Original extract (OE)
Original Extract (OE) is the mass in grams of sugars in 100 grams of wort, prior to fermentation, as measured on the °Plato, Brix, or MISCO Dissolved Solids scale. It can be measured directly on certain refractometers and hydrometers or converted from Original Gravity.
Apparent Attenuation (AA)
Is a measure of the amount of sugar consumed by yeast during fermentation and the extent to which the yeast has been able to successfully convert fermentable sugars into ethanol and CO2. It is calculated as the drop in extract during the fermentation divided by the OE.
Current/final gravity (FG)
Current Gravity (CG) or Final Gravity (FG) is a measure of specific gravity, at 68ºF (20ºC), at the conclusion of fermentation and is directly related to Apparent Extract (AE). Specific gravity readings can signal the end of fermentation when they stop moving. FG can be measured directly on a hydrometer or calculated based on OE and AE.
Apparent Extract (AE)
is related to Final Gravity, and represents that portion of the OE present as residual sugars which were not converted to yeast biomass, ethanol, or CO2 during fermentation. It can be expressed interchangeably as °Plato, Brix, or dissolved solids and is usually determined through calculations based on OE, or specific gravity as read on a hydrometer.
Alcohol by Volume (ABV)
Is an estimate of the percentage of alcohol per volume of beer.
º Plato from Current Gravity
This value represents the Current of Final Gravity converted to º Plato units. This number will not match the value read on a refractometer during or after fermentation.