Correlating microbes to major odorous compounds in swine manure

Malodor generation from swine manure is complicated by the involvement of many bacterial species that produce an extensive array of volatile organic compounds (VOCs). A lack of understanding of the basic manure microbiology further complicates the problem. This review covers pertinent detailed information about the indigenous bacterial genera in swine manure and their potential for producing odorous volatile compounds. It addresses not only the odorous compounds in swine manure but also the relations between bacterial species and the related compounds. It appears that volatile fatty acids may be the major odorous compounds in swine manure, and two bacterial genera, Eubacterium and Clostridium, are most likely the major contributors to these odorous acids. More research is needed to identify the bacterial species within these two genera to better understand the kinetics of malodor production by the bacteria.