koji. The first two are relatively easy to get but how about koji?

Luckily, I found a Japanese lady in Wales, who sold her home-made koji but even more luckily I came across a packet of brown rice koji in an organic supermarket in Kentish Town by chance, rather so easily.

So after all, I successfully made my first miso in 2016, and the following year, I started to make my own koji, too.

I usually prepare 2-3 different types of miso every February since then and keep them fermented for 11-12 months.

Even though you use exactly the same ingredients in the same formula, the outcomes are slightly different every year, depending on the climate and condition, which is a little similar to wine.

On the next post, I will try to guide how I make my own miso at our very small kitchen in London so that you can see the process is actually quite easy. All you need to do is creating the right environment for microbes to get active for the next 11-12 months.

The post Me and Miso: from Japan to UK first appeared on Umami and You.