Evaluation of an Automated Procedure for Measuring Beer Foam Stability
Peer-Reviewed Paper
MBAA TQ vol. 42, no. 3, 2005, pp.
178-183 |
VIEW ARTICLEJason K. S. Hung, Candace E. Wallin, and Charles W. Bamforth. Department of
Food Science & Technology, University of California, Davis, CA 95616-8598.
Abstract
An automated foam analyzer (Lg-automatic, Frederiksvaert, Denmark) that
assesses foam according to the sigma value foam collapse method of Ross and
Clark (as featured in the American Society of Brewing Chemists [ASBC] standard
methods) has been evaluated for its performance. There is excellent agreement in
values generated by separate operators, for successive measurements on a single
beer by one operator, and for duplicate samples of a diversity of beers. There
is a reasonable correlation between the manual procedure and the automated
version. A semiquantitative procedure for assessing beer foam performance has
been developed. There was significant variation between individuals in their
judgment of foam when using this approach. However, there was a broad
correlation between the ranking of foam quality using this test and the
stability of foam measured using the Lg-automatic machine. There was no such
relationship observed for the ASBC manual procedure.
Keywords: foam, instrumental, measurement, perception
S�ntesis
Se evalu� un analizador autom�tico de espuma (Lg-autom�tic,
Frederiksvaert, Dinamarca) que eval�a la espuma de acuerdo a su valor sigma
(m�todo Ross & Clark de la ASBC). Hubo excelente acuerdo entre los valores
determinados por operadores diferentes y para mediciones sucesivas de una misma
cerveza por un solo operador, como tambi�n para valores por duplicado de una
diversidad de cervezas. La correlaci�n entre los valores manuales y
automatizados es razonable. Se desarroll� un m�todo semi-cuantitativo para
evaluar la espuma de una cerveza, pero hubo una variabilidad significativa entre
diferentes individuos al juzgar la espuma utilizando este m�todo, si bien se
tuvo una correlaci�n razonable en el ordenamiento (�ranqueo�) de la calidad
de espuma con este m�todo y la estabilidad de la espuma dada por el instrumento
Lg-automatic. No hubo correlaci�n similar para los datos del m�todo manual.
Palabras claves: espuma, instrumentos, mediciones, percepci�n
