Screening,identification and fermentation conditions optimization of high-yielding ethyl acetate yeast
In this study,the ester-producing yeast was used as the research object,the ethyl acetate yield was determined by gas chromatography-mass spectrometry(GC-MS)technology,and the yeast strains with high ethyl acetate yield were screened.The strains were identified by morphological ob-servation and molecular biology techniques,and the fermentation conditions were optimized by single factor and response surface experiments with the ethyl acetate yield as the response value.The results showed that a high-yielding ethyl acetate yeast strain P-3 was obtained,with an ethyl acetate yield of 134.32 mg/L.Strain P-3 was identified as Pichia kudriavzevii,and the optimal fermentation conditions for ethyl acetate production were ob-tained as follows:fermentation temperature 30℃,ethanol volume fraction 18%,and fermentation time 4 d.Under these conditions,the yield of ethyl acetate reached 281.47 mg/L,which was 109.55%higher than that before optimization.