The Easiest Way To Make Ama-koji (Sweet Rice Malt) and Amazake
Who would have thought that you could make such profound sweetness with just water and rice malt! You can still make it properly without keeping it at a constant 140F/60C. Both ama-koji (sweet rice malt( and amazake (sweet non-alcoholic rice malt beverage) make you beautiful!
Make sure to break up the rice malt if it's a solid. I usually break it up with my hands as-is without opening the package.
Turn the rice cooker onto the warming setting, and add in the rice malt. If you use refrigerated rice malt or if the pot is cold, the temperature will drop immediately, so warm it up first.
Add 150F/70C water, and mix well. It will immediately drop to 120F/50C, so close the lid and let it warm up for a bit, until it reaches above 60c.
Making sure the temperature doesn't drop too much, stir it little by little while checking the temperature. It will take about 3-4 hours for the rice malt to sweeten.
It depends on the rice cooker, but all I do is turn on the warm switch twice. Once it drops below 120F/50C, I heat it up for another 20-30 minutes and then turn it off again.
Rice malt ferments at about 130°F (110-140°F) / 55°C(45-60°C). Keep turning the warming switch on and off to prevent cooling down.
It will stop fermenting once it reaches above 160F/70C. It gets pretty hot even with the warm function, so don't cover it with a lid for too long.
If it's a rice cooker where you can set the temperature, it might be suitable to choose the lowest heat setting. Or use a yogurt maker, which sets at 130F/55C.
If you are making it in a thermos, use a 500 ml bottle. Pour hot water to warm it up before pouring the mixture in and make sure the heat doesn't drop when you change the water.
Just like in Step 3, heat to 140F/60C, and mix well. Transfer to a bottle, let sit for about 8-12 hours, and you are done!
If the temperature drops too far, then it won't be very sweet. But don't give up! If you transfer it to a pot and warm it over low heat, it'll become sweet again in a blink of an eye .
Once it's done, dilute with water to make amazake (sweet sake). You can use it just like jam or yogurt, or use it to make healthy sweets .
Freeze it in silicone cups or in ziplock bags, and make frozen treats . The dense rice malt will not freeze solid, so it's convenient!
Mix with fruit, yogurt, or tofu, or make sherbet or ice cream. Add soy milk or regular milk and make a shake. It's delicious enough without adding any sugar.
Story Behind this Recipe
Keeping the temperature constant is a pain. The temperature setting of the warming function is high, and I get the feeling that it is not so economical to leave the lid of the rice cooker open... My grandma used to make sweet rice sake by putting it in the bath. If you do it that way, the temperature will not be so high, so you could put it in a thermos and leave it overnight .
Instead of using glutinous rice or rice porridge, you can make this with just rice malt. I usually keep it heated a little over 120F/50C. It was fine even when I was careless and let the temperature rise over 150F/65C. It tastes best when used fresh, so use it as soon as possible if you keep it in the fridge. I make sure to consume it within 7-10 days.