Optimization of Fermentation Condition on Furanone Production by Zygsoaccharomyces rouxii QOR6 and Its Metabolic Characteristics

To clarify the conditions and furanone production by Zygsoaccharomyces rouxii, the fermentation conditions by Z. rouxii QOR6 were optimized through single factor and orthogonal experiments. Then the types and relative contents of volatile aroma substances were determined by gas chromatography-mass spectrometry (GC-MS). The results showed that the fermentation temperature of 28 ℃, the initial pH of 4.2, the incubation speed of 180 r/min and the inoculation amount of 20×10⁷ CFU/mL were the optimal conditions, in which the yield of HDMF reached 2.90 mg/L, 1.09 times higher than that of before optimization. There were 41 volatiles components in the fermentation broth, mainly including alcohols, aldehydes, esters, aromatics and hydrocarbons. Among them, alcohols indicated the highest content, accounting for 81.13% of the total volatiles. Other metabolites with higher relative contents were phenethylacetate (3.48%), formaldehyde (0.34%), 2,6-di-tert-butylphenol (8.77%), chloromethoxymethane (0.20%) and 3-ethyl-2,5-methylpyrazine (0.70%). This study might provide technical support for the application of the Z. rouxii in food.