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 micro brewing 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 describio un medidor barato para la medicion continua gravedad especifica en una operacion de microcerveceria. El aparato se basa en la medicion del cambio en la fuerza que actua sabre cuerpo inmerso en el mosto en fermentation. Las pruebas realizaron en Picaroon Brewing Co. (Fredericton,NB, Canada), en una corrida de produccion de Picaroons Red Ale. La senal de esta aparato demostro correlacionar con la gravedad especifica del liquido. Se observo una respuesta linear entre la senal del medidor y el estimado de gravedad especifica obtenida utilizando un hidrometro. Apesar de que senecesito de algunos ajustesa los datos, no se requirio de demoras significativas en el tiempo de respuesta.