Mizuame (Homemade Rice Malt Syrup)

Instructions

1. Cook the rice with 500 ml of the water in a covered pot for 20 minutes, until very soft. Add 300 ml more hot water and stir into a loose porridge.
2. Cool the porridge to 140 F (60 C), no hotter or the malt enzymes are damaged.
3. Stir the malt powder into the warm water, then mix into the porridge until even.
4. Hold at 130 to 140 F (55 to 60 C) for 6 to 8 hours, in a slow cooker on warm, an oven on its lowest setting, or a sous vide bath. Stir every 2 hours. The mixture will thin and taste sweet.
5. Strain through a cloth-lined sieve, pressing out the liquid; discard solids.
6. Pour the liquid into a wide pot and boil gently for 5 minutes. Skim the foam.
7. Simmer on low, uncovered, 40 to 60 minutes, until reduced to about 250 ml and thick enough to coat a spoon. It thickens more as it cools.
8. Pour into a clean, dry jar while hot and cool completely before covering.