ETHANOL PRODUCER'S DATA BASE

• "Triple scale" Hydrometer: For checking Sugar content of the mash and its alcohol potential
• Calculate % Alcohol content of the fermentation process
• Alcohol Hydrometer ( Alcoholometer ) To check the Ethanol "Proof"
• Alcohol Proof
• Proper method for accurate Hydrometer Readings
• Hydrometer Scales that can used in Ethanol making
• Hydrometer temperature correction factors 
• Refractometer: Alternate method for reading sugar content

The triple scale hydrometer is used to check for sugar content of the beer, as well as to define   the potential alcohol content of the fermented beer, as well as to check the finished beer alcohol content, based on a simple formula. See: Calculate Alcohol content of fermentation.

A hydrometer is an instrument whose function is based on

Archimedes principle. 

This principle states that a body (the hydrometer) immersed

in a fluid is buoyed up by a force equal to the weight of the displaced fluid. 

The hydrometer measures the weight of the liquid displaced by the volume of the hydrometer.

Specific Gravity is a dimensionless unit defined as the ratio of density of the material to the density of water. 

                         Water =1 g/cm³

                 Specific Gravity = Density g/cm³ 

                                                1 g/cm³

The greater the density, the tighter or closer the molecules are packed inside the substance.

Therefore, the greater the density / specific gravity of a liquid the higher a hydrometer will be buoyed by it.

Sugar Adds waight to water therefore the numbers will be POSITIVE with respect to water 

• To determine the amount of alcohol in the beer:
  • Compare the specific gravity of the beer before it starts fermenting
  • To its specific gravity when it is finished fermenting.
•  The specific gravity is a measure of the density of a liquid relative to water.
• The density of water is 1 kilogram per liter,
• So if the specific gravity of a liquid is 1.06, one liter of that liquid will weigh 1.06 kg
  • The liquid that will form the beer is called a wort (pronounced wert).
  • Its specific gravity is always higher than water because it contains a lot of dissolved sugars.
  • Yeast added to the wort will convert some of these dissolved sugars into ethyl alcohol.
  • When the beer is finished, the specific gravity is always less than when it started, because some of the sugars have been converted into alcohol, which is less dense than water (0.79 kg/L).
•  Glucose, C6H12O6 is the main sugar that will be converted to alcohol.
• Many reactions take place inside the yeast that ultimately convert:
  • Each glucose molecule into two molecules of ethyl alcohol: CH3CH2OH
  • And two molecules of carbon dioxide: CO².
    • This is the reason why we get as much CO² as we get Ethanol 
      •  
        • C6H12O6 => 2(CH3CH2OH) + 2(CO2)

 If you check the periodic table, you can figure out the molecular weights of these two molecules.

• The molecular weight of ethyl alcohol is 46.0688
• And the molecular weight of carbon dioxide is 44.0098.
  • You will need these numbers to calculate the alcohol content of the beer.

During the fermentation process most of the carbon dioxide that forms from the reaction bubbles out of the solution and leaves the fermentation vessel by way of a vent.

You can say that all of it leaves, because the amount the remains in the beer is very small compared to the amount that leaves.

If you look at the equation for the reaction you see that each glucose is split into two ethyl alcohol molecules and two carbon dioxide molecules.

That means for each carbon dioxide molecule that leaves the fermentation vessel, one ethyl alcohol molecule must be formed inside the vessel.

• If you look back at the molecular weights you can say that for each:
  • 44.0098 grams of CO2 that leaves the vessel
  • 46.0688 grams of Ethyl alcohol are formed.
  • Put another way, for each gram of CO2 that bubbles off...
  • 1.05 grams of ethyl alcohol are produced 

• To calculate an approximate alcohol by volume of your finished Ethanol
  • Take the Original gravity
  • Less the Final Gravity
  • Multiply by129 
• For example, a Mash with an original gravity of 1.050
• And a final gravity of 1.015 would be calculated as follows:
  •  1.050 -1.015 = 0.035 X 129 = 4.51%  ABV

• Take your Original Gravity reading at the very start of fermentation.
• Final Gravity reading is taken just before distilling.
• A Mash with an Original Gravity of 1.060 will end with a Final Gravity of:1.015-1.020.
• Water has a specific gravity of 1.000 
• Most hydrometers are calibrated at 60F, so you may have to adjust the gravity readings      by using the table below.
• "Hydrometer Temperature Correction factors"

• Tralles' hydrometer scale
  • A hydrometer scale calibrated so that readings are the percentage of ethanol (ethyl alcohol) by volume. 
  • Zero on the scale is the level to which the instrument sinks in pure water at 60°F,
  • 100 is the level to which it sinks in pure ethanol at 60°F.
    • It was used in Germany and in the U. S. Customs Service.

• Fill your hydrometer jar about ¾ with the liquid /alcohol you wish to test. 
• Insert the hydrometer slowly. 
• Spin gently with your thumb and index finger, to release bubbles if any have formed.
• Allow hydrometer to rest.
• Find the plane of the liquid surface.
• Eye horizontal to this plane. 
• Read at the plane cutting the hydrometer scale.
• Courtesy of: