Koji basics
Amazake with a Yogurt Maker (Koji Only / With Rice)
Amazake is a naturally sweet, alcohol-free drink made from rice koji and warm water — no sugar added. Keep it at 58°C for 8 hours and the koji enzymes turn the rice starch into sugar. Two versions: rich koji-only, or lighter with cooked rice.
- Serves
- About 500 ml each
- Time
- About 8 hours (mostly hands-off)
Ingredients
Koji-only amazake (rich and sweet)
- Rice koji (dried or fresh; brown rice koji also works)200 g
- Water, warmed to 58–60°C300 ml
Amazake with cooked rice (lighter)
- Rice koji100 g
- Cooked rice (white or brown), warm150 g
- Water, warmed to 58–60°C250 ml
Method
- Pour boiling water over the yogurt maker container and spoon, and let them dry. Break up the koji with your hands if it is in clumps.
Koji only
- Put the koji and the 58–60°C water in the container and mix well.
With cooked rice
- Mix the warm rice with the 58–60°C water, breaking up the grains. Check the mixture is below 60°C, then stir in the koji.
Both versions
- Close the lid, set the yogurt maker to 58°C and 8 hours. Stir once halfway with a clean spoon.
- It is ready when it smells sweet and tastes clearly sweet. Blend it if you prefer a smooth texture.
- To store, heat it gently in a pan, stirring, until just before it boils. Cool, then keep it in a sterilised jar in the fridge.
Tips
- Temperature is everything. Koji enzymes turn starch into sugar best at around 55–60°C. Above 70°C they stop working; too low and it will not get sweet, and other microbes can grow.
- Never add koji to freshly cooked, hot rice. Bring the rice and water below 60°C first.
- Koji-only amazake is thick and very sweet. With rice, you use half the koji for the same amount, and it tastes lighter.
- Keeps for about a week in the fridge. Freeze it in an ice-cube tray to use a little at a time in cooking.
- To drink, dilute about 1:1 with water or soy milk. Grated ginger is a lovely addition. You can also use it in place of sugar in granola, dressings and baking.
- No yogurt maker? Use the keep-warm setting of a rice cooker with the lid open and a damp cloth over the top, keeping it at 55–60°C for about 8 hours.
Amazake is the first thing we make in Chie Ando's fermentation courses — the easiest way to see what koji does. Rice koji and warm water, held at the right temperature, become sweet on their own. In UMAMI & KOJI LAB in Tokyo, you make koji seasonings like this by hand and take them home.
