Taxes on alcohol have been part of the United States since shortly after the country’s founding. In 1791, as a means of paying off the national debt, the newly formed U.S. government passed the “Whiskey Act” imposing the first tax on a domestically produced product. Over the next few years farmers, distillers, and consumers used armed violence and intimidation to prevent the tax from being collected. Finally, in 1794, President George Washington summoned militiamen from multiple states to silence the insurgency once and for all. This armed resistance became known as the Whiskey Rebellion.
Now, as then, taxes are levied on every gallon of spirits produced and the current government takes the tax as seriously as President Washington did 200+ years ago. The U.S. Alcohol and Tobacco Tax and Trade Bureau (TTB) levies taxes on every “proof gallon” of spirits produced. A proof gallon is defined as one liquid gallon of spirits that is 50% alcohol at 60 degrees F. Since the government takes this tax so seriously it is important that distillers measure their alcohol by volume (ABV) correctly every time.
By law, alcohol producers are required to determine taxes owed on their spirits. To do this, proprietors must “gauge” their spirits to determine the quantity and proof. Measuring alcohol by volume will vary with the spirit’s temperature so it is important to adjust each measurement by temperature. To help produce accurate ABV measurements, the TTB provides a Temperature Adjustment Chart and proofing video series to guide viewers step-by-step, through various proofing procedures.
Introduction to Proofing Video Series (4:09)
Part 1 – Proofing Spirits with a Hydrometer (4:29)
Part 2 – Proofing Spirits with a Densitometer (3:19)
Part 3 – Distilling Spirits for Proofing (4:54)
Part 4 – Determining Proof Obscuration by Evaporation (3:08)