This section describes other mashing methods than the one given in the chapter on Mashing. The method described in the chapter on Mashing employs flaked maize, which is much easier to mash than undispersed forms of corn such as corn meal or corn flour. Undispersed grains require a full decoction (i.e. boil) to completely disperse their starches in the mash water, where flaked grains do not. Also discussed here, is the mashing of other cereal grains than corn.
All flaked grains can be mashed the same as flaked maize. Flaked maize was chosen as the example simply because corn is the subject matter of this text. Examples of other flaked grains that are used to make whiskey are: flaked rye; flaked wheat; flaked barley; and, flaked oats (i.e. rolled oats). Flaked oats (not popular as a whiskey grain) are called "rolled oats" and are probably never referred to as "flaked oats".
To mash cereal grains that are not flaked, they need to be boiled in order to disperse their starches in the mash water. To do this, the grain mash needs to be liquefied with some of the malt enzymes or the mash would turn to a thick porridge that would not boil but would burn on the bottom of the boiling vessel. Examples of widely used cereal grains for making whiskey are: corn meal; rye meal; wheat meal; and barley meal. The flour of the same grains can also be used, but requires mixing with cold water prior to adding to hot mash water to prevent clumping.
• a large plastic or wooden stirring spoon
• a floating dairy thermometer, graduated from 0oC to 110oC (32°F to 230°F)
• tincture of iodine
• measuring spoons
• 23L of fairly soft municipal tap water. E.g. hardness level of 4; almost no iron; 100 ppm calcium; pH 8.5.
• 7L cereal grain (e.g. cornmeal, rye meal, wheat meal)
• 11 L crushed 2-row or 6-row pale barley malt
Prepare 23L of pH 6 to 7 mash water as described in the chapter on Mashing. Turn the stove on high, cover the pot, and let the water heat up to the conversion strike temperature, 73oC (163oF). You will have to frequently stir the water thoroughly and measure the temperature as the water heats up until the strike temperature is reached.
When the water is at the strike temperature, turn off the heat, and stir in the cereal grain. The temperature should come to rest at about 66oC (151 oF) and the mash will become a thick porridge. At this point, it's only important that the mash is under 71oC (160oF). Next, stir in about 100-ml of the crushed barley malt. Cover the pot and leave it for about 20 minutes. It's helpful to stir the mash every few minutes.
At this point, the mash should be liquid and easy to stir. Turn the stove back on to high and stir continually while the heat is on to avoid scorching the grain on the bottom of the pot. It may be necessary to set the stove to a lower heat to avoid scorching if the pot doesn't have a thick aluminum plate bonded to the bottom. A mechanical stirring device is very helpful for this stage.
Continue heating and stirring until the mash comes to boil. This will take about 40 minutes with the stove set on high.
When the mash is boiling, cover the pot to the extent that it doesn't foam over, and leave to boil for about 20 or 30 minutes. If the pot is a pressure cooker, secure the lid in place as per the pressure cooker instructions. Under pressure, the mash will only require 10 or 15 minutes. There is no need to stir during the boil, as the rolling motion of the boil will rouse the mash enough to prevent scorching.
After the boil (or pressure cook), turn the heat off and allow the mash to cool, or force cool with an immersion chiller, to the conversion strike temperature, 66.5oC (152oF).
Next stir in the remainder of the 11L of crushed barley malt and the 5-ml (1-tsp) of gluco-amylase. The mash temperature should rest at about 65oC (149oF). Cover the mash pot and leave it for 90 minutes or longer to convert. It's helpful to stir the mash every 15 minutes or so during the 90-minute conversion rest. The mash can even be left for eight or ten hours (e.g. overnight) to cool to fermentation temperature (i.e. under 38oC (100oF)). An immersion chiller can be used to force cool the mash to fermentation temperature any time after the 90-minute conversion rest is complete.
After the conversion rest, the starches should be completely converted to sugars. This can be tested for by the iodine starch test described in the chapter on Mashing.
The mash is now ready for fermentation as per the chapter on Fermentation.
Millet is a cereal grain that is very commonly used in home whiskey making, and is contended by many distillers to make the best whiskey of all the grains. Millet is a very soft grain compared to the other grains discussed above, and for that reason doesn't require a full boil.
To mash millet, use millet meal and mash it by the same method described above for cereal grains, except that when the liquefied mash comes to boil, skip the 20 or 30-minute boil. The mash can then be cooled straight away to the conversion strike temperature and converted.
Another method is to bring the mash water to boil, turn the heat off, stir in the millet meal, and cool or force cool the mash to the conversion strike temperature. Then proceed as per the method for cereal grains.
Was this article helpful?