Removing the horse urine-like off-odor of Gastrodia elata Blume by solid-state fermentation with Schizophyllum commune

Horse urine-like off-odor of Gastrodia elata ( G. elata ) decreased consumer acceptance. We investigated the effects of solid-state fermentation with Schizophyllum commune (CGMCC 5.84) on the odor in G. elata . The horse urine-like off-odor of G. elata was removed after fermentation. The total concentration of the key off-odorants (acetoin, m -cresol, 3-ethylphenol, 2-methoxy-4-vinylphenol, decanal and p -cresol), which might contribute to the horse urine-like off-odor of G. elata ., decreased from 616.83 μg/kg to 254.09 μg/kg after fermentation. Pleasant aroma compounds, such as acetophenone, 3-octanol, 1-octen-3-ol, decanol and phenylethanol, were produced after fermentation. Volatomics combined with non-targeted metabolomics explored the potential mechanisms of removing the off-odor in G. elata . Several involved metabolic processes such as glycolysis, butyrate metabolism, phenylalanine metabolism, phenylpropane biosynthesis, linoleic acid degradation, toluene metabolism and ethylbenzene metabolism were identified. Our results suggested a practical method for controlling off-odorants in G. elata .