Measuring finished alcohol products for label value.
Of course the most critical measurement in your distillery is the final measurement for % alcohol by volume that is to match your label value. The type of beverage you are making will determine what methods you must utilize to be compliant with the TTB regulations you are subject to. Various distillation methods are available, the evaporation method may be used for certain products while some products can be measured without pre measurement preparation, and for others the official TTB approved method is distillation or other known more accurate methods such as Gas Chromatography.
Measuring finished alcohol products with no flavoring, solids, barrel aging, or oils.
Many products such as Vodka’s, Gin’s and straight Moonshine’s contain mostly alcohol and water. A Density Meter knows the density of water and this is the bench mark that is used to determine % Alcohol by volume. The density meter measures the difference between a 100% water measurement and the alcohol and water measurement and through tables can very accurately determine the percentage of alcohol in the water. If your finished product is just alcohol and water you may use a TTB approved Density Meter to determine final label value of your finished product.
Measuring finished alcohol products with flavoring, solids, barrel aging, or oils.
Alcohol products contain solids, flavoring, coloring, aging artifacts, oils or any other elements that are not alcohol or water cannot be measured directly with a hydrometer or Density Meter. These solids “Obscure” the measurement as they will give a false reading that shows the liquid is heavier or more dense thus will give a low alcohol % reading. These solids are refereed to as “Obscuration” The TTB makes the distinction that a sample is Obsured when solids exceed more than 600 milligrams per 100 milliliters and can determine how much or what percentage of alcohol