Assay and Control of Dimethyl Sulfide in Brewery Carbon Dioxide¹

1 Presented at the 47th Annual Meeting. Miami, FL, May 1980.

Abstract

Methods were developed for assaying dimethyl sulfide (DMS) concentration in fermentor gas, activated carbon from the CO₂ purifier, and purified CO₂ and were used to characterize the pattern of DMS evolution during fermentation and removal during CO₂ purification. The gas chromatographic flame photometric assay procedures are based on a method described previously. DMS evolution during fermentation generally increased to a maximum during the first day then decreased to a lower but significant value at the end of fermentation. This was also the general pattern observed for the reduction of DMS in the fermentation medium. The water scrubber of the CO₂ purification system removed an average of 72% of the DMS from the collected fermentor gas, and the carbon purifiers removed the remainder. DMS concentration on the activated carbon was monitored at three levels in the purifier during typical purification cycles. A peak with a progressively increasing DMS concentration moved through the tower in the direction of the gas flow. Reactivation effectively reduced carbon DMS concentration to negligible levels. These observations have practical implications for CO₂ purification system control and management.

• Activated carbon
• CO₂ purification
• Dimethyl sulfide
• Fermentor gas