Study of Sulphides Production Affecting the Fermentation Process of the Lager Beer

Abstract

In the lager brewing production process, volatile sulphides such as sulphur dioxide, hydrogen sulphide, thiols and thioesters are produced by yeast metabolism during the fermentation of lager beer. Fluctuations in malt raw materials, yeast strain characteristics and fermentation process parameter adjustments can all have an impact on sulphides, and the concentration of sulphides in finished beer can have a negative impact on the sensory tasting of lager beer. This study investigated the fermentation of sulphides in lager beer under the conditions of dissolved wort oxygen, yeast recovery, fermentation temperature and pressure, and the results showed that the longer the yeast growth time, the later the fermentation of sulphur dioxide and the lower the sulphur dioxide content in the final beer by 10mg/L. The longer the yeast recovery days, the higher the fermentation of sulphur dioxide and hydrogen sulphide. The higher the content, the higher the fermentation temperature of the lager and the faster the fermentation rate, which favours a low sulphur dioxide content at the end of the main fermentation.