Hydrogen sulphide metabolic pathway

In the absence of organic sulphur compounds in wort, hydrogen sulphide arises from sulphate ions. The metabolism of sulphate ions by yeast is indicated in Fig. 17.24. Leakage of sulphide ions from the pathway is the origin... 

The biochemical pathways for reducing organic matter in the liquid phase are complex and not well known [13]. The transformation of undissociated acetic acid HAc to carbondioxide CO2 and methane CH4 can be regarded as the bottle neck of the metabolism [4]. Furthermore the sulphuric acid S04 is biologically transformed into hydrogen sulphide H2S. Undissociated... 

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