Distilled Spirits - Frequently Used Proofing Processes
Distilled spirits plant proprietors are required to determine taxes owed on spirits removed from their bonded premises. To do this, proprietors will need to "gauge" the spirits, that is, determine the quantity and proof of the spirits.
If you are a distilled spirits plant proprietor, it is important that you know how to proof your spirits correctly. Below you'll find some resources to help guide you through the proofing process.
TTB Proofing Resources
- The Gauging Manual: Includes procedures and instructions for proofing distilled spirits.
- TTB Proofing Video Series (below): Detailed walkthroughs for frequently used proofing methods.
- Interpolation of Proof from Table 1 of the Gauging Manual
TTB Proofing Video Series
Whether you are new to the distilled spirits industry, or want to refine your process, these short, instructional videos will guide you, step-by-step, through several frequently used proofing procedures. The videos include close-ups of techniques and processes, and explain why it is important to correctly follow all of the steps involved in proofing spirits.
To determine which video(s) best apply to you and the proofing process you plan to use, please watch the introductory video. We recommend you watch the videos in order.
If you find these videos helpful, or if you have any suggestions on how to make this information more useful, we want to know about it! Please let us know about your questions, comments or ideas by emailing the Submit Inquiry.
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Introduction to Proofing Video Series (4:09)TTB's Beverage Alcohol Laboratory offers a proofing video series to walk you through several frequently used procedures to proof distilled spirits correctly. WMV (windows) MP4 (macintosh) |
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Part 1 - Proofing Spirits with a Hydrometer (4:29)Learn how to proof spirits using a hydrometer; this technique is cost effective and accurate. WMV (windows) MP4 (macintosh) |
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Part 2 - Proofing Spirits with a Densitometer (3:19)Learn how to proof spirits using a densitometer; this technique is fast and can be automated. WMV (windows) MP4 (macintosh) |
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Part 3 - Distilling Spirits for Proofing (4:54)High solid spirits must be distilled before proofing. Learn how to distill samples using a small laboratory distillation unit. WMV (windows) MP4 (macintosh) |
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Part 4 - Determining Proof Obscuration by Evaporation (3:08)Dissolved solids may obscure the true proof of a sample. Learn how to determine proof obscuration using the evaporation method. WMV (windows) MP4 (macintosh) |
This information is being issued to help the public to understand and comply with the laws and regulations that the Alcohol and Tobacco Tax and Trade Bureau administers. It is not intended to establish any new, or change any existing, definitions, interpretations, standards, or procedures regarding those laws and regulations. |