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
Síntesis
Se evaluó un analizador automático de espuma (Lg-automátic,
Frederiksvaert, Dinamarca) que evalúa la espuma de acuerdo a su valor sigma
(método 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 también para valores por duplicado de una
diversidad de cervezas. La correlación entre los valores manuales y
automatizados es razonable. Se desarrolló un método semi-cuantitativo para
evaluar la espuma de una cerveza, pero hubo una variabilidad significativa entre
diferentes individuos al juzgar la espuma utilizando este método, si bien se
tuvo una correlación razonable en el ordenamiento (“ranqueo”) de la calidad
de espuma con este método y la estabilidad de la espuma dada por el instrumento
Lg-automatic. No hubo correlación similar para los datos del método manual.
Palabras claves: espuma, instrumentos, mediciones, percepción
