The Role of Enzymes in Making Whiskey and Moonshine

Beer, wine, whiskey, and moonshine have been enjoyed for the longest time in history. Their production involves fermenting wort or wash (obtained from a starch-based base as we shall see later) to end up with alcohol. In the case of moonshine or whiskey, the alcohol is further distilled to increase its concentration. These starch-based bases are typically grains like barley, rye, corn, and wheat.

Different grains are used for producing different alcoholic drinks. Whiskey, for instance, is made from barley, corn, rye, and/or wheat while beer is produced. For these drinks, starch is usually the most basic ingredient derived from grain.

Let’s revisit the moonshine production process.

The fermentation process

Fermentation is the process where carbohydrates such as starch and sugar are converted into alcohol through enzyme action using yeast. Yeast produces the enzymes which then break down the carbohydrates into sugars for fermentation to take place. 

The fermentation process is different for wine, beer, and liquors as explained below. 

  • Wine. Fermentation is the easiest in wine. Wine is made from ripe fruit that has sugars naturally available in them and ferments naturally and easily when exposed to yeast that is available in the air.
  • Beer. Unlike wine, the base for beer fermentation is grain such as barley, corn, wheat, or rice. The fermentation process for beer is different because grains contain carbohydrate molecules and not sugar like in ripe fruit. These carbohydrates have to be first converted into sugars before being fermented into beer. In essence, brewing is the conversion of carbohydrates in the grain into sugars. This is done by preparing mash, a process that we shall look into shortly. 
  • Liquor. Liquor is made through a secondary process known as distillation after fermenting wine or brewing beer.

Forming mash

  1. Mash is made by mixing whole, cracked, or ground grain with hot water in a fermentation container. Others prefer boiling this mixture. The heat extracts the sweetness from the grain into the water after some hours to form mash or wort in the case of beer production or mash. 
  2. At this point, enzymes are added to convert the starches in the grain into sugars. The mixture is then strained into a fermentation vessel.
  3. Yeast is then added to the mixture to convert sugar into alcohol. The, now wash, will ferment into beer or the mash into alcohol which will then be distilled into whiskey over a period of a few days to several weeks. 
  4. Bubbling or frothing in the fermentation vessel is an indication that fermentation is taking place. When the bubbling stops, fermentation is complete. 
  5. The mash is then ready to be distilled to increase alcohol concentration in it. A process that is used for whiskey production. 
  6. The mash is poured into the still and brought to boil to a temperature of about 172 °F (78 °C)
  7. As alcohol continues to boil inside the boiler, it begins to evaporate while pressure builds inside the still. This pushes steam through the still column to the condenser where it is cooled into liquor and then collected in a container.

What are enzymes?

We have already seen that enzymes are used during the production of whiskey or moonshine, just before the fermentation process, to break down starch into sugar. 

The role of enzymes is to catalyze biochemical reactions. Enzymes are a special type of protein made up of thousands of amino acids chained together and shaped uniquely so that they will only catalyze specific reactions. For instance, lactase enzymes break down lactose into glucose. Enzyme action is affected by temperature, pressure, PH, and other environmental factors. This explains why during mash preparation grain is mixed with hot water or the mixture boiled. However, when exposed to these factors in their excess, enzymes get damaged and may not catalyze the reactions. This is known as enzyme denaturing. 

When enzymes are added to the mash, they expose fermentable sugars to allow the yeast to ferment the mash effectively.

Why are enzymes important in moonshine production?

As we have already seen, enzymes break down starch to fermentable sugars in mash, which is then fermented to produce alcohol. The alcohol is then distilled to produce moonshine. Simply put, without enzyme action, fermentation cannot take place. In whiskey production, malted barley is the most commonly used enzyme. Barley is the most commonly used grain owing to its high diastatic power. This means that it has a higher ability to break down starches into fermentable sugars. 

Some distillers use commercial enzymes particularly in the production of malt-less whiskeys. The advantage that commercial enzymes offer is that they have higher conversion hence yielding more alcohol from mashes that do not have barley. Another advantage of using commercial enzymes instead of malt is that smaller quantities of enzymes are used compared to the large quantities of malt for manageable storage and handling in addition to significantly reduced raw materials. Commercial enzymes are however not allowed in the production of scotch-whiskey.

What is malting and how are enzymes formed during malting?

Malting is the process of controlling the germination of grain to convert it to malt. 

  • Grains are soaked in water, dried in hot air to a moisture content of not more than 14%, and then stored for around 6 weeks. 
  • After this period, they are soaked in water to reabsorb moisture in a process known as steeping which causes them to start germinating. When they attain a 46% moisture content, they are laid out for around 4-6 days to air-dry.  
  • Afterward (before they fully germinate into plants), the grain will be dried in the kiln to stop the germination process and give them a unique flavor and color, and the roots and shoots removed before being used. The amount of starch-sugar conversion potential that remains in the grains after this entire process is known as diastatic power. 

NB: Sprouts should not be allowed to germinate into plants because this process uses up all the starch in the grain such that there will be no starch to be converted to sugar by the brewer. 

During malting, enzymes are formed in the grains. These are the enzymes that transform starches into sugars in a mash just before fermentation. Barley is commonly used for malting although other grains like sorghum, rye, wheat, oats, and millet can be malted.


Without enzymes, no alcohol will be produced. It is important to note that the germination of barley during malting should be done under controlled temperatures. Germination causes a number of chemical processes to take place within the grain including the production of alpha-amylase, alpha-glucosidase, and LD, enzymes that break down starch. 

As we have seen, heat (or hot water for that matter) is important in preparing mash. Different starches will gelatinize effectively at specific temperatures but generally, temperatures above 140 °F (60 °C) will reduce enzyme activity or denature the enzymes altogether. For instance, barley gelatinizes at temperatures between 125.6-138.2 °F (52-59 °c) and rye at temperatures between 134.6 and 158 °F (57-70 °C). This knowledge will help a distiller through the malting process depending on what he opts to use. On the other hand, some distillers opt for simpler commercial enzymes.