FILTRATION
The simplest and most common method is to use STABI-silica gel
at the final beer filtration. In this case it can be added directly
into the kieselguhr dosing unit. The required rate depends on
the desired shelf life. It normally varies between 30 and 100
g/hl.
TRANSFER PROCESS
It is possible to add STABI-silica gel directly to the storage
tank as practised with other stabilizers. In this case silica
gel has to be added to the beer as an aqueous suspension when
the beer is pumped from one storage tank to another. There the
STABI-silica gel is eliminated by sedimentation.
ANTIOXIDANTS
The addition of ascorbic acid or KMS to the finished beer improves
the colloidal stability and contributes considerably to flavour
stability. One should note, however, that the effect of antioxidants
cannot compensate for an incorrect bottling technique and that,
above all, they cannot be used to compensate for an excessive
air pick-up.
PROTEOLYTIC
This combination has also proved to be very successful. It allows
a reduction of the STABI-silica gel dosing rate (to 25 to 50 g/hl).
This has a very positive effect on costs and allows at the same
time a reduction of the enzymes dosing rate (to about 1 g/hl)
which is favourable for beer taste and head retention.
PVPP, ONE WAY-USAGE, THE RECYCLING PROCESS
It is known that the adsorption effect of STABI-silica gels towards
protein-polyphenol compounds of the beer aims mainly at the protein
side. PVPP on the other hand is effective on the polyphenol side.
STABISOL, STABISOL W, OPTIMIZATION OF BRILLIANCE
Experiments with the STABISOL process during the past years have
let to a large number of observations. However, it is still not
possible to give exact advice on the use of STABISOL in an actual
case of filtration difficulties in a brewery without preliminary
tests.
