Analytical Session
Guy S Derdelinckx, KU Leuven, Department of Microbial and Molecular Systems (M²S), Malt and Beer Sciences (MBS) and Leuven Food Science and Nutr
Co-author(s): Mohammadreza Khalesi, Sylvie Deckers, and Kurt
Gebruers, KU Leuven, Department of Microbial and Molecular Systems (M2S), Malt and Beer Sciences (MBS), and Leuven Food Science and Nutrition, Belgium; Vladimir Ilberg, Hochschule Wei
ABSTRACT: Primary gushing of beer consists in overfoaming
of beer out of the bottle. Nowadays, the mechanism of this phenomenon is
rather well understood, and it is possible to tackle exact aspects of
the explosion. The problem is studied by considering the volumetric and
the barometric parameters of CO2, temperature, and shaking
effects and their influences on the quantity of energy transferred to
the bottle. By considering that the bottle opening at atmospheric
pressure takes place under adiabatic conditions, that a closed beer
bottle is an isochoric thermodynamic system, as well as that all the
procedures take place at low pressure, the ideal gas law can be applied.
With the theoretical calculation it could be shown why differences
exist when applying the same methods at different analytical labs on
identical malt samples. This is the case for results observed for
gushing sensitive malt samples analyzed by the modified Carlsberg method
The calculation model was tested for malt samples in order to determine
an interval of confidence regarding the analytical lab conditions and
the risks of industrial use of contaminated grains.
Guy
Derdelinckx (1954) has been teaching specialized microbial aspects of
barley, malt, and beer at KULeuven-Belgium since 2002. After obtaining
an M.S. degree in tropical and subtropical sciences (1978), he
successively obtains a master in brewing sciences degree (1979) and a
Ph.D. degree (summa cum laude, 1985) on the flavanoid issue and boiling.
After starting his professional work at the Université Catholique de
Louvain, assuming the responsibility of the assay station, he became the
scientific advisor for different Belgian breweries. He joined KULeuven
in 1994 and for eight years he used his expertise internationally. In
2005, he went back to research and, more precisely, to exact science and
focused his work, together with his research group and with the support
of industry friends, on understanding the fundamentals of the
mechanisms of beer gushing.
