Only two known beer parameters are entered into the calculator, the others are calculated automatically.

The calculator uses formulas to replace extract and alcohol tables.

The calculations are based on the attenuation theory that Professor Carl Napoleon Balling derived in the mid-19th century. Balling considered the following basic quantities:

OE – exctract in original wort

A – alcohol content

ER – real extract

EA – apparent extract

For the fermentation process he introduced important quantities such as apparent and real attenuation, apparent and real fermentation, alcohol factors and attenuation quotient. He mathematically expressed the mass balance of wort during fermentation and experimentally verified it. From the determined values of alcohol and real extract of beer, the extract in original wort is calculated (great Balling formula):

OE = 100 * (2.0665 * A + ER) / (1.0665 * A + 100)

After testing and calculations, Balling derived 1 to 30 wt% for the extracts in original wort, individual alcohol factors and attenuation quotients.

To determine the values of extracts, he produced tables of relative densities of 17.5 °C / 17.5 °C.

In current brewing, extract values are determined from relative densities of 20 °C / 20 °C.

For this reason, new alcohol factor values of apparent attenuation were calculated based on the linear dependence of apparent attenuation on real attenuation by the linear regression method:

a = 0.389541 + 0.002377 * OE

The author Ing. Vilém Nohel was born in 1951. His career path was influenced by the fact that the construction of a new Radegast brewery began at the place of his birth and residence at the time when he was finishing his studies. He studied brewing at the Secondary School of Food Technology in Prague, Podskalská Street, and at the University of Chemistry and Technology in Prague.

After graduation he started to work for Severomoravské pivovary (Northern Moravian breweries), n. p., Přerov, at the Radegast Nošovice plant. He progressively worked his way through a position in the laboratory, and then all positions of chiefs and leaders in departments of the brewery and malt house. After that he was brewmaster for six years. He moved to Přerov within the company, where he held the position of production deputy of the company director.

In 1989 he was elected company director, and after the company was transformed into a joint stock company, he was its CEO.
For the last 27 years he has been the production and technical director of the Zubr, Litovel and Holba brewery group.