Development of An On-Line Specific Gravity Meter for the Craft Brewing Industry

By W.A. Brown, B.A. Brown, P.B. Stapleton & D.G. Cooper

Abstract
An inexpensive meter for the continuous measurement of specific gravity in a microbrewing operation was described. The device was based on measuring the change in force acting on a body immersed in the fermentation broth. Testing was performed at the Picaroons Brewing Co. (Fredericton, NB, Canada), on a production run of Picaroons Red Ale. The signal from this device was shown to correlate with the specific gravity of the liquid. A linear response was observed between the output of the meter and the specific gravity estimate obtained using a hydrometer. Although some filtering of the data was required, no significant lag time was imposed.
Keywords: Key Words: Specific Gravity meter, craft brewery automation, fermentation control.  

Sintesis
Se describe un instrumentobarato para la medicion continua de la gravedad especifica en una operacionde micro cerveceria. El aparato se baso en la medicion del cambio de lafuerza que actua en un cuerpo inmerso en el caldo de fermentacion, las pruebasse realizaron en la cerveceria Picaroons Brewing Co. (Fredericton, NB, Canada),en una corrida de produccion de Picarrons Red Ale. Se demonstro que la se�alde este aparato se correlaciona con la gravedad especifica del liquido.Se observo una respuesta linear entre la salida del medidor y el estimadode gravedad especifica que se obtuvo con un hidrometro. A pesar de que serequirio filtrat un poco los datos, no se impuso tiempo significativo dedemora en su obtencion.