Malting is a controlled germination and drying process that changes the microstructure of a grain’s cell walls, proteins and starch granules to convert it into Malt. Various grains can be “malted” but the most common, from a distilling perspective, are barley, wheat and rye.
During the process, the grain is soaked in water for two to three days, allowing it to germinate. This process releases enzymes, which convert unfermentable starch (which is insoluble in water and not available for fermentation by yeast) to fermentable sugars. The process is then stopped by placing the malt into a Kiln to reduce the moisture content and stop the germination from continuing.