Control of Hydrogen Sulfide in Beer with a Copper Electrolysis System
MBAA TQ vol. 41, no. 1, 2004, pp. 50-52 |
VIEW ARTICLE
Egbert Pfisterer (1), Ian Richardson (2), and Attila Soti (3). 1. First Key Inc., 42 Wycliffe Crescent, Toronto, Ontario, M2K 1V6, Canada. 2. Beverage Machinery Services Inc., 200 Connie Crescent, Unit 7, Concord, Ontario, L4K 1M1, Canada. 3. Beverage Engineering Inc., 3280 Langstaff Road, Concord, Ontario, L4K 4Z8, Canada.
Abstract
In breweries, the preferred use of stainless steel rather than copper has occasionally led to increases in hydrogen sulfide (H(2)S) concentrations in beer since its elimination as copper sulfide (CuS) did not take place. Depending on the character of the underlying beer, this off-flavor can become quite noticeable. The advanced version of a copper electrolysis system eliminates this flavor defect. The unit consists of two electrodes in a stainless steel housing. A power supply allows adjustment of the current by changing the voltage to precipitate H(2)S as CuS according to Faraday�s Law; the specific potential difference between the anode and cathode depends on the beer flow rate and the volume of the electrode housing. The system is capable of controlling copper ionization to within 10 �g/L (parts per billion). The recommended location for the electrode housing is in-line, before filtration.
Keywords: beer off-flavor, copper electrolysis system, hydrogen sulfide
S�ntesis
La preferencia para la utilizaci�n de acero inoxidable en instalaciones cerveceras, en lugar de cobre, ocasionalmente ha resultado en aumentos de la concentraci�n de sulfuro de hidr�geno (H(2)S) en la cerveza debido a que no es eliminado como sulfuro de cobre (CuS). Este sabor anormal puede llegar a ser muy notable, dependiendo del car�cter de la cerveza base. Una versi�n avanzada de un sistema de electr�lisis de cobre elimina este defecto. La unidad consiste de dos electrodos en una montura de acero inoxidable. Una fuente de poder permite el ajuste de la corriente para precipitar H(2)S como CuS seg�n la Ley de Faraday. La diferencia en el potencial espec�fico entre el �nodo y el c�todo depende del caudal de la cerveza y el volumen de la montura de los electrodos. El sistema es capaz de controlar la ionizaci�n de cobre con una variaci�n m�xima de 10 �g/L. El lugar recomendado para la colocaci�n de la montura de los electrodos es en la l�nea antes del filtro.
Palabras claves: sabor anormal en cerveza, sistema de electr�lisis de cobre, sulfuro de hidr�geno
