Characterization of dissolved organic matter extracted from fermentation effluent of swine manure slurry using spectroscopic techniques and parallel factor analysis (PARAFAC)

► Humic- and protein-like fluorophores were observed in the DOM of fermentation effluent. ► The structure and component of DOM can be detected using spectroscopic techniques. ► Four fluorescent components were identified by PARAFAC model. ► The C/N ratio of DOM in fermentation process has a significant decrease.