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ON HEAD RETENTION
Author(s) -
Klopper Drs. W. J.
Publication year - 1954
Publication title -
journal of the institute of brewing
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.523
H-Index - 51
eISSN - 2050-0416
pISSN - 0046-9750
DOI - 10.1002/j.2050-0416.1954.tb06227.x
Subject(s) - hop (telecommunications) , dilution , chemistry , composite material , residue (chemistry) , materials science , chromatography , organic chemistry , thermodynamics , computer science , computer network , physics
The Σ‐test for foam stability may give misleading results, and it is inadmissible to determine this value after dilution; moreover, the foam residue towards the end of degradation has enhanced stability. In a described method for determining “foam time,” beer is foamed under standard conditions and the time is found for 95% of the beer to return from the foam. This measurement, however, does not sufficiently characterize the foam properties of a beer, and it is proposed also to measure “foam adhesion,” obtained from the position of the highest persistent foam ring on the wall of the experimental cylinder. Foam time depends on high‐molecular protein degradation products and on the hop rate, whilst foam adhesion depends almost entirely on the hop rate and, more specifically, on humulone transformation products, roaming properties are not significantly affected by esters, higher alcohols or barley fat, in the quantities likely to occur in beer.