How To Proof Moonshine?

The once prohibited moonshine is today back, legal, and regulated. Well, legal here means that you must obtain the necessary permits to make moonshine otherwise you will be on the wrong side of the law. 

The main difference between moonshine and other types of alcoholic drinks is that moonshine does not go through the aging process. It is packed straight from the still which gives it high alcohol by volume (ABV). Moonshine can have as high ABV as 75% which translates to 150 proof. 

This brings us to the next point. 

What does proof mean in alcohol?

Alcohol proof is a measure of the alcohol (ethanol) content in an alcoholic drink. During the 1500s, moonshine was used by British sailors as currency. It was common for some traders to water down moonshine to increase their profit margin and avoid higher taxation by the government. Proofing was done to ensure that the moonshine being traded did not contain too much water. This was done by drenching a gunpowder pellet with the shine and then lighting it. Failing to light meant that the shine contained too much water. Moonshine had to contain 57.15% ABV to be able to light when mixed with gunpowder. This is about 100 proof. 

The measure of ethanol in moonshine: difference between ABV and proof

First and importantly, both ABV and proof represent the measure of ethanol in a liquid. To be precise, it is the number of milliliters of pure ethanol expressed as a percentage in 100 ml solution at 68 °F (20 °C). However, ABV is the global standard set by the International Organization of  Legal Metrology used to indicate the alcohol content in a drink and is mandatory to indicate this detail in any alcohol package. 

The proof measure, on the other hand, varies from country to country. For instance, in the United States, alcohol proof is twice the ABV percentage of alcohol while in the UK it is 1.75 times the ABV percentage. In France, the alcohol content is measured in Gay-Lusac (GL) degree measure is used. This is done by first taking the alcohol content using a hydrometer and then expressing it against a hundred parts of the mixture. 

What is a hydrometer and how is it used?

A hydrometer is an instrument used for measuring the density of a liquid against that of water, in other words, the gravity of a liquid. It contains a scale to give precise readings at a glance. There are two types of hydrometers:

  • Proofing hydrometer. This hydrometer, also known as a spirit hydrometer, is used for proofing spirits after distillation. It can measure up to 40 proof or 20% ABV. 
  • Brewing hydrometer. This hydrometer is used during fermentation to measure the gravity of mash before and after fermentation. It can take measurements of up to 200 proof or 100% ABV. 

To use a proofing hydrometer, a parrot /jar is filled with the liquid that is being measured. The hydrometer is then placed inside the parrot and the reading taken from the scale in the stem of the hydrometer.

Different methods of proofing moonshine

Proofing moonshine is a crucial phase in distilling. We have already seen how proofing was done in the past by soaking gunpowder with moonshine and then lighting it. If the gunpowder failed to light it meant that the moonshine contained less than 57.15% ABV. However, this method was not accurate and was soon replaced. 

1. The shake test 

The shake test was a classical proof test developed by moonshiners in the past. This was done by simply shaking the mason jar and examining the bubbles. If large bubbles that disappear almost instantly are produced, this is an indication that the moonshine has high ABV. In short, the faster the bubbles disappear the higher the ABV in your shine. The opposite is true. Smaller bubbles that take time to disappear means that the shine has a lower ABV. 

This method, however, is for experienced moonshiners. As a newbie, if you intend to master the shake test, consider using a hydrometer along with the shake test to see how close you are to predicting the proof of the moonshine you are testing.

2. The hydrometer test

The gravity (hydrometer) test replaced the gunpowder test in 1816. This new system was a scientific method and thus guaranteed accuracy in the measurement of density and gravity. 57.06 ABV was set as the standard and was officially standardized in 1952. 

The hydrometer measures the specific gravity or density of liquids in relation to the density of water. These instruments are made of clear glass with a stem inside that is marked with a scale as well as a bulb with a heavy substance that makes the hydrometer float upright when the test is being conducted. Hydrometers are easy to use and also easily available for home distillers.  

How to use the hydrometer with a proofing parrot?

In this case, you shall need a proofing hydrometer because you shall be taking the readings of moonshine and not mash. 

What you need?

  • Proofing hydrometer 
  • Proofing parrot 
  • Moonshine 

How to take the measurement?

  1. Put your moonshine into the cooper/stainless proofing parrot 
  2. Put the hydrometer inside the proofing parrot, positioning the drip arm of the still into the proofing parrot. As the parrot fills up the hydrometer will start to float. 
  3. Once the hydrometer floats, check the reading on the scale of the hydrometer as the distillate then drips into the collection vessel from the proofing parrot. 

Why is it important to measure the proof of moonshine?

  • Knowing the proof of moonshine for both the distiller and the consumer is important. 
  • During distillation, knowing the proof of moonshine as well as monitoring the temperature of the run is important as it helps the distiller make accurate cuts. This also helps establish a recipe that will be used in making subsequent runs to ensure consistency. 
  • Proofing when diluting the final product. This is usually done twice for aged whiskeys. First, before they are put in barrels and secondly before bottling. It is a requirement by the federal law that whiskeys be below 125 proof before entering the barrel for the aging process. The second proofing is usually done by distillers to lower the strength of whiskey to a comfortably consumable level. However, not all whiskeys will be proofed after aging. 


Incidences of impurities like methanol in moonshine are not uncommon and this is hazardous as it is known to increase the risk of renal disease. Proofing, will not only indicate the ABV percentage of alcohol in moonshine but will also facilitate the process of making cuts for runs ultimately eliminating as many impurities as possible. 

The ability of a distiller to make accurate cuts on runs and have accurate detail of the moonshine they are making is and an indication of skill and experience. As the popularity of craft spirits and barrel-aged increases, the market is keen on unique spirit recipes that enhance the consumer’s overall experience.