# Husk Separation (Kubessa Method) Impacts the Aging Chemistry of Beer

## TL;DR

Removing husks before brewing (Kubessa method) improves beer's aging chemistry and flavor stability.

## Contribution

The Kubessa method's impact on beer aging chemistry is empirically demonstrated using advanced analytical techniques.

## Key findings

- Husk separation inhibits over 500 aging-related compounds in beer.
- Mashing of husks introduces sulfur-containing lipid compounds.
- Compositional differences provide insights into staling protection.

## Abstract

The removal of husks
before the mashing process, also known as
the Kubessa method, is an established brewing practice often positively
associated with smoothness and better flavor-stability of beer. Empirical
evidence on the effect of the Kubessa method on beer, however, has
been lacking. Similarly, our study’s comprehensive analysis
of established brewing attributes revealed that traditional methods
do not fully capture the impact of husk separation in beer brewing.
Conclusive evidence of the Kubessa method’s impact on beer
aging chemistry was obtained through ultrahigh resolution mass spectrometry
(FT-ICR-MS), revealing intricate molecular details inaccessible to
conventional analytical techniques. The compositional information
on thousands of molecules in Kubessa beer was resolved and compared
to whole malt mashing. Machine learning algorithms applied to aging
experiments identified over 500 aging-related compounds inhibited
by husk separation. Complementary Time of flight mass spectrometry
(ToF-MS) coupled with chromatography further confirmed that the mashing
of husks introduces sulfur-containing lipid compounds. These significant
differences in the beer composition provide valuable insights for
further investigation into the staling protective effect of husk-separation
(Kubessa process) during beer production, as empirically demonstrated
in this work.