How To Moonshine

Fermenting &
Distilling Basics
Making Equipment
How to Make Moonshine Using Sugar How to Make Moonshine Using Grain Moonshine Recipes

Mashing Grains for Making Moonshine

Mashing is the next step in our journey towards distilling moonshine using a grain based wash. Mashing grains is nothing like mashing potatoes for dinner and thoughts of a huge pile of spuds topped with butter or sour cream should be put aside in favour of images of boilers, grain bags and mash tuns. The theory behind mashing is discussed on the Fermenting and Distilling Basics page on preparing grain based washes.

If you have read the page on preparing grain based washes you will know that mashing is essentially mixing the grain with water and raising its temperature to one that is optimal for the enzymes contained in the grains to convert the starches present into forms of sugar that can be fermented. This optimal temperature is 63-67°C (146-156°F) for Beta-Amylase, the main enzyme used in starch conversion. Although there are four rest temperatures that you may elect to heat your mash to the main one commonly used is a single rest at 63-67°C (146-156°F). One of the most important things not to overlook is that at least 20% of the grains you add to the mash must be malted or these enzymes will simply not be available at all as they are only present after the grain has germinated. All of the grains added to the mash must be cracked, rolled or otherwise broken open to expose the starch inside.

Our example Bourbon contained a large percentage of corn which needed to be gelatinized before the other grains could be added and the corn was heated for about an hour in all of the water specified in the recipe. In this example we simply need to allow the water to cool to 63-67°C (146-156°F) before adding the other grains so that the mashing process can commence. There arent all that many grains that require an additional gelatinizing step as most commonly used grains gelatinize readily at lower temperatures than corn, most of them quite conveniently at the same temperatures needed for maximum enzyme activity.

In the majority instances where no gelatinization step was required it is likely that you will be starting with cold water and this should be heated to the required temperature. Some moonshiners prefer to heat the water with the grain already added and others prefer to heat the water directly to 63-67°C (146-156°F) and then add the grains. Experiment and see which works best for you.

Once the water and grain are mixed together they must be held at the correct temperature until the starches have been converted to fermentable sugars. Stir it occasionally and do your utmost to keep the mash at the optimum temperature but take great care that it does not go more than a couple of degrees higher as this might stop enzyme activity in its tracks. In the instance of our bourbon this took just a little over 2 hours for a reasonably complete conversion. At the beginning the mash will be quite thick and even a little difficult to stir but as the mash progresses it will thin down significantly and change to a clear brown colour very similar to an unfermented beer wort. The colour will vary according to the grains used, our bourbon was brown but had a yellow tinge thanks to the high percentage of corn as an example.

You can easily check to see if there are any starches remaining by seperating a small amount of the mash, perhaps half a teaspoon, into a saucer and adding a few drops of iodine. The iodine will turn purple in the presence of starch. If no colour change occurs the starch conversion is complete and the mashing process has been performed successfully. It can also be useful to check the specific gravity of the mash with a hydrometer, you should see a reading of about 1.050.

Once the enzymes have done their job and there is no further benefit in continuing to mash the grains you shold decide whether you are going to ferment your bourbon on the grain or off the grain. To ferment on the grain means that you will leave the remaining solids (grist) from the grain with the liquid and to ferment off the grain eans that these remaining solids will be seperated from the liquid, a process referred to as lautering. Some home distillers feel that fermenting on the grain will increase the flavour of the spirit however others such as myself feel that the grist has done its job and is now nothing more than an inconvenience. As I favour the brew in the bag approach lautering is very easy to perform, just lift the bag up so that it is clear of the wort, pour some hot water through it to rinse out the last of the wort it contains and then give it a squeeze to be sure. If you performed your mash in the traditional method then it will need to be screened. Many moonshiners build screens into the bottom of their mash tuns and this works very well, failing that let the liquid settle to the bottom of the mash tun and then carefully pour the contents of your mash tun through a screen or even a clean tea towel.

At this point the mash is complete and the resulting liquid referred to as wort or more specifically sweet wort as it is unhopped unlike a beer wort. It is also quite vulnerable to infection by wild yeasts and bacteria at this point and must be protected to avoid becoming a home to these unwanted guests. Cool the Wort as quickly as possible and keep it covered. A fan can be very useful at this point.

Some home brewers and moonshiners advocate aerating the wort prior to fermentation and this deserves a particular mention because aeration at the wrong time will change the taste of home brewed beers and spirits noticably and usually not for the best. Aeration is usually performed using an air pump and air stone such as those used in aquariums. The theory behind aeration is that the wort has been depleted of oxygen during the mashing process and is sub-optimal to start yeast. Aeration should be performed when the wort is at a suitable temperature to pitch the yeast, if the wort is aerated when hot the flavour will be affected.

Once the wort has cooled to a suitable temperature for the yeast you intend to use (usually less than 30°C) it should be transferred into a sterile fermenter, the yeast pitched and the fermenter sealed.