Making crystal malt at home is very easy and straightforward. It is a very rewarding process, and creates crystal malt that can be much more flavorful than is commercially available.
- Select a base malt.
- This could be basically anything as long as it has enough diastatic power to convert its starch to sugars.
- Rehydrate the malt.
- Soak the malt in chlorine-free water for 12-24 hours. The object is to get the moisture content to about 50%.
- Perform in-hull saccharification.
- Strain the rehydrated malt to remove excess water.
- Arrange in a baking dish so that the depth of the grain is about 2 inches (5cm). It is important that the bed is of uniform depth.
- Place a temperature probe in the middle of the grain bed, and place aluminum foil loosely over the top.
- Place the dish in the oven, and set the oven on the lowest setting, and heat until the probe reads 158F (70C).
- Regulate oven as necessary to maintain 155F-165F (68C-73C) for 90 minutes, stirring every 20-30 minutes. It is important that the temperature does not exceed this range to prevent enzyme denaturation.
- Roast the malt to desired color.
- Remove foil and set oven to 225F (107C), and roast for about 2 hours (stirring every 15 minutes) until dry. The malt should be about 20L at this point.
- If desired color is darker than 20L, raise temperature to 350F (177C) while continuing to stir every 15 minutes.
- Each time you stir, take a grain and cut in half to examine the color. When it is dark enough, remove grain from oven and let cool. The best way to do this is to have a small amount of the target malt on hand to make a direct comparison.